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Baghani M, Fathalizade F, Khakpai F, Fazli-Tabaei S, Zarrindast MR. Additive effect of histamine and muscimol upon induction of antinociceptive and antidepressant effects in mice. Behav Pharmacol 2024; 35:55-65. [PMID: 37401392 DOI: 10.1097/fbp.0000000000000729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/05/2023]
Abstract
We investigated the effects of histamine and GABA A receptor agents on pain and depression-like behaviors and their interaction using a tail-flick test and the forced swimming test (FST) in male mice. Our data revealed that intraperitoneal administration of muscimol (0.12 and 0.25 mg/kg) increased the percentage of maximum possible effect (%MPE) and area under the curve (AUC) of %MPE, indicating an antinociceptive response. Intraperitoneal injection of bicuculline (0.5 and 1 mg/kg) decreased %MPE and AUC of %MPE, suggesting hyperalgesia. Moreover, muscimol by reducing the immobility time of the FST elicited an antidepressant-like response but bicuculline by enhancing the immobility time of the FST caused a depressant-like response. Intracerebroventricular (i.c.v.) microinjection of histamine (5 µg/mouse) enhanced %MPE and AUC of %MPE. i.c.v. infusion of histamine (2.5 and 5 µg/mouse) decreased immobility time in the FST. Co-administration of different doses of histamine along with a sub-threshold dose of muscimol potentiated antinociceptive and antidepressant-like responses produced by histamine. Cotreatment of different doses of histamine plus a noneffective dose of bicuculline reversed antinociception and antidepressant-like effects elicited by histamine. Cotreatment of histamine, muscimol, and bicuculline reversed antinociceptive and antidepressant-like behaviors induced by the drugs. The results demonstrated additive antinociceptive and antidepressant-like effects between histamine and muscimol in mice. In conclusion, our results indicated an interaction between the histaminergic and GABAergic systems in the modulation of pain and depression-like behaviors.
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Affiliation(s)
- Matin Baghani
- Department of Physiology, Faculty of Medicine, Tehran Medical Sciences, Islamic Azad University
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences
| | - Farzan Fathalizade
- Department of Physiology, Faculty of Medicine, Tehran Medical Sciences, Islamic Azad University
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences
| | - Fatemeh Khakpai
- Department of Physiology, Faculty of Medicine, Tehran Medical Sciences, Islamic Azad University
| | - Soheila Fazli-Tabaei
- Department of Physiology, Faculty of Medicine, Tehran Medical Sciences, Islamic Azad University
| | - Mohammad-Reza Zarrindast
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences
- Iranian National Center for Addiction Studies, Tehran University of Medical Sciences
- Department of Neuroendocrinology, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran
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2
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Zahner MR, Brown MC, Chandley MJ. Inactivation of the paraventricular nucleus attenuates the cardiogenic sympathetic afferent reflex in the spontaneously hypertensive rat. J Hypertens 2024; 42:70-78. [PMID: 37889604 PMCID: PMC10792548 DOI: 10.1097/hjh.0000000000003542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/29/2023]
Abstract
BACKGROUND Myocardial ischemia causes the release of bradykinin, which stimulates cardiac afferents, causing sympathetic excitation and chest pain. Glutamatergic activation of the paraventricular hypothalamic nucleus (PVN) in the spontaneously hypertensive rat (SHR) drives elevated basal sympathetic activity. Thus, we tested the hypothesis that inactivation of the PVN attenuates the elevated reflex response to epicardial bradykinin in the SHR and that ionotropic PVN glutamate receptors mediate the elevated reflex. METHODS We recorded the arterial pressure and renal sympathetic nerve activity (RSNA) response to epicardial bradykinin application in anesthetized SHR and Wistar Kyoto (WKY) rats before and after PVN microinjection of GABA A agonist muscimol or ionotropic glutamate receptor antagonist kynurenic acid. RESULTS Muscimol significantly decreased the arterial pressure response to bradykinin from 180.4 ± 5.8 to 119.5 ± 6.9 mmHg in the SHR and from 111.8 ± 7.0 to 84.2 ± 8.3 mmHg in the WKY and the RSNA response from 186.2 ± 7.1 to 142.7 ± 7.3% of baseline in the SHR and from 201.0 ± 11.5 to 160.2 ± 9.3% of baseline in the WKY. Kynurenic acid significantly decreased the arterial pressure response in the SHR from 164.5 ± 5.0 to 126.2 ± 7.7 mmHg and the RSNA response from 189.9 ± 13.7to 168.5 ± 12.7% of baseline but had no effect in the WKY. CONCLUSION These results suggest that tonic PVN activity is critical for the full manifestation of the CSAR in both the WKY and SHR. Glutamatergic PVN activity contributes to the augmented CSAR observed in the SHR.
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Affiliation(s)
- Matthew R Zahner
- Department of Health Sciences, East Tennessee State University College of Public Health
| | - Mary C Brown
- Department of Health Sciences, East Tennessee State University College of Public Health
| | - Michelle J Chandley
- Department of Biomedical Science, East Tennessee State University College of Medicine, Johnson City, Tennessee, USA
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3
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Thomas CMP, Bouton ME, Green JT. Prelimbic cortex inactivation prevents ABA renewal based on stress state. Behav Neurosci 2023; 137:373-379. [PMID: 37824233 PMCID: PMC10872701 DOI: 10.1037/bne0000570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2023]
Abstract
Our recent research suggests that the interoceptive state associated with stress can function as a contextual stimulus for operant behavior. In the present experiment, we investigated the role of the rodent prelimbic cortex (PL), a brain region that is critical in contextual control of operant behavior, in the ability of a stressed state to produce ABA renewal of an extinguished operant response. Rats were trained to perform a lever press response for a food pellet reward during daily sessions that followed exposure to a stressor that changed each day. The response was then extinguished in the absence of stress. ABA renewal of extinguished responding occurred following exposure to another stressor (different from any used during acquisition) in control rats but not in rats that received a PL-inactivating infusion (baclofen/muscimol). Results confirm that the interoceptive state of stress can play the role of a contextual stimulus and initiate renewal (relapse) of an inhibited behavior when stress has previously been associated with the behavior. In conjunction with our previous work, the present results support the hypothesis that the PL is important for contexts, both exteroceptive and interoceptive, to exert such control over operant behavior. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
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Affiliation(s)
- Callum M. P. Thomas
- Department of Psychological Science, University of Vermont
- Neuroscience Graduate Program, University of Vermont
| | - Mark E. Bouton
- Department of Psychological Science, University of Vermont
| | - John T. Green
- Department of Psychological Science, University of Vermont
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Smith SM, Garcia E, Montelongo A, Davidson CG, Bakhtiar D, Lovett SD, Maurer AP, Burke SN. Muscimol inactivation of dorsal striatum in young and aged male rats does not affect paired associates learning performance. Behav Neurosci 2023; 137:356-363. [PMID: 37326524 PMCID: PMC10721732 DOI: 10.1037/bne0000561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Improving cognitive health for older adults requires understanding the neurobiology of age-related cognitive decline and the mechanisms underlying preserved cognition in old age. During spatial learning tasks, aged humans and rodents shift navigation preferences in favor of a stimulus-response learning strategy. This has been hypothesized to result from competitive interactions of the caudate nucleus/dorsal striatum (DS) memory system with the hippocampus (HPC)-dependent spatial/allocentric memory system. In support of this hypothesis, a recent study reported that inactivation of the DS in aged rodents rescued HPC-dependent spatial learning on a T-maze (Gardner, Gold, & Korol, 2020). Currently, it is unclear whether a shift from HPC-dependent to DS-dependent behavior also contributes to age-related cognitive decline outside of spatial learning and memory. To test the hypothesis that inactivation of the DS can restore age-related cognitive function outside of spatial behavior, the present study bilaterally inactivated the DS of young (n = 8) and aged (n = 7) rats during visuospatial paired associates learning (PAL). This study found that inactivation of the DS did not alter PAL performance in young or aged rats, but did alter a positive control, DS-dependent spatial navigation task. This observation suggests that elevated DS activity does not play a role in the decline of HPC-dependent PAL performance in aged male rats. Given the persistent tendencies of aged rodents toward DS-dependent learning, it will be worthwhile to explore further the coordination dynamics between the HPC and DS that may contribute to age-related cognitive decline. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
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Affiliation(s)
- Samantha M. Smith
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL
- Graduate Program in Biomedical Sciences, Neuroscience Concentration, University of Florida
- Center for Cognitive Aging and Memory, University of Florida, Gainesville, FL
| | - Elena Garcia
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL
| | - Anna Montelongo
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL
| | - Caroline G. Davidson
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL
| | - Denna Bakhtiar
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL
| | - Sarah D. Lovett
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL
| | - Andrew P. Maurer
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL
- Center for Cognitive Aging and Memory, University of Florida, Gainesville, FL
| | - Sara N. Burke
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL
- Center for Cognitive Aging and Memory, University of Florida, Gainesville, FL
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5
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Simmons CM, Moseley SC, Ogg JD, Zhou X, Johnson M, Wu W, Clark BJ, Wilber AA. A thalamo-parietal cortex circuit is critical for place-action coordination. Hippocampus 2023; 33:1252-1266. [PMID: 37811797 PMCID: PMC10872801 DOI: 10.1002/hipo.23578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 08/28/2023] [Accepted: 09/18/2023] [Indexed: 10/10/2023]
Abstract
The anterior and lateral thalamus (ALT) contains head direction cells that signal the directional orientation of an individual within the environment. ALT has direct and indirect connections with the parietal cortex (PC), an area hypothesized to play a role in coordinating viewer-dependent and viewer-independent spatial reference frames. This coordination between reference frames would allow an individual to translate movements toward a desired location from memory. Thus, ALT-PC functional connectivity would be critical for moving toward remembered allocentric locations. This hypothesis was tested in rats with a place-action task that requires associating an appropriate action (left or right turn) with a spatial location. There are four arms, each offset by 90°, positioned around a central starting point. A trial begins in the central starting point. After exiting a pseudorandomly selected arm, the rat had to displace the correct object covering one of two (left versus right) feeding stations to receive a reward. For a pair of arms facing opposite directions, the reward was located on the left, and for the other pair, the reward was located on the right. Thus, each reward location had a different combination of allocentric location and egocentric action. Removal of an object was scored as correct or incorrect. Trials in which the rat did not displace any objects were scored as "no selection" trials. After an object was removed, the rat returned to the center starting position and the maze was reset for the next trial. To investigate the role of the ALT-PC network, muscimol inactivation infusions targeted bilateral PC, bilateral ALT, or the ALT-PC network. Muscimol sessions were counterbalanced and compared to saline sessions within the same animal. All inactivations resulted in decreased accuracy, but only bilateral PC inactivations resulted in increased non selecting, increased errors, and longer latency responses on the remaining trials. Thus, the ALT-PC circuit is critical for linking an action with a spatial location for successful navigation.
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Affiliation(s)
- Christine M Simmons
- Department of Psychology, Program of Neuroscience, Florida State University, Tallahassee, Florida, USA
| | - Shawn C Moseley
- Department of Psychology, Program of Neuroscience, Florida State University, Tallahassee, Florida, USA
| | - Jordan D Ogg
- Department of Psychology, Program of Neuroscience, Florida State University, Tallahassee, Florida, USA
| | - Xinyu Zhou
- Department of Statistics, Florida State University, Tallahassee, Florida, USA
| | - Madeline Johnson
- Department of Psychology, Program of Neuroscience, Florida State University, Tallahassee, Florida, USA
| | - Wei Wu
- Department of Statistics, Florida State University, Tallahassee, Florida, USA
| | - Benjamin J Clark
- Department of Psychology, The University of New Mexico, Albuquerque, New Mexico, USA
| | - Aaron A Wilber
- Department of Psychology, Program of Neuroscience, Florida State University, Tallahassee, Florida, USA
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6
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den Hartigh AB, Loomis WP, Anderson MJ, Frølund B, Fink SL. Muscimol inhibits plasma membrane rupture and ninjurin-1 oligomerization during pyroptosis. Commun Biol 2023; 6:1010. [PMID: 37798443 PMCID: PMC10556065 DOI: 10.1038/s42003-023-05354-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 09/13/2023] [Indexed: 10/07/2023] Open
Abstract
Pyroptosis is a cell death process that causes inflammation and contributes to numerous diseases. Pyroptosis is mediated by caspase-1 family proteases that cleave the pore-forming protein gasdermin D, causing plasma membrane rupture and release of pathogenic cellular contents. We previously identified muscimol as a small molecule that prevents plasma membrane rupture during pyroptosis via an unidentified mechanism. Here, we show that muscimol has reversible activity to prevent cellular lysis without affecting earlier pyroptotic events. Although muscimol is a well-characterized agonist for neuronal GABAA receptors, muscimol protection is not altered by GABAA receptor antagonists or recapitulated by other GABAA agonists, suggesting that muscimol acts via a novel mechanism. We find that muscimol blocks oligomerization of ninjurin-1, which is required for plasma membrane rupture downstream of gasdermin D pore formation. Our structure-activity relationship studies reveal distinct molecular determinants defining inhibition of pyroptotic lysis compared to GABAA binding. In addition, we demonstrate that muscimol reduces lethality during LPS-induced septic shock. Together, these findings demonstrate that ninjurin-1-mediated plasma membrane rupture can be pharmacologically modulated and pave the way toward identification of therapeutic strategies for pathologic conditions associated with pyroptosis.
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Affiliation(s)
- Andreas B den Hartigh
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
| | - Wendy P Loomis
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
| | - Marisa J Anderson
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
| | - Bente Frølund
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Susan L Fink
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA.
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7
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Djerdjaj A, Rieger NS, Brady BH, Carey BN, Ng AJ, Christianson JP. Social affective behaviors among female rats involve the basolateral amygdala and insular cortex. PLoS One 2023; 18:e0281794. [PMID: 37797037 PMCID: PMC10553809 DOI: 10.1371/journal.pone.0281794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 06/02/2023] [Indexed: 10/07/2023] Open
Abstract
The ability to detect, appraise, and respond to another's emotional state is essential to social affective behavior. This is mediated by a network of brain regions responsible for integrating external cues with internal states to orchestrate situationally appropriate behavioral responses. The basolateral amygdala (BLA) and the insular cortex are reciprocally connected regions involved in social cognition and prior work in male rats revealed their contributions to social affective behavior. We investigated the functional role of these regions in female rats in a social affective preference (SAP) test in which experimental rats approach stressed juvenile but avoid stressed adult conspecifics. In separate experiments, the BLA or the insula were inhibited by local infusion of muscimol (100ng/side in 0.5μL saline) or vehicle prior to SAP tests. In both regions, muscimol interfered with preference for the stressed juvenile and naive adult, indicating that these regions are necessary for appropriate social affective behavior. In male rats, SAP behavior requires insular oxytocin but there are noteworthy sex differences in the oxytocin receptor distribution in rats. Oxytocin (500nM) administered to the insula did not alter social behavior but oxytocin infusions to the BLA increased social interaction. In sum, female rats appear to use the same BLA and insula regions for social affective behavior but sex differences exist in contribution of oxytocin in the insula.
