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Potrebić MS, Pavković ŽZ, Srbovan MM, Ðmura GM, Pešić VT. Changes in the Behavior and Body Weight of Mature, Adult Male Wistar Han Rats after Reduced Social Grouping and Social Isolation. JOURNAL OF THE AMERICAN ASSOCIATION FOR LABORATORY ANIMAL SCIENCE : JAALAS 2022; 61:615-623. [PMID: 36328417 PMCID: PMC9732776 DOI: 10.30802/aalas-jaalas-22-000032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Changes in housing density, including individual housing, are commonly necessary in animal research. Obtaining reproducibility and translational validity in biomedical research requires an understanding of how animals adapt to changes in housing density. Existing literature mainly addresses acclimatization after transportation. We used a within-subject design to examine changes in behavior and weight gain of 4-mo-old male Wistar Han rats after reduction of their social group (RSG; due to removal of one rat from a cage containing 3 rats) and social isolation (SI; the removed rat) for the subsequent 2 wk. Changes in weight gain and in exploratory and center-avoidance behavior in an inescapable open arena (OA) were measured before (D0) and on days 7 and 14 (D7 and D14, respectively) after social change. The motor response to d-amphetamine (1.5 mg/kg), which stimulates behavioral arousal in response to novelty, was assessed at D14. Within-subject design revealed that RSG rats in OA had less locomotion at D7 but not more center-avoidance behavior and had returned to the D0 activity level at D14; SI rats in OA had consistently less locomotion and more center-avoidance behavior. Rearing behavior during OA exposure did not change in either group. However, SI rats showed more center-avoidance behavior in OA, greater weight gain, and less amphetamine-induced rearing at D14 as compared with RSG rats. These data indicate that after RSG, mature adult male rats require 2 wk to return to their baseline level of OA-related behavior, while after SI they gain weight and acquire maladaptive exploratory and center-avoidance behavior. The finding that SI produces maladaptive behavioral and physiologic alterations in adult male rats deserves attention because these changes could have confounding effects on research findings.
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Affiliation(s)
- Milica S Potrebić
- Department of Neurobiology, Institute for Biological Research Siniša Stanković – National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Željko Z Pavković
- Department of Neurobiology, Institute for Biological Research Siniša Stanković – National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Maja M Srbovan
- Department of Neurobiology, Institute for Biological Research Siniša Stanković – National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Goran M Ðmura
- Animal Facility, Institute for Biological Research Siniša Stanković – National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Vesna T Pešić
- Department of Neurobiology, Institute for Biological Research Siniša Stanković – National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia,,Corresponding author.
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Podgorac J, Sekulić S, Petković B, Stojadinović G, Martać L, Pešić V. The influence of continuous prenatal exposure to valproic acid on physical, nociceptive, emotional and psychomotor responses during adolescence in mice: Dose-related effects within sexes. Front Behav Neurosci 2022; 16:982811. [PMID: 36248030 PMCID: PMC9557044 DOI: 10.3389/fnbeh.2022.982811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 08/31/2022] [Indexed: 11/23/2022] Open
Abstract
Clinical findings show that the use of valproic acid (VPA) during pregnancy increases the risk of birth defects and autism spectrum disorder in offspring. Although there is a consensus that monitoring of potential long-term outcomes of VPA exposure is needed, especially in undiagnosed individuals, preclinical studies addressing this issue are rare. The present study examined the effects of continuous intrauterine exposure to a wide dose range of VPA (50, 100, 200, and 400 mg/kg/day) on the physical and behavioral response in peripubertal mice as a rodent model of adolescence. Body weight and the hot plate test [on postnatal days (PND) 25 and 32], the elevated plus-maze test (on PND35), and the open field test (on PND40) served to examine physical growth, the supraspinal reflex response to a painful thermal stimulus and conditional learning, anxiety-like/risk-assessment behavior, as well as novelty-induced psychomotor activity, respectively. VPA exposure produced the following responses: (i) a negative effect on body weight, except for the dose of 100 mg/kg/day in both sexes; (ii) an increase in the percentage of animals that responded to the thermal stimulus above the defined cut-off time interval and the response latency in both sexes; (iii) dose-specific changes within sexes in behavior provoked by a novel anxiogenic environment, i.e., in females less anxiety-like/risk-assessment behavior in response to the lowest exposure dose, and in males more pronounced anxiety-like/risk-assessment behavior after exposure to the highest dose and 100 mg/kg/day; (iv) dose-specific changes within sexes in novelty-induced psychomotor activity, i.e., in females a decrease in stereotypy-like activity along with an increase in rearing, and in males a decrease in stereotypy-like activity only. These findings show that continuous intrauterine exposure to VPA produces maladaptive functioning in different behavioral domains in adolescence and that the consequences are delicate to assess as they are dose-related within sexes.