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Affiliation(s)
- Anthony Djerdjaj
- Department of Psychology & Neuroscience, Boston College, Chestnut Hill, MA, United States of America
| | - Nathaniel S. Rieger
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA, United States of America
| | - Bridget H. Brady
- Department of Psychology & Neuroscience, Boston College, Chestnut Hill, MA, United States of America
| | - Bridget N. Carey
- Department of Psychology & Neuroscience, Boston College, Chestnut Hill, MA, United States of America
| | - Alexandra J. Ng
- Department of Psychology & Neuroscience, Boston College, Chestnut Hill, MA, United States of America
| | - John P. Christianson
- Department of Psychology & Neuroscience, Boston College, Chestnut Hill, MA, United States of America
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8
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Behrens R, Dutschmann M, Trewella M, Mazzone SB, Moe AAK. Regulation of vagally-evoked respiratory responses by the lateral parabrachial nucleus in the mouse. Respir Physiol Neurobiol 2023; 316:104141. [PMID: 37597796 DOI: 10.1016/j.resp.2023.104141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 08/04/2023] [Accepted: 08/14/2023] [Indexed: 08/21/2023]
Abstract
Vagal sensory inputs to the brainstem can alter breathing through the modulation of pontomedullary respiratory circuits. In this study, we set out to investigate the localised effects of modulating lateral parabrachial nucleus (LPB) activity on vagally-evoked changes in breathing pattern. In isoflurane-anaesthetised and instrumented mice, electrical stimulation of the vagus nerve (eVNS) produced stimulation frequency-dependent changes in diaphragm electromyograph (dEMG) activity with an evoked tachypnoea and apnoea at low and high stimulation frequencies, respectively. Muscimol microinjections into the LPB significantly attenuated eVNS-evoked respiratory rate responses. Notably, muscimol injections reaching the caudal LPB, previously unrecognised for respiratory modulation, potently modulated eVNS-evoked apnoea, whilst muscimol injections reaching the intermediate LPB selectively modulated the eVNS-evoked tachypnoea. The effects of muscimol on eVNS-evoked breathing rate changes occurred without altering basal eupneic breathing. These results highlight novel roles for the LPB in regulating vagally-evoked respiratory reflexes.
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Affiliation(s)
- Robert Behrens
- Department of Anatomy and Physiology, University of Melbourne, VIC, Australia
| | - Mathias Dutschmann
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Matthew Trewella
- Department of Anatomy and Physiology, University of Melbourne, VIC, Australia
| | - Stuart B Mazzone
- Department of Anatomy and Physiology, University of Melbourne, VIC, Australia.
| | - Aung Aung Kywe Moe
- Department of Anatomy and Physiology, University of Melbourne, VIC, Australia; Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, Australia
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9
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Dushkov A, Vosáhlová Z, Tzintzarov A, Kalíková K, Křížek T, Ugrinova I. Analysis of the Ibotenic Acid, Muscimol, and Ergosterol Content of an Amanita Muscaria Hydroalcoholic Extract with an Evaluation of Its Cytotoxic Effect against a Panel of Lung Cell Lines In Vitro. Molecules 2023; 28:6824. [PMID: 37836667 PMCID: PMC10574166 DOI: 10.3390/molecules28196824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 09/20/2023] [Accepted: 09/25/2023] [Indexed: 10/15/2023] Open
Abstract
The fungus Amanita muscaria is universally recognizable for its iconic appearance; it is also widely regarded as poisonous, inedible, and even deadly. In spite of that, there have been documented cases of use of A. muscaria-containing preparations against various diseases, including cancer, to no apparent ill effect. The search for compounds that can be used to treat cancer among various plants and fungi has been intensifying in recent years. In light of this, we describe an HPLC HILIC analytical method for the evaluation of the content of the anticancer compound ergosterol (ERG) and the neuroactive alkaloids ibotenic acid (IBO) and muscimol (MUS) that contribute significantly to the unpleasant physiological syndrome associated with A. muscaria consumption. A 'homemade' A. muscaria tincture made using 80-proof rye vodka as the solvent, an A. muscaria extract made with a standardized water-ethanol solution as the solvent, and fractions obtained from the second extract via liquid-liquid extraction with nonpolar solvents were analyzed. The study also presents the results of capillary zone electrophoresis with contactless conductivity detection and UHPLC-MS/MS analyses of the IBO and MUS content of the two native A. muscaria extracts and an evaluation of the standardized extract's cytotoxic effect against a small panel of lung cell cultures in vitro. Our results show that the standardized extract has a significant cytotoxic effect and does not contain the compounds of interest in any significant quantity.
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Affiliation(s)
- Alexander Dushkov
- Institute of Molecular Biology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria (A.T.)
| | - Zuzana Vosáhlová
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, 128 00 Prague, Czech Republic (K.K.)
| | - Alexander Tzintzarov
- Institute of Molecular Biology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria (A.T.)
| | - Květa Kalíková
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University, 128 00 Prague, Czech Republic (K.K.)
| | - Tomáš Křížek
- Department of Analytical Chemistry, Faculty of Science, Charles University, 128 00 Prague, Czech Republic;
| | - Iva Ugrinova
- Institute of Molecular Biology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria (A.T.)
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10
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Waguespack HF, Maior RS, Campos-Rodriguez C, Jacobs JT, Malkova L, Forcelli PA. Quinpirole, but not muscimol, infused into the nucleus accumbens disrupts prepulse inhibition of the acoustic startle in rhesus macaques. Neuropharmacology 2023; 235:109563. [PMID: 37116610 PMCID: PMC10461600 DOI: 10.1016/j.neuropharm.2023.109563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 04/24/2023] [Accepted: 04/25/2023] [Indexed: 04/30/2023]
Abstract
Sensorimotor gating is the ability to suppress motor responses to irrelevant sensory inputs. This response is disrupted in a range of neuropsychiatric disorders. Prepulse inhibition (PPI) of the acoustic startle response (ASR) is a form of sensorimotor gating in which a low-intensity prepulse immediately precedes a startling stimulus, resulting in an attenuation of the startle response. PPI is conserved across species and the underlying circuitry mediating this effect has been widely studied in rodents. However, recent work from our laboratories has shown an unexpected divergence between the circuitry controlling PPI in rodents as compared to macaques. The nucleus accumbens, a component of the basal ganglia, has been identified as a key modulatory node for PPI in rodents. The role of the nucleus accumbens in modulating PPI in primates has yet to be investigated. We measured whole-body PPI of the ASR in six rhesus macaques following (1) pharmacological inhibition of the nucleus accumbens using the GABAA agonist muscimol, and (2) focal application of the dopamine D2/3 agonist quinpirole (at 3 doses). We found that quinpirole, but not muscimol, infused into the nucleus accumbens disrupts prepulse inhibition in monkeys. These results differ from those observed in rodents, where both muscimol and quinpirole disrupt prepulse inhibition.
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Affiliation(s)
- Hannah F Waguespack
- Interdisciplinary Program in Neuroscience, Georgetown University, USA; Department of Pharmacology & Physiology, Georgetown University, USA
| | - Rafael S Maior
- Department of Pharmacology & Physiology, Georgetown University, USA; Laboratory of Neurosciences and Behavior, Department of Physiological Sciences, Institute of Biology, University of Brasilia, Brasilia, Brazil
| | | | - Jessica T Jacobs
- Interdisciplinary Program in Neuroscience, Georgetown University, USA; Department of Pharmacology & Physiology, Georgetown University, USA
| | - Ludise Malkova
- Interdisciplinary Program in Neuroscience, Georgetown University, USA; Department of Pharmacology & Physiology, Georgetown University, USA
| | - Patrick A Forcelli
- Interdisciplinary Program in Neuroscience, Georgetown University, USA; Department of Pharmacology & Physiology, Georgetown University, USA; Department of Neuroscience, Georgetown University, Washington DC, USA.
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Bao Z, Chen X, Li Y, Jiang W, Pan D, Ma L, Wu Y, Chen Y, Chen C, Wang L, Zhao S, Wang T, Lu WY, Ma C, Wang S. The hepatic GABAergic system promotes liver macrophage M2 polarization and mediates HBV replication in mice. Antiviral Res 2023; 217:105680. [PMID: 37494980 DOI: 10.1016/j.antiviral.2023.105680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 07/17/2023] [Accepted: 07/23/2023] [Indexed: 07/28/2023]
Abstract
Macrophages display functional phenotypic plasticity. Hepatitis B virus (HBV) infection induces polarizations of liver macrophages either to M1-like pro-inflammatory phenotype or to M2-like anti-inflammatory phenotype. Gamma-aminobutyric acid (GABA) signaling exists in various non-neuronal cells including hepatocytes and some immune cells. Here we report that macrophages express functional GABAergic signaling components and activation of type A GABA receptors (GABAARs) promotes M2-polarization thus advancing HBV replication. Notably, intraperitoneal injection of GABA or the GABAAR agonist muscimol increased HBV replication in HBV-carrier mice that were generated by hydrodynamical injection of adeno-associated virus/HBV1.2 plasmids (pAAV/HBV1.2). The GABA-augmented HBV replication in HBV-carrier mice was significantly reduced by the GABAAR inhibitor picrotoxin although picrotoxin had no significant effect on serum HBsAg levels in control HBV-carrier mice. Depletion of liver macrophages by liposomal clodronate treatment also significantly reduced the GABA-augmented HBV replication. Yet adoptive transfer of liver macrophages isolated from GABA-treated donor HBV-carrier mice into the liposomal clodronate-pretreated recipient HBV-carrier mice restored HBV replication. Moreover, GABA or muscimol treatment increased the expression of "M2" cytokines in macrophages, but had no direct effect on HBV replication in the HepG2.2.15 cells, HBV1.3-transfected Huh7, HepG2, or HepaRG cells, or HBV-infected Huh7-NTCP cells. Taken together, these results suggest that increasing GABA signaling in the liver promotes HBV replication in HBV-carrier mice by suppressing the immunity of liver macrophages, but not by increasing the susceptibility of hepatocytes to HBV infection. Our study shows that a previously unknown GABAergic system in liver macrophage has an essential role in HBV replication.
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Affiliation(s)
- Ziyou Bao
- Department of Immunology, Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Provincial Key Laboratory of Infection & Immunology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Xiaotong Chen
- Medical Science and Technology Innovation Center, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, China; Department of Immunology, School of Clinical and Basic Medical Sciences, Shandong First Medical University& Shandong Academy of Medical Sciences, Jinan, China
| | - Yan Li
- Translational Medical Research Centre, The First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan Hospital, Jinan, China
| | - Wenshan Jiang
- Medical Science and Technology Innovation Center, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, China
| | - Di Pan
- Department of Immunology, Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Provincial Key Laboratory of Infection & Immunology, School of Basic Medical Science, Shandong University, Jinan, China; Department of Physiology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Lushun Ma
- Medical Science and Technology Innovation Center, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, China; Department of Paediatric Surgery, Tianjin Medical University General Hospital, Tianjin, China
| | - Yunxiao Wu
- Department of Physiology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Yunling Chen
- Department of Immunology, Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Provincial Key Laboratory of Infection & Immunology, School of Basic Medical Science, Shandong University, Jinan, China; Department of Physiology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Chaojia Chen
- Department of Immunology, Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Provincial Key Laboratory of Infection & Immunology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Liyuan Wang
- Department of Immunology, Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Provincial Key Laboratory of Infection & Immunology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Songbo Zhao
- Department of Immunology, Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Provincial Key Laboratory of Infection & Immunology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Tixiao Wang
- Department of Immunology, Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Provincial Key Laboratory of Infection & Immunology, School of Basic Medical Science, Shandong University, Jinan, China
| | - Wei-Yang Lu
- Department of Physiology and Pharmacology, Robarts Research Institute, University of Western Ontario, Canada.
| | - Chunhong Ma
- Department of Immunology, Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Provincial Key Laboratory of Infection & Immunology, School of Basic Medical Science, Shandong University, Jinan, China.
| | - Shuanglian Wang
- Medical Science and Technology Innovation Center, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, China.
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12
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Aikins AO, Farmer GE, Little JT, Cunningham JT. Effects of bile duct ligation on the inhibitory control of supraoptic vasopressin neurons. J Neuroendocrinol 2023; 35:e13312. [PMID: 37337093 PMCID: PMC10942741 DOI: 10.1111/jne.13312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 05/02/2023] [Accepted: 05/11/2023] [Indexed: 06/21/2023]
Abstract
Dilutional hyponatremia due to increased plasma arginine vasopressin (AVP) is associated with liver cirrhosis. However, plasma AVP remains elevated despite progressive hypoosmolality. This study investigated changes to inhibitory control of supraoptic nucleus (SON) AVP neurons during liver cirrhosis. Experiments were conducted with adult male Sprague-Dawley rats. Bile duct ligation was used as a model of chronic liver cirrhosis. An adeno-associated virus containing a construct with an AVP promoter and either green fluorescent protein (GFP) or a ratiometric chloride indicator, ClopHensorN, was bilaterally injected into the SON of rats. After 2 weeks, rats received either BDL or sham surgery, and liver cirrhosis was allowed to develop for 4 weeks. In vitro, loose patch recordings of action potentials were obtained from GFP-labeled and unlabeled SON neurons in response to a brief focal application of the GABAA agonist muscimol (100 μM). Changes to intracellular chloride ([Cl]i) following muscimol application were determined by changes to the fluorescence ratio of ClopHensorN. The contribution of cation chloride cotransporters NKCC1 and KCC2 to changes in intracellular chloride was investigated using their respective antagonists, bumetanide (BU, 10 μM) and VU0240551 (10 μM). Plasma osmolality and hematocrit were measured as a marker of dilutional hyponatremia. The results showed reduced or absent GABAA -mediated inhibition in a greater proportion of AVP neurons from BDL rats as compared to sham rats (100% inhibition in sham vs. 47% in BDL, p = .001). Muscimol application was associated with increased [Cl]i in most cells from BDL as compared to cells from sham rats (χ2 = 30.24, p < .001). NKCC1 contributed to the impaired inhibition observed in BDL rats (p < .001 BDL - BU vs. BDL + BU). The results show that impaired inhibition of SON AVP neurons and increased intracellular chloride contribute to the sustained dilutional hyponatremia in liver cirrhosis.
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Affiliation(s)
- Ato O Aikins
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas, USA
| | - George E Farmer
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas, USA
| | - Joel T Little
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas, USA
| | - J Thomas Cunningham
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas, USA
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13
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Duszkiewicz AJ, Rossato JI, Moreno A, Takeuchi T, Yamasaki M, Genzel L, Spooner P, Canals S, Morris RGM. Execution of new trajectories toward a stable goal without a functional hippocampus. Hippocampus 2023; 33:769-786. [PMID: 36798045 PMCID: PMC10946713 DOI: 10.1002/hipo.23497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Revised: 12/06/2022] [Accepted: 12/14/2022] [Indexed: 02/18/2023]
Abstract
The hippocampus is a critical component of a mammalian spatial navigation system, with the firing sequences of hippocampal place cells during sleep or immobility constituting a "replay" of an animal's past trajectories. A novel spatial navigation task recently revealed that such "replay" sequences of place fields can also prospectively map onto imminent new paths to a goal that occupies a stable location during each session. It was hypothesized that such "prospective replay" sequences may play a causal role in goal-directed navigation. In the present study, we query this putative causal role in finding only minimal effects of muscimol-induced inactivation of the dorsal and intermediate hippocampus on the same spatial navigation task. The concentration of muscimol used demonstrably inhibited hippocampal cell firing in vivo and caused a severe deficit in a hippocampal-dependent "episodic-like" spatial memory task in a watermaze. These findings call into question whether "prospective replay" of an imminent and direct path is actually necessary for its execution in certain navigational tasks.
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Affiliation(s)
- Adrian J. Duszkiewicz
- Centre for Discovery Brain Sciences, Edinburgh NeuroscienceUniversity of EdinburghEdinburghUK
- Department of PsychologyUniversity of StirlingStirlingScotlandUK
| | - Janine I. Rossato
- Centre for Discovery Brain Sciences, Edinburgh NeuroscienceUniversity of EdinburghEdinburghUK
- Department of PhysiologyUniversidade Federal do Rio Grande do NorteRio Grande do NorteBrazil
| | - Andrea Moreno
- Centre for Discovery Brain Sciences, Edinburgh NeuroscienceUniversity of EdinburghEdinburghUK
- Instituto de Neurociencias, CSIC‐UMHSan Juan de AlicanteSpain
- Department of Biomedicine, Danish Research Institute of Translational Neuroscience (DANDRITE)Aarhus UniversityAarhus CDenmark
| | - Tomonori Takeuchi
- Centre for Discovery Brain Sciences, Edinburgh NeuroscienceUniversity of EdinburghEdinburghUK
- Department of Biomedicine, Danish Research Institute of Translational Neuroscience (DANDRITE)Aarhus UniversityAarhus CDenmark
| | - Miwako Yamasaki
- Department of Anatomy, Graduate School of MedicineHokkaido UniversitySapporoJapan
| | - Lisa Genzel
- Centre for Discovery Brain Sciences, Edinburgh NeuroscienceUniversity of EdinburghEdinburghUK
- Donders Institute for Brain, Cognition, and BehaviourRadboud University and RadboudumcNijmegenThe Netherlands
| | - Patrick Spooner
- Centre for Discovery Brain Sciences, Edinburgh NeuroscienceUniversity of EdinburghEdinburghUK
| | - Santiago Canals
- Instituto de Neurociencias, CSIC‐UMHSan Juan de AlicanteSpain
| | - Richard G. M. Morris
- Centre for Discovery Brain Sciences, Edinburgh NeuroscienceUniversity of EdinburghEdinburghUK
- Instituto de Neurociencias, CSIC‐UMHSan Juan de AlicanteSpain
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14
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Ajaz R, Mousavi SR, Mirsattari SM, Leung LS. Paroxysmal slow-wave discharges in a model of absence seizure are coupled to gamma oscillations in the thalamocortical and limbic systems. Epilepsy Res 2023; 191:107103. [PMID: 36841021 DOI: 10.1016/j.eplepsyres.2023.107103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 01/21/2023] [Accepted: 02/09/2023] [Indexed: 02/16/2023]
Abstract
OBJECTIVE Using the gamma-butyrolactone (GBL) model of absence seizures in Long-Evans rats, this study investigated if gamma (30-160 Hz) activity were cross-frequency modulated by the 2-6 Hz slow-wave discharges induced by GBL in the limbic system. We hypothesized that inactivation of the nucleus reuniens (RE), which projects to frontal cortex (FC) and hippocampus, would affect the cross-frequency coupling of gamma (γ) in different brain regions. METHODS Local field potentials were recorded by electrodes implanted in the FC, ventrolateral thalamus (TH), basolateral amygdala (BLA), nucleus accumbens (NAC), and dorsal hippocampus (CA1) of behaving rats. At each electrode, the coupling between the γ amplitude envelope to the phase of the 2-6 Hz slow-waves (SW) was measured by modulation index (MI) or cross-frequency coherence (CFC) of γ amplitude with SW. In separate experiments, the RE was infused with saline or GABAA receptor agonist, muscimol, before the injection of GBL. RESULTS Following GBL injection, an increase in MI and CFC of SW to γ1 (30-58 Hz), γ2 (62-100 Hz) and γ3 (100-160 Hz) bands was observed at the FC, hippocampus and BLA, with significant increase in SW-γ1 and SW-γ3 coupling at TH, and increase in peak SW-γ1 CFC at NAC. Strong SW-γ modulation was also found during baseline immobility high-voltage spindles. Muscimol inactivation of RE, as compared to saline infusion, significantly decreased SW-γ1 CFC in the FC, and peak frequency of the SW-γ1 CFC in the thalamus, but did not significantly alter SW-γ CFCs in the hippocampus, BLA or NAC. SIGNIFICANCE The paroxysmal 2-6 Hz SW discharges, a hallmark of absence seizure, significantly modulate γ activity in the hippocampus, BLA and NAC, suggesting a modulation of limbic functions. RE inactivation disrupted the SW modulation of FC and TH, partly supporting our hypothesis that RE participates in the modulation of SW discharges.
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Affiliation(s)
- Rukham Ajaz
- Graduate Program in Neuroscience, University of Western Ontario, London, ON, Canada
| | - Seyed Reza Mousavi
- Clinical Neurological Sciences, University of Western Ontario, London, ON, Canada
| | - Seyed M Mirsattari
- Graduate Program in Neuroscience, University of Western Ontario, London, ON, Canada; Clinical Neurological Sciences, University of Western Ontario, London, ON, Canada
| | - L Stan Leung
- Graduate Program in Neuroscience, University of Western Ontario, London, ON, Canada; Departments of Physiology and Pharmacology, University of Western Ontario, London, ON, Canada.
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15
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Ito W, Palmer AJ, Morozov A. Social Synchronization of Conditioned Fear in Mice Requires Ventral Hippocampus Input to the Amygdala. Biol Psychiatry 2023; 93:322-330. [PMID: 36244803 PMCID: PMC10069289 DOI: 10.1016/j.biopsych.2022.07.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 06/17/2022] [Accepted: 07/11/2022] [Indexed: 01/21/2023]
Abstract
BACKGROUND Social organisms synchronize behaviors as an evolutionary-conserved means of thriving. Synchronization under threat, in particular, benefits survival and occurs across species, including humans, but the underlying mechanisms remain unknown because of the scarcity of relevant animal models. Here, we developed a rodent paradigm in which mice synchronized a classically conditioned fear response and identified an underlying neuronal circuit. METHODS Male and female mice were trained individually using auditory fear conditioning and then tested 24 hours later as dyads while allowing unrestricted social interaction during exposure to the conditioned stimulus under visible or infrared illumination to eliminate visual cues. The synchronization of the immobility or freezing bouts was quantified by calculating the effect size Cohen's d for the difference between the actual freezing time overlap and the overlap by chance. The inactivation of the dorsomedial prefrontal cortex, dorsal hippocampus, or ventral hippocampus was achieved by local infusions of muscimol. The chemogenetic disconnection of the hippocampus-amygdala pathway was performed by expressing hM4D(Gi) in the ventral hippocampal neurons and infusing clozapine N-oxide in the amygdala. RESULTS Mice synchronized cued but not contextual fear. It was higher in males than in females and attenuated in the absence of visible light. Inactivation of the ventral but not dorsal hippocampus or dorsomedial prefrontal cortex abolished fear synchronization. Finally, the disconnection of the hippocampus-amygdala pathway diminished fear synchronization. CONCLUSIONS Mice synchronize expression of conditioned fear relying on the ventral hippocampus-amygdala pathway, suggesting that the hippocampus transmits social information to the amygdala to synchronize threat response.
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Affiliation(s)
- Wataru Ito
- Fralin Biomedical Research Institute at Virginia Tech Carilion Center for Neurobiology Research, Roanoke, Virginia.
| | - Alexander J Palmer
- Fralin Biomedical Research Institute at Virginia Tech Carilion Center for Neurobiology Research, Roanoke, Virginia
| | - Alexei Morozov
- Fralin Biomedical Research Institute at Virginia Tech Carilion Center for Neurobiology Research, Roanoke, Virginia; Carilion Clinic Department of Psychiatry and Behavioral Medicine, Roanoke, Virginia.
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16
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Asgharpour-Masouleh N, Rezayof A, Alijanpour S, Delphi L. Pharmacological activation of mediodorsal thalamic GABA-A receptors modulates morphine/cetirizine-induced changes in the prefrontal cortical GFAP expression in a rat model of neuropathic pain. Behav Brain Res 2023; 438:114213. [PMID: 36372242 DOI: 10.1016/j.bbr.2022.114213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 10/21/2022] [Accepted: 11/08/2022] [Indexed: 11/13/2022]
Abstract
The present study investigated the involvement of mediodorsal thalamic (MD) GABA-A receptors in cetirizine/morphine-induced anti-allodynia using a rat model of neuropathic pain. To assess the importance of the prefrontal cortex (PFC) for chronic pain processing, its expression level changes of glial fibrillary acidic protein (GFAP) were measured following drug treatments. Each animal was subjected to chronic constriction of the sciatic nerve surgery simultaneously with the MD cannulation under stereotaxic surgery. The results showed that the administration of morphine (3-5 mg/kg) or cetirizine (1-3 mg/kg) produced significant analgesia in neuropathic rats. Systemic administration of cetirizine (2.5 and 3 mg/kg) potentiated the analgesic response to a low and intolerance dose of morphine (3 mg/kg). Intra-MD microinjection of muscimol, a selective GABA-A receptor agonist (0.005-0.01 μg/rat), increased the cetirizine/morphine-induced anti-allodynia, while muscimol by itself did not affect neuropathic pain. The neuropathic pain was associated with the increased PFC expression level of GFAP, suggesting the impact of chronic pain on PFC glial management. Interestingly, the anti-allodynia was associated with a decrease in the PFC expression level of GFAP under the drugs' co-administration. Thus, cetirizine has a significant potentiating effect on morphine response in neuropathic pain via interacting with the MD GABA-A receptors. It seems that neuropathic pain affects the prefrontal cortex GFAP signaling pathway. In clinical studies, these findings can be considered to create a combination therapy with low doses of GABA-A receptor agonist plus cetirizine and morphine to manage neuropathic pain.
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Affiliation(s)
| | - Ameneh Rezayof
- Department of Animal Biology, School of Biology, College of Science, University of Tehran, Tehran, Iran.
| | - Sakineh Alijanpour
- Department of Biology, Faculty of Science, Gonbad Kavous University, Gonbad Kavous, Iran
| | - Ladan Delphi
- Department of Animal Biology, School of Biology, College of Science, University of Tehran, Tehran, Iran
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17
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Gernert M, MacKeigan D, Deking L, Kaczmarek E, Feja M. Acute and chronic convection-enhanced muscimol delivery into the rat subthalamic nucleus induces antiseizure effects associated with high responder rates. Epilepsy Res 2023; 190:107097. [PMID: 36736200 DOI: 10.1016/j.eplepsyres.2023.107097] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 01/13/2023] [Accepted: 01/23/2023] [Indexed: 01/27/2023]
Abstract
Intracerebral drug delivery is an emerging treatment strategy aiming to manage seizures in patients with systemic drug-resistant epilepsies. In rat seizure and epilepsy models, the GABAA receptor agonist muscimol has shown powerful antiseizure potential when injected acutely into the subthalamic nucleus (STN), known for its capacity to provide remote control of different seizure types. However, chronic intrasubthalamic muscimol delivery required for long-term seizure suppression has not yet been investigated. We tested the hypothesis that chronic convection-enhanced delivery (CED) of muscimol into the STN produces long-lasting antiseizure effects in the intravenous pentylenetetrazole seizure threshold test in female rats. Acute microinjection was included to verify efficacy of intrasubthalamic muscimol delivery in this seizure model and caused significant antiseizure effects at 30 and 60 ng per hemisphere with a dose-dependent increase of responders and efficacy and only mild adverse effects compared to controls. For the chronic study, muscimol was bilaterally infused into the STN over three weeks at daily doses of 60, 300, or 600 ng per hemisphere using an implantable pump and cannula system. Chronic intrasubthalamic CED of muscimol caused significant long-lasting antiseizure effects for up to three weeks at 300 and 600 ng daily. Drug responder rate increased dose-dependently, as did drug tolerance rates. Transient ataxia and body weight loss were the main adverse effects. Drug distribution was comparable (about 2-3 mm) between acute and chronic delivery. This is the first study providing proof-of-concept that not only acute, but also chronic, continuous CED of muscimol into the STN raises seizure thresholds.
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Affiliation(s)
- Manuela Gernert
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Bünteweg 17, D-30559 Hannover, Germany; Center for Systems Neuroscience, University of Veterinary Medicine Hannover, Bünteweg 2, D-30559 Hannover, Germany.
| | - Devlin MacKeigan
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Bünteweg 17, D-30559 Hannover, Germany; Center for Systems Neuroscience, University of Veterinary Medicine Hannover, Bünteweg 2, D-30559 Hannover, Germany
| | - Lillian Deking
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Bünteweg 17, D-30559 Hannover, Germany
| | - Edith Kaczmarek
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Bünteweg 17, D-30559 Hannover, Germany
| | - Malte Feja
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Bünteweg 17, D-30559 Hannover, Germany; Center for Systems Neuroscience, University of Veterinary Medicine Hannover, Bünteweg 2, D-30559 Hannover, Germany.
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18
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Okhovat A, Cruces W, Docampo-Palacios ML, Ray KP, Ramirez GA. Psychoactive Isoxazoles, Muscimol, and Isoxazole Derivatives from the Amanita (Agaricomycetes) Species: Review of New Trends in Synthesis, Dosage, and Biological Properties. Int J Med Mushrooms 2023; 25:1-10. [PMID: 37824402 DOI: 10.1615/intjmedmushrooms.2023049458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2023]
Abstract
Herbal products found in nature can serve as great systems of study for drug design. The Amanita muscaria mushroom is native to many parts of the Northern Hemisphere and has a very distinctive appearance with its red cap and white spotted warts. The mushroom comprises several pharmacologically active alkaloids, including muscazone, muscarine, ibotenic acid, and muscimol, the latter two compounds being potent GABA agonists. Muscimol has served as a backbone in the design of GABA agonists devoid of effects on the GABA-metabolizing enzyme, GABA transaminase, and GABA uptake systems. In this sense, several analogs of muscimol have been synthesized and studied including THIP, THPO, iso-THIP, iso-THAZ and 4-PIOL which all interact with the GABA receptors much differently. The growing pharmacological and toxicological interest based on many conflicting opinions on the use of the neuroprotective role of muscimol analogs against some neurodegenerative diseases, its potent role in the treatment of cerebral ischemia and other socially significant health conditions provided the basis for this review.