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Affiliation(s)
- Jelena Podgorac
- Department of Neurophysiology, Institute for Biological Research “Siniša Stanković” – National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Slobodan Sekulić
- Faculty of Medicine Novi Sad, University of Novi Sad, Novi Sad, Serbia
- Department of Neurology, Clinical Center of Vojvodina, Novi Sad, Serbia
| | - Branka Petković
- Department of Neurophysiology, Institute for Biological Research “Siniša Stanković” – National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Gordana Stojadinović
- Department of Neurophysiology, Institute for Biological Research “Siniša Stanković” – National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Ljiljana Martać
- Department of Neurophysiology, Institute for Biological Research “Siniša Stanković” – National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Vesna Pešić
- Department of Neurobiology, Institute for Biological Research “Siniša Stanković” – National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
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Janz P, Nicolas MJ, Redondo RL, Valencia M.
GABA
B
R
activation partially normalizes acute
NMDAR
hypofunction oscillatory abnormalities but fails to rescue sensory processing deficits. J Neurochem 2022; 161:417-434. [DOI: 10.1111/jnc.15602] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 01/21/2022] [Accepted: 02/12/2022] [Indexed: 12/01/2022]
Affiliation(s)
- Philipp Janz
- Roche Pharma Research and Early Development, Neuroscience and Rare Diseases, Roche Innovation Center Basel, F. Hoffmann‐La Roche Ltd, Grenzacherstrasse 124, 4070 Basel Switzerland
| | - Maria Jesus Nicolas
- Universidad de Navarra, CIMA, Program of Neuroscience, 31080 Pamplona Spain
- IdiSNA Navarra Institute for Health Research, 31080 Pamplona Spain
| | - Roger L. Redondo
- Roche Pharma Research and Early Development, Neuroscience and Rare Diseases, Roche Innovation Center Basel, F. Hoffmann‐La Roche Ltd, Grenzacherstrasse 124, 4070 Basel Switzerland
| | - Miguel Valencia
- Universidad de Navarra, CIMA, Program of Neuroscience, 31080 Pamplona Spain
- IdiSNA Navarra Institute for Health Research, 31080 Pamplona Spain
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Goswami N, Aleem M, Manda K. Clinical relevance of chronic neuropathic pain phenotypes in mice: A comprehensive behavioral analysis. Behav Brain Res 2020; 400:113055. [PMID: 33290758 DOI: 10.1016/j.bbr.2020.113055] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 08/13/2020] [Accepted: 12/01/2020] [Indexed: 11/30/2022]
Abstract
Despite a large number of preclinical studies performed each year, the safe and effective therapeutic interventions for chronic pain are scant. Therefore, it appears that pre-clinical modeling requires a systematically organized behavioral test paradigm to quantify the response of animals for a specific pain state. The present study, therefore, conceptualized a test battery to evaluate the behavioral changes in mice following neuropathic pain. We employed sciatic nerve chronic constriction injury (CCI) in C57BL/6 J mice to model chronic pain state. Mice were monitored for thermal hyperalgesia and grip strength for 30 days. Subsequently, mice underwent a behavioral test battery consisting of the nociceptive threshold, the affective and cognitive functions and motor coordination, and strength. Our results showed that CCI mice are insensitive to thermal stimuli. However, nerve-injured mice showed significant changes in neuromuscular coordination, basal anxiety, and hedonic state. Such impaired neuromuscular coordination is indicative of disability rather than the actual pain phenotype. While using the digital gait analysis, our study revealed rationales for the insensitivity of CCI mice to thermal stimuli. Our results suggest that the predictive validity of the CCI model necessitates a comprehensive behavioral test battery to select the clinically relevant and measurable phenotype to quantify chronic neuropathic pain.