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Affiliation(s)
- Alex Okhovat
- Colorado Chromatography Labs, Parker, CO 80134, USA
| | | | | | - Kyle P Ray
- Colorado Chromatography Labs, Parker, CO 80134, USA
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19
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Takemura A, Sugiyama Y, Yamamoto R, Kinoshita S, Kaneko M, Fuse S, Hashimoto K, Mukudai S, Umezaki T, Dutschmann M, Hirano S. Effect of pharmacological inhibition of the pontine respiratory group on swallowing interneurons in the dorsal medulla oblongata. Brain Res 2022; 1797:148101. [PMID: 36183794 DOI: 10.1016/j.brainres.2022.148101] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 08/31/2022] [Accepted: 09/26/2022] [Indexed: 11/15/2022]
Abstract
OBJECTIVES To examine the role of neurons of the pontine respiratory group (PRG) overlapping with the Kölliker-Fuse nucleus in the regulation of swallowing, we compared the activity of swallowing motor activities and interneuron discharge in the dorsal swallowing group in the medulla before and after pharmacological inhibition of the PRG. METHODS In 23 in situ perfused brainstem preparation of rats, we recorded the activities of the vagus (VNA), hypoglossal (HNA), and phrenic nerves (PNA), and swallowing interneurons of the dorsal medulla during fictive swallowing elicited by electrical stimulation of the superior laryngeal nerve or oral water injection. Subsequently, respiratory- and swallow-related motor activities and single unit cell discharge were assessed before and after local microinjection of the GABA-receptor agonist muscimol into the area of PRG ipsilateral to the recording sites of swallowing interneurons. RESULTS After muscimol injection, the amplitude and duration of swallow-related VNA bursts decreased to 71.3 ± 2.84 and 68.1 ± 2.76 % during electrically induced swallowing and VNA interburst intervals during repetitive swallowing decreased. Similar effects were observed for swallowing-related HNA. The swallowing motor activity was similarly qualitatively altered during physiologically induced swallowing. All 23 neurons were changed in either discharge duration or frequency after PRG inhibition, however, the general discharge patterns in relation to the motor output remained unchanged. CONCLUSION Descending synaptic inputs from PRG provide control of the primary laryngeal sensory gate and synaptic activity of the PRG partially determine medullary cell and cranial motor nerve activities that govern the pharyngeal stage of swallowing.
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Affiliation(s)
- Akiyo Takemura
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Yoichiro Sugiyama
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan.
| | - Ryota Yamamoto
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan; Department of Otolaryngology, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-5852, Japan
| | - Shota Kinoshita
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Mami Kaneko
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Shinya Fuse
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Keiko Hashimoto
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Shigeyuki Mukudai
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Toshiro Umezaki
- Department of Speech and Hearing Sciences, International University of Health and Welfare, and the Voice and Swallowing Center, Fukuoka Sanno Hospital, Fukuoka 814-0001, Japan
| | - Mathias Dutschmann
- Florey Institute of Neuroscience and Mental Health, Gate 11, Royal Parade, University of Melbourne, Victoria 3052, Australia
| | - Shigeru Hirano
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
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20
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Wei H, Chen Z, Lei J, You HJ, Pertovaara A. Reduced mechanical hypersensitivity by inhibition of the amygdala in experimental neuropathy: Sexually dimorphic contribution of spinal neurotransmitter receptors. Brain Res 2022; 1797:148128. [PMID: 36265669 DOI: 10.1016/j.brainres.2022.148128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 09/27/2022] [Accepted: 10/13/2022] [Indexed: 11/20/2022]
Abstract
Here we studied spinal neurotransmitter mechanisms involved in the reduction of mechanical hypersensitivity by inhibition of the amygdaloid central nucleus (CeA) in male and female rats with spared nerve injury (SNI) model of neuropathy. SNI induced mechanical hypersensitivity that was stronger in females. Reversible blocking of the CeA with muscimol (GABAA receptor agonist) induced a reduction of mechanical hypersensitivity that did not differ between males and females. Following spinal co-administration of atipamezole (α2-adrenoceptor antagonist), the reduction of mechanical hypersensitivity by CeA muscimol was attenuated more in males than females. In contrast, following spinal co-administration of raclopride (dopamine D2 receptor antagonist) the reduction of hypersensitivity by CeA muscimol was attenuated more in females than males. The reduction of mechanical hypersensitivity by CeA muscimol was equally attenuated in males and females by spinal co-administration of WAY-100635 (5-HT1A receptor antagonist) or bicuculline (GABAA receptor antagonist). The CeA muscimol induced attenuation of ongoing pain-like behavior (conditioned place preference test) that was reversed by spinal co-administration of atipamezole in both sexes. The results support the hypothesis that CeA contributes to mechanical hypersensitivity and ongoing pain-like behavior in SNI males and females. Disinhibition of descending controls acting on spinal α2-adrenoceptors, 5-HT1A, dopamine D2 and GABAA receptors provides a plausible explanation for the reduction of mechanical hypersensitivity by CeA block in SNI. The involvement of spinal dopamine D2 receptors and α2-adrenoceptors in the CeA muscimol-induced reduction of mechanical hypersensitivity is sexually dimorphic, unlike that of spinal α2-adrenoceptors in the reduction of ongoing neuropathic pain.
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Affiliation(s)
- Hong Wei
- Department of Physiology, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Zuyue Chen
- Department of Physiology, Faculty of Medicine, University of Helsinki, Helsinki, Finland; Department of Medical Imaging, School of Medicine, Shaoxing University, Shaoxing, PR China
| | - Jing Lei
- Department of Physiology, Faculty of Medicine, University of Helsinki, Helsinki, Finland; Center for Translational Medicine Research on Sensory-Motor Diseases, Yan'an University, Yan'an, PR China
| | - Hao-Jun You
- Center for Translational Medicine Research on Sensory-Motor Diseases, Yan'an University, Yan'an, PR China
| | - Antti Pertovaara
- Department of Physiology, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
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21
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Wollman LB, Flanigan EG, Fregosi RF. Chronic, episodic nicotine exposure alters GABAergic synaptic transmission to hypoglossal motor neurons and genioglossus muscle function at a critical developmental age. J Neurophysiol 2022; 128:1483-1500. [PMID: 36350047 PMCID: PMC9722256 DOI: 10.1152/jn.00397.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 11/02/2022] [Accepted: 11/03/2022] [Indexed: 11/11/2022] Open
Abstract
Regulation of GABAergic signaling through nicotinic acetylcholine receptor (nAChR) activation is critical for neuronal development. Here, we test the hypothesis that chronic episodic developmental nicotine exposure (eDNE) disrupts GABAergic signaling, leading to dysfunction of hypoglossal motor neurons (XIIMNs), which innervate the tongue muscles. We studied control and eDNE pups at two developmentally vulnerable age ranges: postnatal days (P)1-5 and P10-12. The amplitude and frequency of spontaneous and miniature inhibitory postsynaptic currents (sIPSCs, mIPSCs) at baseline were not altered by eDNE at either age. In contrast, eDNE increased GABAAR-α1 receptor expression on XIIMNs and, in the older group, the postsynaptic response to muscimol (GABAA receptor agonist). Activation of nAChRs with exogenous nicotine increased the frequency of GABAergic sIPSCs in control and eDNE neurons at P1-5. By P10-12, acute nicotine increased sIPSC frequency in eDNE but not control neurons. In vivo experiments showed that the breathing-related activation of tongue muscles, which are innervated by XIIMNs, is reduced at P10-12. This effect was partially mitigated by subcutaneous muscimol, but only in the eDNE pups. Taken together, these data indicate that eDNE alters GABAergic transmission to XIIMNs at a critical developmental age, and this is expressed as reduced breathing-related drive to XIIMNs in vivo.NEW & NOTEWORTHY Here, we provide a thorough assessment of the effects of nicotine exposure on GABAergic synaptic transmission, from the cellular to the systems level. This work makes significant advances in our understanding of the impact of nicotine exposure during development on GABAergic neurotransmission within the respiratory network and the potential role this plays in the excitatory/inhibitory imbalance that is thought to be an important mechanism underlying neonatal breathing disorders, including sudden infant death syndrome.
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Affiliation(s)
- Lila Buls Wollman
- Department of Physiology, The University of Arizona, Tucson, Arizona
| | | | - Ralph F Fregosi
- Department of Physiology, The University of Arizona, Tucson, Arizona
- Department of Neuroscience, The University of Arizona, Tucson, Arizona
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22
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Sun W, Li B, Ma C. Muscimol-induced inactivation of the ventral prefrontal cortex impairs counting performance in rhesus monkeys. Sci Prog 2022; 105:368504221141660. [PMID: 36443989 PMCID: PMC10358485 DOI: 10.1177/00368504221141660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/11/2023]
Abstract
Numbers are one of the three basic concepts of human abstract thinking. When human beings count, they often point to things, one by one, and read numbers in a positive integer column. The prefrontal cortex plays a wide range of roles in executive functions, including active maintenance and achievement of goals, adaptive coding and exertion of general intelligence, and completion of time complexity events. Nonhuman animals do not use number names, such as "one, two, three," or numerals, such as "1, 2, 3" to "count" in the same way as humans do. Our previous study established an animal model of counting in monkeys. Here, we used this model to determine whether the prefrontal cortex participates in counting in monkeys. Two 5-year-old female rhesus monkeys (macaques), weighing 5.0 kg and 5.5 kg, were selected to train in a counting task, counting from 1 to 5. When their counting task performance stabilized, we performed surgery on the prefrontal cortex to implant drug delivery tubes. After allowing the monkeys' physical condition and counting performance to recover, we injected either muscimol or normal saline into their dorsal and ventral prefrontal cortex. Thereafter, we observed their counting task performance and analyzed the error types and reaction time during the counting task. The monkeys' performance in the counting task decreased significantly after muscimol injection into the ventral prefrontal cortex; however, it was not affected after saline injection into the ventral prefrontal cortex, or after muscimol or saline injection into the dorsal prefrontal cortex. The ventral prefrontal cortex of the monkey is necessary for counting performance.
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Affiliation(s)
- Weiming Sun
- School of Life Science, Nanchang University, Nanchang, China
- Center for Neuropsychiatric Disorders, Institute of Life Science, Nanchang University, Nanchang, China
| | - Baoming Li
- School of Life Science, Nanchang University, Nanchang, China
- Center for Neuropsychiatric Disorders, Institute of Life Science, Nanchang University, Nanchang, China
| | - Chaolin Ma
- School of Life Science, Nanchang University, Nanchang, China
- Center for Neuropsychiatric Disorders, Institute of Life Science, Nanchang University, Nanchang, China
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23
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Lemercier CE, Garenne A, Poulletier de Gannes F, El Khoueiry C, Arnaud-Cormos D, Levêque P, Lagroye I, Percherancier Y, Lewis N. Comparative study between radiofrequency-induced and muscimol-induced inhibition of cultured networks of cortical neuron. PLoS One 2022; 17:e0268605. [PMID: 36044461 PMCID: PMC9432733 DOI: 10.1371/journal.pone.0268605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 08/17/2022] [Indexed: 11/30/2022] Open
Abstract
Previous studies have shown that spontaneously active cultured networks of cortical neuron grown planar microelectrode arrays are sensitive to radiofrequency (RF) fields and exhibit an inhibitory response more pronounced as the exposure time and power increase. To better understand the mechanism behind the observed effects, we aimed at identifying similarities and differences between the inhibitory effect of RF fields (continuous wave, 1800 MHz) to the γ-aminobutyric acid type A (GABAA) receptor agonist muscimol (MU). Inhibition of the network bursting activity in response to RF exposure became apparent at an SAR level of 28.6 W/kg and co-occurred with an elevation of the culture medium temperature of ~1°C. Exposure to RF fields preferentially inhibits bursting over spiking activity and exerts fewer constraints on neural network bursting synchrony, differentiating it from a pharmacological inhibition with MU. Network rebound excitation, a phenomenon relying on the intrinsic properties of cortical neurons, was observed following the removal of tonic hyperpolarization after washout of MU but not in response to cessation of RF exposure. This implies that hyperpolarization is not the main driving force mediating the inhibitory effects of RF fields. At the level of single neurons, network inhibition induced by MU and RF fields occurred with reduced action potential (AP) half-width. As changes in AP waveform strongly influence efficacy of synaptic transmission, the narrowing effect on AP seen under RF exposure might contribute to reducing network bursting activity. By pointing only to a partial overlap between the inhibitory hallmarks of these two forms of inhibition, our data suggest that the inhibitory mechanisms of the action of RF fields differ from the ones mediated by the activation of GABAA receptors.
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Affiliation(s)
- Clément E. Lemercier
- Laboratoire de l’Intégration du Matériau au Système, CNRS UMR 5218, University of Bordeaux, Talence, France
- Faculty of Medicine, Institute of Physiology, Department of Systems Neuroscience, Ruhr University Bochum, Bochum, Germany
- * E-mail: (CEL); (NL)
| | - André Garenne
- Laboratoire de l’Intégration du Matériau au Système, CNRS UMR 5218, University of Bordeaux, Talence, France
| | | | - Corinne El Khoueiry
- Laboratoire de l’Intégration du Matériau au Système, CNRS UMR 5218, University of Bordeaux, Talence, France
| | - Delia Arnaud-Cormos
- Univ. Limoges, CNRS, XLIM, UMR 7252, Limoges, France
- Institut Universitaire de France (IUF), Paris, France
| | | | - Isabelle Lagroye
- Laboratoire de l’Intégration du Matériau au Système, CNRS UMR 5218, University of Bordeaux, Talence, France
- Paris “Sciences et Lettres” Research University, Paris, France
| | - Yann Percherancier
- Laboratoire de l’Intégration du Matériau au Système, CNRS UMR 5218, University of Bordeaux, Talence, France
| | - Noëlle Lewis
- Laboratoire de l’Intégration du Matériau au Système, CNRS UMR 5218, University of Bordeaux, Talence, France
- * E-mail: (CEL); (NL)
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24
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Al-Absi AR, Thambiappa SK, Khan AR, Glerup S, Sanchez C, Landau AM, Nyengaard JR. Df(h22q11)/+ mouse model exhibits reduced binding levels of GABA A receptors and structural and functional dysregulation in the inhibitory and excitatory networks of hippocampus. Mol Cell Neurosci 2022; 122:103769. [PMID: 35988854 DOI: 10.1016/j.mcn.2022.103769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Revised: 08/11/2022] [Accepted: 08/14/2022] [Indexed: 11/17/2022] Open
Abstract
The 22q11.2 hemizygous deletion confers high risk for multiple neurodevelopmental disorders. Inhibitory signaling, largely regulated through GABAA receptors, is suggested to serve a multitude of brain functions that are disrupted in the 22q11.2 deletion syndrome. We investigated the putative deficit of GABAA receptors and the potential substrates contributing to the inhibitory and excitatory dysregulations in hippocampal networks of the Df(h22q11)/+ mouse model of the 22q11.2 hemizygous deletion. The Df(h22q11)/+ mice exhibited impairments in several hippocampus-related functional domains, represented by impaired spatial memory and sensory gating functions. Autoradiography using the [3H]muscimol tracer revealed a significant reduction in GABAA receptor binding in the CA1 and CA3 subregions, together with a loss of GAD67+ interneurons in CA1 of Df(h22q11)/+ mice. Furthermore, electrophysiology recordings exhibited significantly higher neuronal activity in CA3, in response to the GABAA receptor antagonist, bicuculline, as compared with wild type mice. Density and volume of dendritic spines in pyramidal neurons were reduced and Sholl analysis also showed a reduction in the complexity of basal dendritic tree in CA1 and CA3 subregions of Df(h22q11)/+ mice. Overall, our findings demonstrate that hemizygous deletion in the 22q11.2 locus leads to dysregulations in the inhibitory circuits, involving reduced binding levels of GABAA receptors, in addition to functional and structural modulations of the excitatory networks of hippocampus.
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Affiliation(s)
- Abdel-Rahman Al-Absi
- Center for Molecular Morphology, Section for Stereology and Microscopy, Department of Clinical Medicine, Aarhus University, Denmark; Department of Pathology, Aarhus University Hospital, Denmark.
| | - Sakeerthi Kethees Thambiappa
- Center for Molecular Morphology, Section for Stereology and Microscopy, Department of Clinical Medicine, Aarhus University, Denmark; Department of Pathology, Aarhus University Hospital, Denmark.
| | - Ahmad Raza Khan
- Centre of Biomedical Research (CBMR), SGPGIMS Campus, Lucknow, India.
| | - Simon Glerup
- Department of Biomedicine, Aarhus University, Denmark.
| | - Connie Sanchez
- Translational Neuropsychiatry Unit, Aarhus University, Denmark.
| | - Anne M Landau
- Translational Neuropsychiatry Unit, Aarhus University, Denmark; Department of Nuclear Medicine and PET Centre, Aarhus University Hospital, Denmark.
| | - Jens R Nyengaard
- Center for Molecular Morphology, Section for Stereology and Microscopy, Department of Clinical Medicine, Aarhus University, Denmark; Department of Pathology, Aarhus University Hospital, Denmark.
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25
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Loeza-Alcocer E, Gold MS. Peripheral GABAA receptor signaling contributes to visceral hypersensitivity in a mouse model of colitis. Pain 2022; 163:1402-1413. [PMID: 34726659 PMCID: PMC9056586 DOI: 10.1097/j.pain.0000000000002526] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 09/16/2021] [Indexed: 11/26/2022]
Abstract
ABSTRACT Pain is a common and debilitating symptom of inflammatory bowel disease (IBD). Based on evidence that peripheral GABAA receptor (GAR) inhibition plays an important role in establishing colonic afferent excitability and nociceptive threshold, we hypothesized that the increase in pain associated with IBD is due to, at least in part, a decrease in peripheral GAR-mediated inhibition. Acute colitis was induced with 5 days of dextran sodium sulfate (DSS, 3%) in the drinking water. Visceral sensitivity was assessed with the visceromotor response (VMR) evoked with balloon distention of the colon in control and DSS-treated mice before and after intracolonic administration of GAR agonist muscimol, the high-affinity GAR preferring agonist 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridine-3-ol (THIP), the GAR positive allosteric modulator diazepam, or the GAR antagonists gabazine and bicuculline. Low concentrations of muscimol or THIP increased the VMR in DSS-treated mice but not in control mice. However, high concentrations of muscimol decreased the VMR in both control and DSS-treated mice. Diazepam decreased the VMR in both DSS-treated and control mice. By contrast, at a concentration of gabazine that blocks only low-affinity GAR, there was no effect on the VMR in either DSS-treated or control mice, but at concentrations of the antagonist that block low-affinity and high-affinity GAR, the VMR was increased in control mice and decreased in DSS-treated mice. Furthermore, bicuculline increased the VMR in control mice but decreased it in DSS-treated mice. These data suggest that activating of low-affinity GAR or blocking high-affinity GAR may be effective therapeutic strategies for the management of pain in IBD.
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Affiliation(s)
- Emanuel Loeza-Alcocer
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Michael S Gold
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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26
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Ihara M, Tanaka K, Kai K, Hayashi H, Matsuda K. Competitive chrodrimanin B interactions with rat brain GABA A receptors revealed by radioligand binding assays. Pestic Biochem Physiol 2022; 183:105074. [PMID: 35430068 DOI: 10.1016/j.pestbp.2022.105074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 02/25/2022] [Accepted: 03/01/2022] [Indexed: 06/14/2023]
Abstract
Meroterpenoid compounds chrodrimanins produced by Talaromyces sp. YO-2 have been shown to act as competitive antagonists of silkworm larval GABAA receptors using electrophysiology, yet no further evidence has been provided to support such an action. We have investigated the actions of chrodrimanin B on rat brain GABAA receptors by binding assays with non-competitive ligand of GABAA receptors [3H]EBOB and competitive ligands [3H]gabazine and [3H]muscimol. Chrodrimanin B did not significantly affect the binding of [3H]EBOB while reducing the binding of [3H]gabazine and [3H]muscimol to the rat membrane preparations. Chrodrimanin B increased the dissociation constant Kd of [3H]gabazine and [3H]muscimol without significantly affecting the maximum binding, pointing to competitive interactions of chrodrimanin B with rat GABAA receptors in support of our previous observation that the compound acts as a competitive antagonist on the silkworm larval GABA receptor.
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Affiliation(s)
- Makoto Ihara
- Department of Applied Biological Chemistry, Faculty of Agriculture, Kindai University 3327-204 Nakamachi, Nara 631-8505, Japan
| | - Keiji Tanaka
- Department of Applied Biological Chemistry, Faculty of Agriculture, Kindai University 3327-204 Nakamachi, Nara 631-8505, Japan
| | - Kenji Kai
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Osaka, 599-8531, Japan
| | - Hideo Hayashi
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Osaka, 599-8531, Japan
| | - Kazuhiko Matsuda
- Department of Applied Biological Chemistry, Faculty of Agriculture, Kindai University 3327-204 Nakamachi, Nara 631-8505, Japan; Agricultural Technology and Innovation Research Institute, Kindai University, 3327-204 Nakamachi, Nara 631-8505, Japan.
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27
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Rieger NS, Worley NB, Ng AJ, Christianson JP. Insular cortex modulates social avoidance of sick rats. Behav Brain Res 2022; 416:113541. [PMID: 34425184 PMCID: PMC8492531 DOI: 10.1016/j.bbr.2021.113541] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/29/2021] [Accepted: 08/18/2021] [Indexed: 02/07/2023]
Abstract
Avoidance of sick individuals is vital to the preservation of one's health and preventing transmission of communicable diseases. To do this successfully, one must identify social cues for sickness, which include sickness behaviors and chemosignals, and use this information to orchestrate social interactions. While many social species are highly capable with this process, the neural mechanisms that provide for social responses to sick individuals are only partially understood. To this end, we used a task in which experimental rats were allowed to investigate two conspecifics, one healthy and one sick. To imitate sickness, one conspecific received the viral mimic Polyinosinic:polycytidylic acid (Poly I:C) and the other saline. In a 5-minute social preference test, experimental male and female adult rats avoided Poly I:C treated adult conspecifics but did not adjust social interaction in response to Poly I:C treated juvenile conspecifics. Seeking a neural locus of this behavior, we inhibited the insular cortex, a region necessary for social behaviors directed toward conspecifics in distress. Insular cortex inactivation via administration of the GABAA agonist muscimol to experimental rats prior to social preference tests eliminated the preference to avoid sick adult conspecifics. These results suggest that some aspect of conspecific illness may be encoded in the insular cortex which is anatomically positioned to coordinate a situationally appropriate social response.
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Affiliation(s)
- Nathaniel S Rieger
- Department of Psychology and Neuroscience, Boston College, 140 Commonwealth Avenue, Chestnut Hill, MA, 02467 USA
| | - Nicholas B Worley
- Department of Psychology and Neuroscience, Boston College, 140 Commonwealth Avenue, Chestnut Hill, MA, 02467 USA
| | - Alexandra J Ng
- Department of Psychology and Neuroscience, Boston College, 140 Commonwealth Avenue, Chestnut Hill, MA, 02467 USA
| | - John P Christianson
- Department of Psychology and Neuroscience, Boston College, 140 Commonwealth Avenue, Chestnut Hill, MA, 02467 USA.
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28
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Vacher CM, Lacaille H, O'Reilly JJ, Salzbank J, Bakalar D, Sebaoui S, Liere P, Clarkson-Paredes C, Sasaki T, Sathyanesan A, Kratimenos P, Ellegood J, Lerch JP, Imamura Y, Popratiloff A, Hashimoto-Torii K, Gallo V, Schumacher M, Penn AA. Placental endocrine function shapes cerebellar development and social behavior. Nat Neurosci 2021; 24:1392-1401. [PMID: 34400844 PMCID: PMC8481124 DOI: 10.1038/s41593-021-00896-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 06/23/2021] [Indexed: 02/07/2023]
Abstract
Compromised placental function or premature loss has been linked to diverse neurodevelopmental disorders. Here we show that placenta allopregnanolone (ALLO), a progesterone-derived GABA-A receptor (GABAAR) modulator, reduction alters neurodevelopment in a sex-linked manner. A new conditional mouse model, in which the gene encoding ALLO's synthetic enzyme (akr1c14) is specifically deleted in trophoblasts, directly demonstrated that placental ALLO insufficiency led to cerebellar white matter abnormalities that correlated with autistic-like behavior only in male offspring. A single injection of ALLO or muscimol, a GABAAR agonist, during late gestation abolished these alterations. Comparison of male and female human preterm infant cerebellum also showed sex-linked myelination marker alteration, suggesting similarities between mouse placental ALLO insufficiency and human preterm brain development. This study reveals a new role for a placental hormone in shaping brain regions and behaviors in a sex-linked manner. Placental hormone replacement might offer novel therapeutic opportunities to prevent later neurobehavioral disorders.
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Affiliation(s)
- Claire-Marie Vacher
- Department of Pediatrics, Columbia University, New York-Presbyterian Morgan Stanley Children's Hospital, New York, NY, USA.
| | - Helene Lacaille
- Department of Pediatrics, Columbia University, New York-Presbyterian Morgan Stanley Children's Hospital, New York, NY, USA
| | - Jiaqi J O'Reilly
- Department of Pediatrics, Columbia University, New York-Presbyterian Morgan Stanley Children's Hospital, New York, NY, USA
| | - Jacquelyn Salzbank
- Department of Pediatrics, Columbia University, New York-Presbyterian Morgan Stanley Children's Hospital, New York, NY, USA
| | - Dana Bakalar
- National Institutes of Health, Bethesda, MD, USA
| | - Sonia Sebaoui
- Center for Neuroscience Research, Children's National Health System, Washington, DC, USA
| | - Philippe Liere
- U1195 INSERM, Paris-Saclay University, Le Kremlin-Bicêtre Cedex, France
| | | | - Toru Sasaki
- Center for Neuroscience Research, Children's National Health System, Washington, DC, USA
| | - Aaron Sathyanesan
- Center for Neuroscience Research, Children's National Health System, Washington, DC, USA
| | - Panagiotis Kratimenos
- Center for Neuroscience Research, Children's National Health System, Washington, DC, USA
- The George Washington University School of Medicine and Health Sciences, Pediatrics, Washington, DC, USA
| | - Jacob Ellegood
- Mouse Imaging Centre (MICe), Hospital for Sick Children, Toronto, ON, Canada
| | - Jason P Lerch
- Mouse Imaging Centre (MICe), Hospital for Sick Children, Toronto, ON, Canada
- Wellcome Centre for Integrative Neuroimaging (WIN), Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Yuka Imamura
- Department of Biochemistry and Molecular Biology, Pennsylvania State University College of Medicine, Pittsburgh, PA, USA
| | - Anastas Popratiloff
- The George Washington University, Nanofabrication and Imaging Center, Washington, DC, USA
- The George Washington University, SMHS, Anatomy & Cell Biology, Washington, DC, USA
| | - Kazue Hashimoto-Torii
- Center for Neuroscience Research, Children's National Health System, Washington, DC, USA
- The George Washington University School of Medicine and Health Sciences, Pediatrics, Washington, DC, USA
| | - Vittorio Gallo
- Center for Neuroscience Research, Children's National Health System, Washington, DC, USA
- The George Washington University School of Medicine and Health Sciences, Pediatrics, Washington, DC, USA
| | | | - Anna A Penn
- Department of Pediatrics, Columbia University, New York-Presbyterian Morgan Stanley Children's Hospital, New York, NY, USA.
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29
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Axelsson SFA, Horst NK, Horiguchi N, Roberts AC, Robbins TW. Flexible versus Fixed Spatial Self-Ordered Response Sequencing: Effects of Inactivation and Neurochemical Modulation of Ventrolateral Prefrontal Cortex. J Neurosci 2021; 41:7246-7258. [PMID: 34261701 PMCID: PMC8387118 DOI: 10.1523/jneurosci.0227-21.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 05/16/2021] [Accepted: 05/30/2021] [Indexed: 11/21/2022] Open
Abstract
Previously, studies using human neuroimaging and excitotoxic lesions in non-human primate have demonstrated an important role of ventrolateral prefrontal cortex (vlPFC) in higher order cognitive functions such as cognitive flexibility and the planning of behavioral sequences. In the present experiments, we tested effects on performance of temporary inactivation (using GABA receptor agonists) and dopamine (DA) D2 and 5-HT2A-receptor (R) blockade of vlPFC via local intracerebral infusions in the marmoset. We trained common marmosets to perform spatial self-ordered sequencing tasks in which one cohort of animals performed two and three response sequences on a continuously varying spatial array of response options on a touch-sensitive screen. Inactivation of vlPFC produced a marked disruption of accuracy of sequencing which also exhibited significant error perseveration. There were somewhat contrasting effects of D2 and 5-HT2A-R blockade, with the former producing error perseveration on incorrect trials, though not significantly impairing accuracy overall, and the latter significantly impairing accuracy but not error perseveration. A second cohort of marmosets were directly compared on performance of fixed versus variable spatial arrays. Inactivation of vlPFC again impaired self-ordered sequencing, but only with varying, and not fixed spatial arrays, the latter leading to the consistent use of fewer, preferred sequences. These findings add to evidence that vlPFC is implicated in goal-directed behavior that requires higher-order response heuristics that can be applied flexibly over different (variable), as compared with fixed stimulus exemplars. They also show that dopaminergic and serotonergic chemomodulation has distinctive effects on such performance.SIGNIFICANCE STATEMENT This investigation employing local intracerebral infusions to inactivate the lateral prefrontal cortex (PFC) of the New World marmoset reveals the important role of this region in self-ordered response sequencing in variable but not fixed spatial arrays. These novel findings emphasize the higher order functions of this region, contributing to cognitive flexibility and planning of goal directed behavior. The investigation also reports for the first time somewhat contrasting neuromodulatory deficits produced by infusions of dopamine (DA) D2 and 5-HT2A receptor (R) antagonists into the same region, of possible significance for understanding cognitive deficits produced by anti-psychotic drugs.