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Affiliation(s)
- Nidhi Goswami
- Division of Behavioral Neuroscience, Institute of Nuclear Medicine & Allied Sciences, Delhi, India
| | - Mohd Aleem
- Division of Behavioral Neuroscience, Institute of Nuclear Medicine & Allied Sciences, Delhi, India
| | - Kailash Manda
- Division of Behavioral Neuroscience, Institute of Nuclear Medicine & Allied Sciences, Delhi, India.
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Doly S, Shirvani H, Gäta G, Meye F, Emerit MB, Enslen H, Achour L, Pardo-Lopez L, Kwon YS, Armand V, Gardette R, Giros B, Gassmann M, Bettler B, Mameli M, Darmon M, Marullo S. GABAB receptor cell-surface export is controlled by an endoplasmic reticulum gatekeeper. Mol Psychiatry 2016; 21:480-90. [PMID: 26033241 PMCID: PMC4828513 DOI: 10.1038/mp.2015.72] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 04/24/2015] [Accepted: 04/28/2015] [Indexed: 12/20/2022]
Abstract
Endoplasmic reticulum (ER) release and cell-surface export of many G protein-coupled receptors (GPCRs) are tightly regulated. For gamma-aminobutyric acid (GABA)B receptors of GABA, the major mammalian inhibitory neurotransmitter, the ligand-binding GB1 subunit is maintained in the ER by unknown mechanisms in the absence of hetero-dimerization with the GB2 subunit. We report that GB1 retention is regulated by a specific gatekeeper, PRAF2. This ER resident transmembrane protein binds to GB1, preventing its progression in the biosynthetic pathway. GB1 release occurs upon competitive displacement from PRAF2 by GB2. PRAF2 concentration, relative to that of GB1 and GB2, tightly controls cell-surface receptor density and controls GABAB function in neurons. Experimental perturbation of PRAF2 levels in vivo caused marked hyperactivity disorders in mice. These data reveal an unanticipated major impact of specific ER gatekeepers on GPCR function and identify PRAF2 as a new molecular target with therapeutic potential for psychiatric and neurological diseases involving GABAB function.