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Affiliation(s)
- S F A Axelsson
- Department of Psychology, University of Cambridge, Cambridge CB2 3EB, United Kingdom
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge CB2 3EB, United Kingdom
| | - N K Horst
- Department of Psychology, University of Cambridge, Cambridge CB2 3EB, United Kingdom
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge CB2 3EB, United Kingdom
| | - Naotaka Horiguchi
- Department of Psychology, University of Cambridge, Cambridge CB2 3EB, United Kingdom
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge CB2 3EB, United Kingdom
| | - A C Roberts
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, United Kingdom
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge CB2 3EB, United Kingdom
| | - T W Robbins
- Department of Psychology, University of Cambridge, Cambridge CB2 3EB, United Kingdom
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge CB2 3EB, United Kingdom
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30
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Cernotova D, Stuchlik A, Svoboda J. Transient Inactivation of the Medial Prefrontal Cortex and Ventral Hippocampus Impairs Active Place Avoidance Retrieval on a Rotating Arena. Front Neural Circuits 2021; 15:634533. [PMID: 33994956 PMCID: PMC8113689 DOI: 10.3389/fncir.2021.634533] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Accepted: 03/30/2021] [Indexed: 11/13/2022] Open
Abstract
It is well known that communication between the medial prefrontal cortex (mPFC) and the ventral hippocampus (vHPC) is critical for various cognitive and behavioral functions. However, the exact role of these structures in spatial coordination remains to be clarified. Here we sought to determine the involvement of the mPFC and the vHPC in the spatial retrieval of a previously learned active place avoidance task in adult male Long-Evans rats, using a combination of unilateral and bilateral local muscimol inactivations. Moreover, we tested the role of the vHPC-mPFC pathway by performing combined ipsilateral and contralateral inactivations. Our results showed not only bilateral inactivations of either structure, but also the combined inactivations impaired the retrieval of spatial memory, whereas unilateral one-structure inactivations did not yield any effect. Remarkably, muscimol injections in combined groups exerted similar deficits, regardless of whether the inactivations were contralateral or ipsilateral. These findings confirm the importance of these structures in spatial cognition and emphasize the importance of the intact functioning of the vHPC-mPFC pathway.
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Affiliation(s)
| | - Ales Stuchlik
- Laboratory of the Neurophysiology of Memory, Institute of Physiology of the Czech Academy of Sciences, Prague, Czechia
| | - Jan Svoboda
- Laboratory of the Neurophysiology of Memory, Institute of Physiology of the Czech Academy of Sciences, Prague, Czechia
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Sabihi S, Goodpaster C, Maurer S, Leuner B. GABA in the medial prefrontal cortex regulates anxiety-like behavior during the postpartum period. Behav Brain Res 2021; 398:112967. [PMID: 33075397 PMCID: PMC7722033 DOI: 10.1016/j.bbr.2020.112967] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 10/02/2020] [Accepted: 10/07/2020] [Indexed: 01/22/2023]
Abstract
The postpartum period is commonly accompanied by emotional changes, which for many new mothers includes a reduction in anxiety. Previous research in rodents has shown that the postpartum attenuation in anxiety is dependent on offspring contact and has further implicated enhanced GABAergic neurotransmission as an underlying mechanism. However, the specific brain regions where GABA acts to regulate the offspring-induced reduction in postpartum anxiety requires further investigation. Here, we test the hypothesis that offspring interactions suppress anxiety-like behavior in postpartum female rats via GABA signaling in the medial prefrontal cortex (mPFC). Our results show a postpartum reduction in anxiety-like behavior, an effect which was abolished by localized infusion of the GABAA receptor antagonist bicuculline in the mPFC. We also show that activation of GABAA receptors in the mPFC by the agonist muscimol was effective in restoring anxiolyisis in mothers separated from their pups. Lastly, we show that heightened anxiety-like behavior in pup-separated mothers was accompanied by a lower number and percentage of activated GABAergic neurons within the mPFC. Together, these results suggest that mother-offspring interactions reduce anxiety-like behavior in postpartum females via GABAA neurotransmission in the mPFC and in doing so provide insight into mechanisms that may become dysfunctional in mothers who experience high postpartum anxiety.
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Affiliation(s)
- Sara Sabihi
- Department of Psychology, The Ohio State University Columbus, OH 43210, USA
| | - Caitlin Goodpaster
- Department of Psychology, The Ohio State University Columbus, OH 43210, USA
| | - Skyler Maurer
- Department of Psychology, The Ohio State University Columbus, OH 43210, USA
| | - Benedetta Leuner
- Department of Psychology, The Ohio State University Columbus, OH 43210, USA; Department of Neuroscience, The Ohio State University Columbus, OH 43210, USA.
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Shinohara K, Yasoshima Y. Inactivation of the ventral hippocampus facilitates the attenuation of odor neophobia in rats. Behav Brain Res 2020; 401:113077. [PMID: 33345825 DOI: 10.1016/j.bbr.2020.113077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 12/07/2020] [Accepted: 12/12/2020] [Indexed: 11/20/2022]
Abstract
Food neophobia is a behavior observed in rodents involving reduced consumption of a novel food or drink. In the absence of negative post-ingestive consequences, consumption increases with exposure (attenuation of neophobia), which is seen as an associative safe memory. Olfaction and gustation are sensory modalities essential for the development of a food preference. However, little is known about the neural mechanisms underlying neophobia to a food-related odor stimulus. In the present study, we examined the effect of pharmacological inactivation of the ventral hippocampus (vHPC) on neophobia to orally consumed solutions in rats using muscimol, a gamma aminobutyric acid type A receptor agonist. Two different types of solutions, almond odor (benzaldehyde) and sweet taste (saccharin), were prepared. In the results, microinjections of muscimol into the bilateral vHPC before the first odor and taste exposures did not alter the neophobic reactions of the rats to each stimulus. However, in the second odor, but not taste, exposure, the muscimol-injected rats showed higher consumption in comparison to that observed in the control rats, suggesting that the vHPC inactivation facilitates the attenuation of odor neophobia. On the other hand, intra-vHPC muscimol microinjections after the first odor and taste exposures did not facilitate consumption at the second exposures. These results indicate that neural activations within vHPC during orally consuming a novel odor, but not taste, solution play an inhibitory role in the subsequent attenuation of neophobia.
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Affiliation(s)
- Keisuke Shinohara
- Division of Behavioral Physiology, Department of Behavioral Sciences, Graduate School of Human Sciences, Osaka University, 1-2 Yamadaoka, Suita, Osaka, Japan
| | - Yasunobu Yasoshima
- Division of Behavioral Physiology, Department of Behavioral Sciences, Graduate School of Human Sciences, Osaka University, 1-2 Yamadaoka, Suita, Osaka, Japan.
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Akk G, Germann AL, Sugasawa Y, Pierce SR, Evers AS, Steinbach JH. Enhancement of Muscimol Binding and Gating by Allosteric Modulators of the GABA A Receptor: Relating Occupancy to State Functions. Mol Pharmacol 2020; 98:303-313. [PMID: 32873746 PMCID: PMC7472144 DOI: 10.1124/molpharm.120.000066] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 07/17/2020] [Indexed: 01/08/2023] Open
Abstract
Muscimol is a psychoactive isoxazole derived from the mushroom Amanita muscaria and a potent orthosteric agonist of the GABAA receptor. The binding of [3H]muscimol has been used to evaluate the distribution of GABAA receptors in the brain, and studies of modulation of [3H]muscimol binding by allosteric GABAergic modulators such as barbiturates and steroid anesthetics have provided insight into the modes of action of these drugs on the GABAA receptor. It has, however, not been feasible to directly apply interaction parameters derived from functional studies to describe the binding of muscimol to the receptor. Here, we employed the Monod-Wyman-Changeux concerted transition model to analyze muscimol binding isotherms. We show that the binding isotherms from recombinant α1β3 GABAA receptors can be qualitatively predicted using electrophysiological data pertaining to properties of receptor activation and desensitization in the presence of muscimol. The model predicts enhancement of [3H]muscimol binding in the presence of the steroids allopregnanolone and pregnenolone sulfate, although the steroids interact with distinct sites and either enhance (allopregnanolone) or reduce (pregnenolone sulfate) receptor function. We infer that the concerted transition model can be used to link radioligand binding and electrophysiological data. SIGNIFICANCE STATEMENT: The study employs a three-state resting-active-desensitized model to link radioligand binding and electrophysiological data. We show that the binding isotherms can be qualitatively predicted using parameters estimated in electrophysiological experiments and that the model accurately predicts the enhancement of [3H]muscimol binding in the presence of the potentiating steroid allopregnanolone and the inhibitory steroid pregnenolone sulfate.
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Affiliation(s)
- Gustav Akk
- Department of Anesthesiology (G.A., A.L.G., Y.S., S.R.P., A.S.E., J.H.S.) and the Taylor Family Institute for Innovative Psychiatric Research (G.A., A.S.E., J.H.S.), Washington University School of Medicine, St. Louis, Missouri
| | - Allison L Germann
- Department of Anesthesiology (G.A., A.L.G., Y.S., S.R.P., A.S.E., J.H.S.) and the Taylor Family Institute for Innovative Psychiatric Research (G.A., A.S.E., J.H.S.), Washington University School of Medicine, St. Louis, Missouri
| | - Yusuke Sugasawa
- Department of Anesthesiology (G.A., A.L.G., Y.S., S.R.P., A.S.E., J.H.S.) and the Taylor Family Institute for Innovative Psychiatric Research (G.A., A.S.E., J.H.S.), Washington University School of Medicine, St. Louis, Missouri
| | - Spencer R Pierce
- Department of Anesthesiology (G.A., A.L.G., Y.S., S.R.P., A.S.E., J.H.S.) and the Taylor Family Institute for Innovative Psychiatric Research (G.A., A.S.E., J.H.S.), Washington University School of Medicine, St. Louis, Missouri
| | - Alex S Evers
- Department of Anesthesiology (G.A., A.L.G., Y.S., S.R.P., A.S.E., J.H.S.) and the Taylor Family Institute for Innovative Psychiatric Research (G.A., A.S.E., J.H.S.), Washington University School of Medicine, St. Louis, Missouri
| | - Joe Henry Steinbach
- Department of Anesthesiology (G.A., A.L.G., Y.S., S.R.P., A.S.E., J.H.S.) and the Taylor Family Institute for Innovative Psychiatric Research (G.A., A.S.E., J.H.S.), Washington University School of Medicine, St. Louis, Missouri
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Leirão IP, Zoccal DB, Gargaglioni LH, da Silva GSF. Differential modulation of active expiration during hypercapnia by the medullary raphe in unanesthetized rats. Pflugers Arch 2020; 472:1563-1576. [PMID: 32914212 DOI: 10.1007/s00424-020-02455-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 07/30/2020] [Accepted: 08/27/2020] [Indexed: 11/26/2022]
Abstract
Active expiration represents an important mechanism to improve ventilation in conditions of augmented ventilatory demand, such as hypercapnia. While a rostral ventromedullary region, the parafacial respiratory group (pFRG), has been identified as a conditional expiratory oscillator, little is known about how central chemosensitive sites contribute to modulate active expiration under hypercapnia. In this study, we investigated the influence of the medullary raphe in the emergence of phasic expiratory abdominal activity during hypercapnia in unanesthetized adult male rats, in a state-dependent manner. To do so, reverse microdialysis of muscimol (GABAA receptor agonist, 1 mM) or 8-OH-DPAT (5-HT1A agonist, 1 mM) was applied in the MR during sleep and wakefulness periods, both in normocapnic (room air) and hypercapnic conditions (7% CO2). Electromyography (EMG) of diaphragm and abdominal muscles was performed to measure inspiratory and expiratory motor outputs. We found that active expiration did not occur in room air exposure during wakefulness or sleep. However, hypercapnia did recruit active expiration, and differential effects were observed with the drug dialyses in the medullary raphe. Muscimol increased the diaphragm inspiratory motor output and also increased the amplitude and frequency of abdominal expiratory rhythmic activity during hypercapnia in wakefulness periods. On the other hand, the microdialysis of 8-OH-DPAT attenuated hypercapnia-induced active expiration in a state-dependent manner. Our data suggest that the medullary raphe can either inhibit or potentiate respiratory motor activity during hypercapnia, and the balance of these inhibitory or excitatory outputs may determine the expression of active expiration.
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Affiliation(s)
- Isabela P Leirão
- Department of Physiology and Pathology, School of Dentistry of Araraquara (FOAR), São Paulo State University (UNESP), Araraquara, SP, Brazil
| | - Daniel B Zoccal
- Department of Physiology and Pathology, School of Dentistry of Araraquara (FOAR), São Paulo State University (UNESP), Araraquara, SP, Brazil
| | - Luciane H Gargaglioni
- Department of Animal Morphology and Physiology, College of Agricultural and Veterinary Sciences, São Paulo State University (FCAV-UNESP), Jaboticabal, SP, Brazil
| | - Glauber S F da Silva
- Department of Physiology and Biophysics. Institute of Biological Sciences, Federal University of Minas Gerais (ICB/UFMG), Belo Horizonte, MG, Brazil.
- Departamento de Fisiologia e Biofísica, ICB/UFMG, Avenida Presidente Antônio Carlos, 6627, Campus UFMG, Belo Horizonte, MG, 31270-901, Brazil.
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35
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Kupka T, Broda MA, Wieczorek PP. What is the form of muscimol from fly agaric mushroom (Amanita muscaria) in water? An insight from NMR experiment supported by molecular modeling. Magn Reson Chem 2020; 58:584-593. [PMID: 31912552 DOI: 10.1002/mrc.4990] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 12/30/2019] [Accepted: 01/02/2020] [Indexed: 06/10/2023]
Abstract
The biologically active alkaloid muscimol is present in fly agaric mushroom (Amanita muscaria), and its structure and action is related to human neurotransmitter γ -aminobutyric acid (GABA). The current study reports on determination of muscimol form present in water solution using multinuclear 1 H and 13 C nuclear magnetic resonance (NMR) experiments supported by density functional theory molecular modeling. The structures of three forms of free muscimol molecule both in the gas phase and in the presence of water solvent, modeled by polarized continuous model, and nuclear magnetic isotropic shieldings, the corresponding chemical shifts, and indirect spin-spin coupling constants were calculated. Several J-couplings observed in proton and carbon NMR spectra, not available before, are reported. The obtained experimental spectra, supported by theoretical calculations, favor the zwitterion form of muscimol in water. This structure differs from NH isomer, previously determined in dimethyl sulfoxide (DMSO) solution. In addition, positions of signals C3 and C5 are reversed in both solvents.
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Affiliation(s)
- Teobald Kupka
- Faculty of Chemistry, University of Opole, Opole, Poland
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36
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Chen Y, Kang N, Gu J, Chu B, Luo L, An Y, Yang F, Cao J, Zhang J. Inactivation of endopeduncular nucleus impaired fear conditioning and hippocampal synaptic plasticity in rats. Neurobiol Learn Mem 2020; 173:107224. [PMID: 32246991 DOI: 10.1016/j.nlm.2020.107224] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 03/11/2020] [Accepted: 03/27/2020] [Indexed: 11/17/2022]
Abstract
The internal globus pallidus (GPi) is one part of basal ganglion nucleuses which play fundamental role in motor function. Recent studies indicated that GPi could modulate emotional processing and learning, but the possible mechanism remains still unknown. In this study, the effects of endopeduncular nucleus (EP, a rodent homolog of GPi) on fear conditioning were tested in rats. GABAA receptor agonist muscimol was bilaterally delivered into the EP 15 min before or immediately after fear conditioning in rats. We found that EP inactivation impaired the acquisition but not consolidation of fear memory in rats. Furthermore, the long-term potentiation (LTP) in hippocampal CA1 area was impaired, and the learning related phosphorylation of α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor (AMPAR) subunit 1 (GluA1) at the Ser845 site in hippocampus was decreased in muscimol treated group. These results demonstrated that dysfunction of EP impaired hippocampal dependent learning and memory in rats.
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Affiliation(s)
- Yanmei Chen
- Department of Basic Medicine, Medical School, Kunming University of Science and Technology, Kunming, Yunnan 650550, China
| | - Na Kang
- Department of Basic Medicine, Medical School, Kunming University of Science and Technology, Kunming, Yunnan 650550, China
| | - Jingsheng Gu
- Department of Basic Medicine, Medical School, Kunming University of Science and Technology, Kunming, Yunnan 650550, China
| | - Boling Chu
- Department of Basic Medicine, Medical School, Kunming University of Science and Technology, Kunming, Yunnan 650550, China
| | - Lilu Luo
- Department of Basic Medicine, Medical School, Kunming University of Science and Technology, Kunming, Yunnan 650550, China
| | - Yingjie An
- Department of Basic Medicine, Medical School, Kunming University of Science and Technology, Kunming, Yunnan 650550, China
| | - Fengyuan Yang
- School of Life Science and Medicine, Dalian University of Technology, China
| | - Jun Cao
- Laboratory of Ecology and Evolutionary Biology, State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan University, Kunming, Yunnan 650091, China
| | - Jichuan Zhang
- Department of Basic Medicine, Medical School, Kunming University of Science and Technology, Kunming, Yunnan 650550, China.
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37
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Abstract
Neocortical sensory areas are thought to act as distribution hubs, transmitting information about the external environment to downstream areas. Within primary visual cortex, various populations of pyramidal neurons (PNs) send axonal projections to distinct targets, suggesting multiple cellular networks may be independently engaged during behavior. We investigated whether PN subpopulations differentially support visual detection by training mice on a novel eyeblink conditioning task. Applying 2-photon calcium imaging and optogenetic manipulation of anatomically defined PNs, we show that layer 5 corticopontine neurons strongly encode sensory and motor task information and are selectively necessary for performance. Our findings support a model in which target-specific cortical subnetworks form the basis for adaptive behavior by directing relevant information to distinct brain areas. Overall, this work highlights the potential for neurons to form physically interspersed but functionally segregated networks capable of parallel, independent control of perception and behavior.
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Affiliation(s)
- Lan Tang
- Department of Neuroscience, Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Michael J Higley
- Department of Neuroscience, Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT 06510, USA.
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38
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Kreutzmann JC, Jovanovic T, Fendt M. Infralimbic cortex activity is required for the expression but not the acquisition of conditioned safety. Psychopharmacology (Berl) 2020; 237:2161-2172. [PMID: 32363439 PMCID: PMC7306044 DOI: 10.1007/s00213-020-05527-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 04/13/2020] [Indexed: 02/06/2023]
Abstract
The ability to discriminate between danger and safety is crucial for survival across species. Whereas danger signals predict the onset of a potentially threatening event, safety signals indicate the non-occurrence of an aversive event, thereby reducing fear and stress responses. While the neural basis of conditioned safety remains to be elucidated, fear extinction studies provide evidence that the infralimbic cortex (IL) modulates fear inhibition. In the current study, the IL was temporarily inactivated with local muscimol injections in male and female rats. The effect of IL inactivation on the acquisition and expression of conditioned safety was investigated utilizing the startle response. Temporary inactivation of the IL prior to conditioning did not affect the acquisition of conditioned safety, whereas IL inactivation during the expression test completely blocked the expression of conditioned safety in male and female rats. Inactivation of the neighboring prelimbic (PL) cortex during the expression test did not affect the expression of safety memory. Our findings suggest that the IL is a critical brain region for the expression of safety memory. Because patients suffering from anxiety disorders are often unable to make use of safety cues to inhibit fear, the present findings are of clinical relevance and could potentially contribute to therapy optimization of anxiety-related psychiatric disorders.
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Affiliation(s)
- Judith C Kreutzmann
- Medical Faculty, Institute for Pharmacology & Toxicology, Otto-von-Guericke University Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Germany.
- Leibniz Institute for Neurobiology, Magdeburg, Germany.
| | - Tanja Jovanovic
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University Detroit, Detroit, MI, USA
| | - Markus Fendt
- Medical Faculty, Institute for Pharmacology & Toxicology, Otto-von-Guericke University Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Germany
- Center for Behavioral Brain Sciences, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
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39
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Long Y, Tyerman SD, Gilliham M. Cytosolic GABA inhibits anion transport by wheat ALMT1. New Phytol 2020; 225:671-678. [PMID: 31591723 DOI: 10.1111/nph.16238] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 09/29/2019] [Indexed: 05/22/2023]
Abstract
Anion transport by aluminium-activated malate transporter (ALMT) proteins is negatively regulated by gamma-aminobutyric acid (GABA), which increases in concentration during stress. Here, the interaction between GABA and wheat (Triticum aestivum, Ta) TaALMT1 heterologously-expressed in Xenopus laevis oocytes was investigated. GABA inhibited anion transport by TaALMT1 in membrane patches from the cytosolic, not extracellular membrane face, via a reduction in open probability (NPopen ), not an inhibition of channel current magnitude. TaALMT1 currents in patches frequently exhibited rundown with complete removal of cytosolic factors, but were partially sustained by protein kinase C dependent phosphorylation. When applied to whole oocytes a GABA-analogue-BODIPY conjugate inhibited TaALMT1 anion currents from the cytoplasmic face only, whereas free GABA inhibited from both the inside and outside consistent with GABA traversing the TaALMT1 pore then acting from the inside. We propose GABA does not competitively inhibit ALMT conductance through the same pore but rather leads to an allosteric effect, reducing anion channel opening frequency. Across plants GABA is a conserved regulator of anion transport via ALMTs - a family with numerous physiological roles beyond Al3+ tolerance. Our data suggests that a GABA-ALMT interaction from the cytosolic face has the potential to form part of a novel plant signalling pathway.
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Affiliation(s)
- Yu Long
- Australian Research Council Centre of Excellence in Plant Energy Biology, Waite Research Precinct, University of Adelaide, Glen Osmond, SA, 5064, Australia
- School of Agriculture, Food and Wine, Waite Research Institute, Waite Research Precinct, University of Adelaide, Glen Osmond, SA, 5064, Australia
| | - Stephen D Tyerman
- Australian Research Council Centre of Excellence in Plant Energy Biology, Waite Research Precinct, University of Adelaide, Glen Osmond, SA, 5064, Australia
- School of Agriculture, Food and Wine, Waite Research Institute, Waite Research Precinct, University of Adelaide, Glen Osmond, SA, 5064, Australia
| | - Matthew Gilliham
- Australian Research Council Centre of Excellence in Plant Energy Biology, Waite Research Precinct, University of Adelaide, Glen Osmond, SA, 5064, Australia
- School of Agriculture, Food and Wine, Waite Research Institute, Waite Research Precinct, University of Adelaide, Glen Osmond, SA, 5064, Australia
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Han Y, Bruls R, Soyman E, Thomas RM, Pentaraki V, Jelinek N, Heinemans M, Bassez I, Verschooren S, Pruis I, Van Lierde T, Carrillo N, Gazzola V, Carrillo M, Keysers C. Bidirectional cingulate-dependent danger information transfer across rats. PLoS Biol 2019; 17:e3000524. [PMID: 31805039 PMCID: PMC6894752 DOI: 10.1371/journal.pbio.3000524] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Accepted: 10/16/2019] [Indexed: 12/11/2022] Open
Abstract
Social transmission of freezing behavior has been conceived of as a one-way phenomenon in which an observer "catches" the fear of another. Here, we use a paradigm in which an observer rat witnesses another rat receiving electroshocks. Bayesian model comparison and Granger causality show that rats exchange information about danger in both directions: how the observer reacts to the demonstrator's distress also influences how the demonstrator responds to the danger. This was true to a similar extent across highly familiar and entirely unfamiliar rats but is stronger in animals preexposed to shocks. Injecting muscimol in the anterior cingulate of observers reduced freezing in the observers and in the demonstrators receiving the shocks. Using simulations, we support the notion that the coupling of freezing across rats could be selected for to more efficiently detect dangers in a group, in a way similar to cross-species eavesdropping.
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Affiliation(s)
- Yingying Han
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands
| | - Rune Bruls
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands
| | - Efe Soyman
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands
| | - Rajat Mani Thomas
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands
| | - Vasiliki Pentaraki
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands
- A student of Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Naomi Jelinek
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands
- A student of the Department of Applied Life Sciences, FH Campus Wien, Wien, Austria
| | - Mirjam Heinemans
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands
- Department of Psychology, Faculty of Social and Behavioural Sciences, University of Amsterdam (UvA), Amsterdam, the Netherlands
| | - Iege Bassez
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands
- A student of the Faculty of Psychology and Educational Sciences, Ghent University, Ghent, Belgium
| | - Sam Verschooren
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands
- A student of the Faculty of Psychology and Educational Sciences, Ghent University, Ghent, Belgium
| | - Illanah Pruis
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands
- A student of Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Thijs Van Lierde
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands
- A student of the Faculty of Psychology and Educational Sciences, Ghent University, Ghent, Belgium
| | - Nathaly Carrillo
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands
| | - Valeria Gazzola
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands
- Department of Psychology, Faculty of Social and Behavioural Sciences, University of Amsterdam (UvA), Amsterdam, the Netherlands
| | - Maria Carrillo
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands
| | - Christian Keysers
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, the Netherlands
- Department of Psychology, Faculty of Social and Behavioural Sciences, University of Amsterdam (UvA), Amsterdam, the Netherlands
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41
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Glover EJ, Starr EM, Chao Y, Jhou TC, Chandler LJ. Inhibition of the rostromedial tegmental nucleus reverses alcohol withdrawal-induced anxiety-like behavior. Neuropsychopharmacology 2019; 44:1896-1905. [PMID: 31060041 PMCID: PMC6785010 DOI: 10.1038/s41386-019-0406-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Revised: 04/24/2019] [Accepted: 04/26/2019] [Indexed: 12/13/2022]
Abstract
Acute withdrawal from alcohol is associated with a number of unpleasant symptoms that play an important role in preventing recovery and long-term abstinence. Considerable research has focused on the role that neuropeptide systems and the amygdala play in mediating affective symptoms of acute withdrawal, but promising preclinical findings have not translated successfully into the clinic. The rostromedial tegmental nucleus (RMTg) has been implicated in both fear and anxiety. In addition, RMTg neurons exert inhibitory control over midbrain dopamine neurons, the activity of which are suppressed during acute withdrawal. Thus, we hypothesized that the RMTg may play a role in mediating symptoms of acute withdrawal. Using a chronic ethanol vapor exposure paradigm that renders rats physically dependent on ethanol, we observed significant withdrawal-induced enhancement of cFos expression in the RMTg. This was accompanied by a significant increase in somatic symptoms and a decrease in reward sensitivity as measured by intracranial self-stimulation (ICSS). Both measures followed a similar time course to RMTg cFos expression with peak symptom severity occurring 12 h following cessation of ethanol exposure. Heightened anxiety-like behavior was also observed in withdrawn rats at this same time point. RMTg inhibition had no effect on somatic signs of withdrawal or withdrawal-induced changes in reward sensitivity, but significantly attenuated withdrawal-induced anxiety-like behavior. Together, these data demonstrate that the RMTg plays a distinct role in the negative affective state associated with acute withdrawal and may therefore be critically involved in the neurobiological mechanisms that promote relapse during early stages of recovery.
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Affiliation(s)
- Elizabeth J Glover
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, 29425, USA.
- Center for Drug & Alcohol Programs, Medical University of South Carolina, Charleston, SC, 29425, USA.
| | - E Margaret Starr
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, 29425, USA
- Center for Drug & Alcohol Programs, Medical University of South Carolina, Charleston, SC, 29425, USA
| | - Ying Chao
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, 29425, USA
| | - Thomas C Jhou
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, 29425, USA
| | - L Judson Chandler
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, 29425, USA
- Center for Drug & Alcohol Programs, Medical University of South Carolina, Charleston, SC, 29425, USA
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Blouin AM, Pisupati S, Hoffer CG, Hafenbreidel M, Jamieson SE, Rumbaugh G, Miller CA. Social stress-potentiated methamphetamine seeking. Addict Biol 2019; 24:958-968. [PMID: 30105771 PMCID: PMC6375809 DOI: 10.1111/adb.12666] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 05/17/2018] [Accepted: 07/09/2018] [Indexed: 12/12/2022]
Abstract
Human studies of substance use disorder show that psychological stress and drug availability interact following rehabilitation, contributing to the high relapse potential. Social stressors trigger particularly strong motivation for drug, but how this affects neuronal function to increase relapse is unknown. Animal models, which allow for the dissection of neural mechanisms, primarily utilize physical stressors to trigger relapse. To recapitulate psychosocial post-rehabilitation challenges in animals, we developed a model of social stress-potentiated methamphetamine (METH) seeking. Rats receive a single social defeat (SD) session after completion of self-administration and extinction of lever pressing. While a reminder of the SD was insufficient to reinstate METH seeking on its own, rats that received a reminder of SD followed by a METH-priming injection displayed potentiated reinstatement over METH-priming alone. Examination of neuronal activation patterns of the METH-primed reinstatement session identified c-Fos-immunoreactivity in the basolateral amygdala (BLA) as correlated with SD score, a measure of defeat latency. Rapidly defeated rats showed potentiated METH-primed reinstatement and elevated BLA c-Fos compared with controls. Conversely, rats that were undefeated during the social stress did not show potentiated METH-primed reinstatement or elevated BLA c-Fos. Interestingly, inactivation of the BLA with baclofen/muscimol prior to the stress reminder and METH-priming generated a potentiation of METH seeking in the undefeated rats, suggesting the BLA may mediate resilience to the stressor. This model provides a tool for the further dissection of neural mechanisms mediating social stress-potentiated relapse and for the development of relapse-reducing therapeutics.
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Affiliation(s)
- Ashley M. Blouin
- Department of Molecular Medicine
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458
| | - Swathi Pisupati
- Department of Molecular Medicine
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458
| | - Colton G. Hoffer
- Department of Molecular Medicine
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458
| | - Madalyn Hafenbreidel
- Department of Molecular Medicine
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458
| | - Sarah E. Jamieson
- Department of Molecular Medicine
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458
| | - Gavin Rumbaugh
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458
| | - Courtney A. Miller
- Department of Molecular Medicine
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL 33458
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Kondeva-Burdina M, Voynova M, Shkondrov A, Aluani D, Tzankova V, Krasteva I. Effects of Amanita muscaria extract on different in vitro neurotoxicity models at sub-cellular and cellular levels. Food Chem Toxicol 2019; 132:110687. [PMID: 31325463 DOI: 10.1016/j.fct.2019.110687] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Revised: 07/15/2019] [Accepted: 07/16/2019] [Indexed: 11/19/2022]
Abstract
Muscimol is the main compound found in Amanita muscaria. Several studies have proven that muscimol has suppressive effects on essential tremor, without impairing speech and coordination. The effects of muscimol in Parkinson-affected patients is also described in a number of studies. These studies describe the free radical scavenging and antioxidant activity of the mushroom extract. We have evaluated the possible neuroprotective effects of a standardized extract from A. muscaria, containing high amounts of muscimol, on different models of neurotoxicity in rat brain microsomes, mitochondria, synaptosomes as well as on neuroblastoma cell line SH-SY5Y. The possible inhibitory effect on human recombinant monoaminoxidase-B (hMAOB) enzyme was also studied. The extract revealed statistically significant neuroprotective effects on the in vitro neurotoxicity models and no inhibitory activity on hMAOB.