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Affiliation(s)
- Stéphane Doly
- Institut Cochin
INSERMCentre National de la Recherche ScientifiqueUniversité Paris Descartes - Paris 5Institut National de la Recherche Agronomique (INRA)Université de Versailles Saint-Quentin-en-Yvelines22 Rue Méchain, 75014 Paris
| | - Hamasseh Shirvani
- Institut Cochin
INSERMCentre National de la Recherche ScientifiqueUniversité Paris Descartes - Paris 5Institut National de la Recherche Agronomique (INRA)Université de Versailles Saint-Quentin-en-Yvelines22 Rue Méchain, 75014 Paris
| | - Gabriel Gäta
- Institut Cochin
INSERMCentre National de la Recherche ScientifiqueUniversité Paris Descartes - Paris 5Institut National de la Recherche Agronomique (INRA)Université de Versailles Saint-Quentin-en-Yvelines22 Rue Méchain, 75014 Paris
| | - Frank Meye
- Institut du Fer à Moulin
Université Pierre et Marie Curie - Paris 6INSERM17 Rue du fer à moulin 75005 Paris
| | - Michel-Boris Emerit
- CPN, Centre de Psychiatrie et Neurosciences
INSERMUniversité Paris Descartes - Paris 5Groupe Hospitalier BrocaSite Broca - Sainte Anne 2 ter Rue d'Alésia75014 Paris
| | - Hervé Enslen
- Institut Cochin
INSERMCentre National de la Recherche ScientifiqueUniversité Paris Descartes - Paris 5Institut National de la Recherche Agronomique (INRA)Université de Versailles Saint-Quentin-en-Yvelines22 Rue Méchain, 75014 Paris
| | - Lamia Achour
- Institut Cochin
INSERMCentre National de la Recherche ScientifiqueUniversité Paris Descartes - Paris 5Institut National de la Recherche Agronomique (INRA)Université de Versailles Saint-Quentin-en-Yvelines22 Rue Méchain, 75014 Paris
| | - Liliana Pardo-Lopez
- Institut Cochin
INSERMCentre National de la Recherche ScientifiqueUniversité Paris Descartes - Paris 5Institut National de la Recherche Agronomique (INRA)Université de Versailles Saint-Quentin-en-Yvelines22 Rue Méchain, 75014 Paris
| | - Yang Seung Kwon
- CPN, Centre de Psychiatrie et Neurosciences
INSERMUniversité Paris Descartes - Paris 5Groupe Hospitalier BrocaSite Broca - Sainte Anne 2 ter Rue d'Alésia75014 Paris
| | - Vincent Armand
- CPN, Centre de Psychiatrie et Neurosciences
INSERMUniversité Paris Descartes - Paris 5Groupe Hospitalier BrocaSite Broca - Sainte Anne 2 ter Rue d'Alésia75014 Paris
| | - Robert Gardette
- CPN, Centre de Psychiatrie et Neurosciences
INSERMUniversité Paris Descartes - Paris 5Groupe Hospitalier BrocaSite Broca - Sainte Anne 2 ter Rue d'Alésia75014 Paris
| | - Bruno Giros
- Physiopathologie des Maladies du Système Nerveux Central
Université Pierre et Marie Curie - Paris 6INSERMCentre National de la Recherche ScientifiqueBâtiment B, 4ème étage, case courrier 37 9 Quai Saint Bernard 75252 Paris Cedex 05
- Service Psychiatrie
McGill University [Montréal]Institut Universitaire en Santé Mentale Douglas6875 Boulevard Lasalle, Montréal, QC H4H 1R2
| | - Martin Gassmann
- Department of Biomedicine
University of Basel Petersplatz 1, 4003 Basel
| | - Bernhard Bettler
- Department of Biomedicine
University of Basel Petersplatz 1, 4003 Basel
| | - Manuel Mameli
- Institut du Fer à Moulin
Université Pierre et Marie Curie - Paris 6INSERM17 Rue du fer à moulin 75005 Paris
| | - Michèle Darmon
- Institut Cochin
INSERMCentre National de la Recherche ScientifiqueUniversité Paris Descartes - Paris 5Institut National de la Recherche Agronomique (INRA)Université de Versailles Saint-Quentin-en-Yvelines22 Rue Méchain, 75014 Paris
| | - Stefano Marullo
- Institut Cochin
INSERMCentre National de la Recherche ScientifiqueUniversité Paris Descartes - Paris 5Institut National de la Recherche Agronomique (INRA)Université de Versailles Saint-Quentin-en-Yvelines22 Rue Méchain, 75014 Paris
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6
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Adolescent toluene inhalation in rats affects white matter maturation with the potential for recovery following abstinence. PLoS One 2012; 7:e44790. [PMID: 23028622 PMCID: PMC3445546 DOI: 10.1371/journal.pone.0044790] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Accepted: 08/13/2012] [Indexed: 12/16/2022] Open
Abstract
Inhalant misuse is common during adolescence, with ongoing chronic misuse associated with neurobiological and cognitive abnormalities. While human imaging studies consistently report white matter abnormalities among long-term inhalant users, longitudinal studies have been lacking with limited data available regarding the progressive nature of such abnormalities, including the potential for recovery following periods of sustained abstinence. We exposed adolescent male Wistar rats (postnatal day 27) to chronic intermittent inhaled toluene (3,000 ppm) for 1 hour/day, 3 times/week for 8 weeks to model abuse patterns observed in adolescent and young adult human users. This dosing regimen resulted in a significant retardation in weight gain during the exposure period (p<0.05). In parallel, we performed longitudinal magnetic resonance imaging (T₂-weighted) and diffusion tensor imaging prior to exposure, and after 4 and 8 weeks, to examine the integrity of white matter tracts, including the anterior commissure and corpus callosum. We also conducted imaging after 8 weeks of abstinence to assess for potential recovery. Chronic intermittent toluene exposure during adolescence and early adulthood resulted in white matter abnormalities, including a decrease in axial (p<0.05) and radial (p<0.05) diffusivity. These abnormalities appeared region-specific, occurring in the anterior commissure but not the corpus callosum and were not present until after at least 4 weeks of exposure. Toluene-induced effects on both body weight and white matter parameters recovered following abstinence. Behaviourally, we observed a progressive decrease in rearing activity following toluene exposure but no difference in motor function, suggesting cognitive function may be more sensitive to the effects of toluene. Furthermore, deficits in rearing were present by 4 weeks suggesting that toluene may affect behaviour prior to detectable white matter abnormalities. Consequently, exposure to inhalants that contain toluene during adolescence and early adulthood appear to differentially affect white matter maturation and behavioural outcomes, although recovery can occur following abstinence.
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Hayes DJ, Hoang J, Greenshaw AJ. The role of nucleus accumbens shell GABA receptors on ventral tegmental area intracranial self-stimulation and a potential role for the 5-HT(2C) receptor. J Psychopharmacol 2011; 25:1661-75. [PMID: 21169393 DOI: 10.1177/0269881110389212] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Brain γ-aminobutyric acid (GABA) and 5-hydroxytryptamine (5-HT)(2C) receptors are implicated in the neuronal regulation of reward- and aversion-related behaviour. Within the mesocorticolimbic pathways of the brain, relationships between GABA containing neurons and 5-HT(2C) receptor activity may be important in this context. The primary aim of this study was to investigate the role of NAc shell GABA receptors on ventral tegmental area intracranial self-stimulation (ICSS) and to examine the systemic effects of GABAergic ligands in this context. The second aim was to investigate the relationship between GABA receptor- and 5-HT(2C) receptor-related ICSS behaviour, using systemic administration of the selective agonist WAY 161503. Locomotor activity was assessed to compare the potential motor effects of drugs; feeding behaviour and intra-NAc injections of amphetamine (1.0 µg/side) were used as positive controls. When administered systemically the GABA(A) receptor agonist muscimol and antagonist picrotoxin did not selectively change ICSS reward thresholds, although the 5-HT(2C) receptor agonist WAY 161503 (1.0 mg/kg) decreased reward measures. Intra-NAc shell administration of muscimol (225 ng/side) and picrotoxin (125 ng/side), respectively, decreased and increased measures of reward. Intra-NAc shell baclofen (0-225 ng/side; GABA(B) receptor agonist) did not affect any ICSS measures although it increased feeding. Combining picrotoxin and WAY 161503 attenuated the effects of each. These results suggest that a 5-HT(2C) and GABA(A) receptor-mediated neuronal relationship in the NAc shell may be relevant for the regulation of brain reward pathways.
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Affiliation(s)
- Dave J Hayes
- Centre for Neuroscience, University of Alberta, Edmonton, AB, Canada.