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Affiliation(s)
- Magdalena Kondeva-Burdina
- Laboratory of Drug Metabolism and Drug Toxicity, Department of Pharmacology, Pharmacotherapy and Toxicology, Faculty of Pharmacy, Medical University of Sofia, 2 Dunav St., 1000, Sofia, Bulgaria.
| | - Maria Voynova
- Laboratory of Drug Metabolism and Drug Toxicity, Department of Pharmacology, Pharmacotherapy and Toxicology, Faculty of Pharmacy, Medical University of Sofia, 2 Dunav St., 1000, Sofia, Bulgaria
| | - Aleksandar Shkondrov
- Department of Pharmacognosy, Faculty of Pharmacy, Medical University of Sofia, 2 Dunav St., 1000, Sofia, Bulgaria
| | - Denitsa Aluani
- Laboratory of Drug Metabolism and Drug Toxicity, Department of Pharmacology, Pharmacotherapy and Toxicology, Faculty of Pharmacy, Medical University of Sofia, 2 Dunav St., 1000, Sofia, Bulgaria
| | - Virginia Tzankova
- Laboratory of Drug Metabolism and Drug Toxicity, Department of Pharmacology, Pharmacotherapy and Toxicology, Faculty of Pharmacy, Medical University of Sofia, 2 Dunav St., 1000, Sofia, Bulgaria
| | - Ilina Krasteva
- Department of Pharmacognosy, Faculty of Pharmacy, Medical University of Sofia, 2 Dunav St., 1000, Sofia, Bulgaria
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Zhu X, Yao Y, Li X, Dong J, Zhang A. Alteration of GABAergic signaling is associated with anxiety-like behavior in temporal lobe epilepsy mice. Prog Neuropsychopharmacol Biol Psychiatry 2019; 93:141-148. [PMID: 30951784 DOI: 10.1016/j.pnpbp.2019.03.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Revised: 03/20/2019] [Accepted: 03/29/2019] [Indexed: 12/18/2022]
Abstract
Temporal lobe epilepsy (TLE), which is one of the most common neurological diseases, is accompanied by a high incidence of psychiatric disorders. Among these psychiatric disorders, anxiety is one of the major psychiatric comorbidities in epilepsy patients. However, anxiety in epilepsy patients often remains unrecognized and untreated. It is believed that the inhibitory networks of γ-aminobutyric acid (GABA) neurotransmission play pivotal roles in the modulation of emotion and mood responses in both physiological and pathological conditions. The impairment of neurotransmission mediated by GABAergic signaling is related to the pathophysiology of anxiety. However, it remains unclear whether and how GABAergic signaling modulates anxiety responses in the context of an epileptic brain. In the present study, we sought to determine the role of inhibitory networks of GABAergic signaling in the anxiety-like behavior of epileptic mice. Our results show epileptic mice exhibited increased anxiety-like behavior, and this increased anxiety-like behavior was accompanied by a decrease in GABAergic interneurons and an increase in GABA type A receptor (GABAAR) β3 subunit (GABRB3) expression in the hippocampus. Furthermore, the activation of GABAARs produced an anxiolytic-like effect, while the inhibition of GABAARs elicited an anxiogenic-like effect in the epileptic mice, suggesting that the alteration of GABAergic signaling is associated with anxiety-like behavior in epileptic mice. Thus, targeting GABAergic signaling in the epileptic brain may provide an effective anxiolytic treatment in epilepsy patients.
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Affiliation(s)
- Xinjian Zhu
- Department of Pharmacology, Medical School of Southeast University, Nanjing, China.
| | - Yuanyuan Yao
- Department of Pharmacology, Medical School of Southeast University, Nanjing, China
| | - Xiaolin Li
- Department of Geriatrics, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Jingde Dong
- Department of Geriatric Neurology, Nanjing Brain Hospital Affiliated with Nanjing Medical University, Nanjing, China
| | - Aifeng Zhang
- Department of Pathology, Medical School of Southeast University, Nanjing, China
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Setogawa T, Mizuhiki T, Matsumoto N, Akizawa F, Kuboki R, Richmond BJ, Shidara M. Neurons in the monkey orbitofrontal cortex mediate reward value computation and decision-making. Commun Biol 2019; 2:126. [PMID: 30963114 PMCID: PMC6451015 DOI: 10.1038/s42003-019-0363-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 03/01/2019] [Indexed: 11/28/2022] Open
Abstract
Choice reflects the values of available alternatives; more valuable options are chosen more often than less valuable ones. Here we studied whether neuronal responses in orbitofrontal cortex (OFC) reflect the value difference between options, and whether there is a causal link between OFC neuronal activity and choice. Using a decision-making task where two visual stimuli were presented sequentially, each signifying a value, we showed that when the second stimulus appears many neurons encode the value difference between alternatives. Later when the choice occurs, that difference signal disappears and a signal indicating the chosen value emerges. Pharmacological inactivation of OFC neurons coding for choice-related values increases the monkey's latency to make a choice and the likelihood that it will choose the less valuable alternative, when the value difference is small. Thus, OFC neurons code for value information that could be used to directly influence choice.
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Affiliation(s)
- Tsuyoshi Setogawa
- Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 Japan
- Department of Health and Human Services, Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892-4415 USA
| | - Takashi Mizuhiki
- Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 Japan
- Doctoral Program in Kansei, Behavioral and Brain Science, Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 Japan
| | - Narihisa Matsumoto
- Human Informatics Research Institute, AIST, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 Japan
| | - Fumika Akizawa
- Doctoral Program in Kansei, Behavioral and Brain Science, Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 Japan
| | - Ryosuke Kuboki
- Doctoral Program in Kansei, Behavioral and Brain Science, Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 Japan
| | - Barry J. Richmond
- Department of Health and Human Services, Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892-4415 USA
| | - Munetaka Shidara
- Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 Japan
- Doctoral Program in Kansei, Behavioral and Brain Science, Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 Japan
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Burhans LB, Schreurs BG. Inactivation of the interpositus nucleus blocks the acquisition of conditioned responses and timing changes in conditioning-specific reflex modification of the rabbit eyeblink response. Neurobiol Learn Mem 2018; 155:143-156. [PMID: 30053576 PMCID: PMC6731038 DOI: 10.1016/j.nlm.2018.07.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 07/20/2018] [Accepted: 07/23/2018] [Indexed: 01/08/2023]
Abstract
Conditioning-specific reflex modification (CRM) of the rabbit eyeblink response is an associative phenomenon characterized by increases in the frequency, size, and peak latency of the reflexive unconditioned eyeblink response (UR) when the periorbital shock unconditioned stimulus (US) is presented alone following conditioning, particularly to lower intensity USs that produced minimal responding prior to conditioning. Previous work has shown that CRM shares many commonalities with the conditioned eyeblink response (CR) including a similar response topography, suggesting the two may share similar neural substrates. The following study examined the hypothesis that the interpositus nucleus (IP) of the cerebellum, an essential part of the neural circuitry of eyeblink conditioning, is also required for the acquisition of CRM. Tests for CRM occurred following delay conditioning under muscimol inactivation of the IP and also after additional conditioning without IP inactivation. Results showed that IP inactivation blocked acquisition of CRs and the timing aspect of CRM but did not prevent increases in UR amplitude and area. Following the cessation of inactivation, CRs and CRM latency changes developed similarly to controls with intact IP functioning, but with some indication that CRs may have been facilitated in muscimol rabbits. In conclusion, CRM timing and CRs both likely require the development of plasticity in the IP, but other associative UR changes may involve non-cerebellar structures interacting with the eyeblink conditioning circuitry, a strong candidate being the amygdala, which is also likely involved in the facilitation of conditioning. Other candidates worth consideration include the cerebellar cortex, prefrontal and motor cortices.
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Affiliation(s)
- Lauren B Burhans
- Rockefeller Neuroscience Institute and Department of Physiology and Pharmacology, West Virginia University, Morgantown, WV, USA.
| | - Bernard G Schreurs
- Rockefeller Neuroscience Institute and Department of Physiology and Pharmacology, West Virginia University, Morgantown, WV, USA
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Abstract
The role of GABAergic inhibition in the regulation of activity of the parafacial respiratory group was studied on narcotized mature rats. Microinjections of GABAA agonist muscimol into the parafacial respiratory group inhibited external respiration and bioelectrical activity of the diaphragmatic muscle resulting in diminished tidal volume and decreased respiration rate accompanied by prolonged inspiration, expiration, and intervals between the inspiratory bursts in the phrenic electromyogram. In contrast, microinjections of GABAA antagonist bicuculline into this group stimulated respiration and markedly increased its volumetric parameters. In addition, blockade of GABAA receptors affected the expiratory phase and interburst intervals in the phrenic electromyogram, but produced no effect on respiration rate. These findings attested to contribution of GABAA-mediated inhibition into the performance of parafacial respiratory group. The study revealed different roles of GABAA receptors in modulation of the mechanisms of respiration rate control in mature rats and formation of inspiratory motor outputs originating from the parafacial respiratory group.
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Affiliation(s)
- O A Vedyasova
- Department of Human and Animal Physiology, S. P. Korolev Samara National Research University, Samara, Russia.
| | - T E Kovaleva
- Department of Human and Animal Physiology, S. P. Korolev Samara National Research University, Samara, Russia
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Sugiyama A, Yamada M, Saitoh A, Nagase H, Oka JI, Yamada M. Administration of a delta opioid receptor agonist KNT-127 to the basolateral amygdala has robust anxiolytic-like effects in rats. Psychopharmacology (Berl) 2018; 235:2947-2955. [PMID: 30066134 DOI: 10.1007/s00213-018-4984-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 07/23/2018] [Indexed: 12/16/2022]
Abstract
RATIONALE We previously reported that systemic administration of a selective delta opioid receptor (DOP) agonist, KNT-127, produced potent anxiolytic-like effects in rats. Interestingly, DOPs are highly distributed in the basolateral region of the amygdala (BLA). OBJECTIVES In this study, we investigated the effect of intra-BLA administration of KNT-127 on anxiety-like behaviors in rats. METHODS AND RESULTS In the elevated plus maze test, bilateral injection of KNT-127 into the BLA significantly and dose-dependently increased time spent in the open arms. The magnitude of KNT-127 (0.08 μg/0.2 μl)-induced anxiolytic-like effects was similar to muscimol (0.1 μg/0.2 μl), which is a selective agonist for the gamma amino butyric acid type A receptors. Further, anxiolytic-like effects of KNT-127 were abolished by pretreatment with naltrindole, a selective DOP antagonist, suggesting that KNT-127-induced anxiolytic-like effects are mediated by DOPs. These anxiolytic-like effects were confirmed using another innate anxiety model, the open field test. Interestingly, intra-BLA administration of KNT-127 also induced anxiolytic-like effects in the contextual fear conditioning test. Moreover, these effects were also abolished by naltrindole pretreatment. Finally, we demonstrated that intra-BLA administration of KNT-127 facilitates extinction learning of contextual fear in conditioned rats. CONCLUSIONS Altogether, our findings clearly demonstrate that intra-BLA administration of KNT-127 in rats has robust anxiolytic-like effects not only in innate anxiety-like behavioral tests but also in the contextual fear conditioning test.
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Affiliation(s)
- Azusa Sugiyama
- Department of Neuropsychopharmacology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, 187-8553, Japan
- Laboratory of Pharmacology, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Chiba, 278-8510, Japan
| | - Misa Yamada
- Department of Neuropsychopharmacology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, 187-8553, Japan
| | - Akiyoshi Saitoh
- Department of Neuropsychopharmacology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, 187-8553, Japan
| | - Hiroshi Nagase
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Ibaraki, 305-8575, Japan
| | - Jun-Ichiro Oka
- Laboratory of Pharmacology, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Chiba, 278-8510, Japan
| | - Mitsuhiko Yamada
- Department of Neuropsychopharmacology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, 187-8553, Japan.
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Bollimunta A, Bogadhi AR, Krauzlis RJ. Comparing frontal eye field and superior colliculus contributions to covert spatial attention. Nat Commun 2018; 9:3553. [PMID: 30177726 PMCID: PMC6120922 DOI: 10.1038/s41467-018-06042-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 07/31/2018] [Indexed: 02/07/2023] Open
Abstract
The causal roles of the frontal eye fields (FEF) and superior colliculus (SC) in spatial selective attention have not been directly compared. Reversible inactivation is an established method for testing causality but comparing results between FEF and SC is complicated by differences in size and morphology of the two brain regions. Here we exploited the fact that inactivation of FEF and SC also changes the metrics of saccadic eye movements, providing an independent benchmark for the strength of the causal manipulation. Using monkeys trained to covertly perform a visual motion-change detection task, we found that inactivation of either FEF or SC could cause deficits in attention task performance. However, SC-induced attention deficits were found with saccade changes half the size needed to get FEF-induced attention deficits. Thus, performance in visual attention tasks is vulnerable to loss of signals from either structure, but suppression of SC activity has a more devastating effect.
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Affiliation(s)
- Anil Bollimunta
- Laboratory of Sensorimotor Research, National Eye Institute, Bethesda, MD, 20892, USA
| | - Amarender R Bogadhi
- Laboratory of Sensorimotor Research, National Eye Institute, Bethesda, MD, 20892, USA
| | - Richard J Krauzlis
- Laboratory of Sensorimotor Research, National Eye Institute, Bethesda, MD, 20892, USA.
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Chang YY, Gong XW, Gong HQ, Liang PJ, Zhang PM, Lu QC. GABA A Receptor Activity Suppresses the Transition from Inter-ictal to Ictal Epileptiform Discharges in Juvenile Mouse Hippocampus. Neurosci Bull 2018; 34:1007-1016. [PMID: 30128691 DOI: 10.1007/s12264-018-0273-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 05/31/2018] [Indexed: 12/12/2022] Open
Abstract
Exploring the transition from inter-ictal to ictal epileptiform discharges (IDs) and how GABAA receptor-mediated action affects the onset of IDs will enrich our understanding of epileptogenesis and epilepsy treatment. We used Mg2+-free artificial cerebrospinal fluid (ACSF) to induce epileptiform discharges in juvenile mouse hippocampal slices and used a micro-electrode array to record the discharges. After the slices were exposed to Mg2+-free ACSF for 10 min-20 min, synchronous recurrent seizure-like events were recorded across the slices, and each event evolved from inter-ictal epileptiform discharges (IIDs) to pre-ictal epileptiform discharges (PIDs), and then to IDs. During the transition from IIDs to PIDs, the duration of discharges increased and the inter-discharge interval decreased. After adding 3 μmol/L of the GABAA receptor agonist muscimol, PIDs and IDs disappeared, and IIDs remained. Further, the application of 10 μmol/L muscimol abolished all the epileptiform discharges. When the GABAA receptor antagonist bicuculline was applied at 10 μmol/L, IIDs and PIDs disappeared, and IDs remained at decreased intervals. These results indicated that there are dynamic changes in the hippocampal network preceding the onset of IDs, and GABAA receptor activity suppresses the transition from IIDs to IDs in juvenile mouse hippocampus.
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Affiliation(s)
- Yan-Yan Chang
- Department of Neurology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200127, China
| | - Xin-Wei Gong
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Hai-Qing Gong
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Pei-Ji Liang
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Pu-Ming Zhang
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Qin-Chi Lu
- Department of Neurology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200127, China.
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