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8
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McGinty JF. Co-localization of GABA with other neuroactive substances in the basal ganglia. PROGRESS IN BRAIN RESEARCH 2007; 160:273-84. [PMID: 17499120 DOI: 10.1016/s0079-6123(06)60016-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The dorsal striatum (caudate putamen) contains two types of GABAergic medium spiny neurons (MSNs) that are distinguished by the expression of either the opioid peptide, enkephalin, or the opioid peptide, dynorphin, as well as the tachykinin substance P. Pharmacological studies suggest that these peptides modulate local neurotransmission in the striatum in response to direct and indirect dopamine agonists. In contrast, GABA appears to have minimal impact within the striatum under these conditions. The actions of the peptide cocktail are dependent on the cellular distribution of their receptors in the striatal network. The net result of their actions is a homeostatic response that regulates striatal output and balances dopamine and glutamate receptor stimulation.
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Affiliation(s)
- Jacqueline F McGinty
- Department of Neurosciences, Medical University of South Carolina, Charleston, SC 29425, USA.
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Abstract
Many mammals spontaneously rear on their hind legs in response to novelty. The current paper is the first review of rearing behaviour, and is intended to collate findings from different perspectives that are not usually brought together. We suggest that rearing is a useful marker of environmental novelty, that the hippocampal formation is a crucial component of the system controlling rearing in novel environments, and that rearing is one of several ethological measures that can profitably be used to assess hippocampal learning and memory. Consideration is given to the following topics: the possible functions of rearing in information-gathering and escape behaviour; the modulation of rearing by various factors such as anxiety/ fear emotionality; comparative perspectives on rearing; neuroanatomical circuits involved in rearing with particular reference to the hippocampal formation and its afferents and efferents; and the role of the hippocampal formation in uncharted and mismatch environmental novelty. The review concludes with testable predictions about rearing, environmental novelty and the hippocampus.
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Affiliation(s)
- Colin Lever
- Department ofAnatomy and Developmental Biology, University College London, London, UK.
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Pal D, Mallick BN. Role of noradrenergic and GABA-ergic inputs in pedunculopontine tegmentum for regulation of rapid eye movement sleep in rats. Neuropharmacology 2006; 51:1-11. [PMID: 16616214 DOI: 10.1016/j.neuropharm.2006.02.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2005] [Revised: 02/10/2006] [Accepted: 02/13/2006] [Indexed: 01/12/2023]
Abstract
Rapid eye movement (REM) sleep disturbance is associated with several psycho-behavioral disorders, hence, it is important to understand its neural mechanism of regulation. Although it was known that the noradrenergic (NA-ergic) neurons from locus coeruleus (LC) project to the pedunculopontine tegmentum (PPT), the role of noradrenaline (NA) alone and in association with GABA, an inhibitory neurotransmitter, in PPT for REM sleep regulation was not known and was investigated in this study in freely moving normally behaving rats. Rats were surgically prepared for electrophysiological sleep-wake recording and simultaneous bilateral microinjections into PPT. 200nl of prazosin (alpha1-antagonist) or clonidine (alpha2-agonist) or propranolol (beta-antagonist) or combination of picrotoxin (GABA-A antagonist) and clonidine or vehicle (control) was microinjected bilaterally into PPT using a remote-controlled pump and the effects on REM sleep compared. Prazosin, clonidine and propranolol increased the total time spent in REM sleep whereas co-injection of picrotoxin and clonidine did not affect REM sleep. The results suggest that NA in PPT tonically inhibits REM sleep, possibly by acting on the cholinergic REM-ON neurons, while GABA inhibits the release of NA for REM sleep regulation. A model of neural connections explaining such regulation has been presented.
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Affiliation(s)
- Dinesh Pal
- School of Life Sciences, Jawaharlal Nehru University, New Delhi 110 067, India
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