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Kim DS, Santana Maldonado CM, Giulivi C, Rumbeiha WK. Metabolomic Signatures of Brainstem in Mice following Acute and Subchronic Hydrogen Sulfide Exposure. Metabolites 2024; 14:53. [PMID: 38248856 PMCID: PMC10819975 DOI: 10.3390/metabo14010053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 01/05/2024] [Accepted: 01/11/2024] [Indexed: 01/23/2024] Open
Abstract
Hydrogen sulfide (H2S) is an environmental toxicant of significant health concern. The brain is a major target in acute H2S poisoning. This study was conducted to test the hypothesis that acute and subchronic ambient H2S exposures alter the brain metabolome. Male 7-8-week-old C57BL/6J mice were exposed by whole-body inhalation to 1000 ppm H2S for 45 min and euthanized at 5 min or 72 h for acute exposure. For subchronic study, mice were exposed to 5 ppm H2S 2 h/day, 5 days/week for 5 weeks. Control mice were exposed to room air. The brainstem was removed for metabolomic analysis. Enrichment analysis showed that the metabolomic profiles in acute and subchronic H2S exposures matched with those of cerebral spinal fluid from patients with seizures or Alzheimer's disease. Acute H2S exposure decreased excitatory neurotransmitters, aspartate, and glutamate, while the inhibitory neurotransmitter, serotonin, was increased. Branched-chain amino acids and glucose were increased by acute H2S exposure. Subchronic H2S exposure within OSHA guidelines surprisingly decreased serotonin concentration. In subchronic H2S exposure, glucose was decreased, while polyunsaturated fatty acids, inosine, and hypoxanthine were increased. Collectively, these results provide important mechanistic clues for acute and subchronic ambient H2S poisoning and show that H2S alters brainstem metabolome.
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Affiliation(s)
- Dong-Suk Kim
- Department of Molecular Biosciences, School of Veterinary Medicine, UC Davis, Davis, CA 95616, USA; (D.-S.K.); (C.M.S.M.); (C.G.)
| | - Cristina M. Santana Maldonado
- Department of Molecular Biosciences, School of Veterinary Medicine, UC Davis, Davis, CA 95616, USA; (D.-S.K.); (C.M.S.M.); (C.G.)
- MRI Global, Kansas City, MO 64110, USA
| | - Cecilia Giulivi
- Department of Molecular Biosciences, School of Veterinary Medicine, UC Davis, Davis, CA 95616, USA; (D.-S.K.); (C.M.S.M.); (C.G.)
| | - Wilson Kiiza Rumbeiha
- Department of Molecular Biosciences, School of Veterinary Medicine, UC Davis, Davis, CA 95616, USA; (D.-S.K.); (C.M.S.M.); (C.G.)
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Metaxakis A, Pavlidis M, Tavernarakis N. Neuronal atg1 Coordinates Autophagy Induction and Physiological Adaptations to Balance mTORC1 Signalling. Cells 2023; 12:2024. [PMID: 37626835 PMCID: PMC10453232 DOI: 10.3390/cells12162024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 08/04/2023] [Accepted: 08/05/2023] [Indexed: 08/27/2023] Open
Abstract
The mTORC1 nutrient-sensing pathway integrates metabolic and endocrine signals into the brain to evoke physiological responses to food deprivation, such as autophagy. Nevertheless, the impact of neuronal mTORC1 activity on neuronal circuits and organismal metabolism remains obscure. Here, we show that mTORC1 inhibition acutely perturbs serotonergic neurotransmission via proteostatic alterations evoked by the autophagy inducer atg1. Neuronal ATG1 alters the intracellular localization of the serotonin transporter, which increases the extracellular serotonin and stimulates the 5HTR7 postsynaptic receptor. 5HTR7 enhances food-searching behaviour and ecdysone-induced catabolism in Drosophila. Along similar lines, the pharmacological inhibition of mTORC1 in zebrafish also stimulates food-searching behaviour via serotonergic activity. These effects occur in parallel with neuronal autophagy induction, irrespective of the autophagic activity and the protein synthesis reduction. In addition, ectopic neuronal atg1 expression enhances catabolism via insulin pathway downregulation, impedes peptidergic secretion, and activates non-cell autonomous cAMP/PKA. The above exert diverse systemic effects on organismal metabolism, development, melanisation, and longevity. We conclude that neuronal atg1 aligns neuronal autophagy induction with distinct physiological modulations, to orchestrate a coordinated physiological response against reduced mTORC1 activity.
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Affiliation(s)
- Athanasios Metaxakis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology Hellas, Nikolaou Plastira 100, 70013 Heraklion, Crete, Greece
| | - Michail Pavlidis
- Department of Biology, University of Crete, 71409 Heraklion, Crete, Greece;
| | - Nektarios Tavernarakis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology Hellas, Nikolaou Plastira 100, 70013 Heraklion, Crete, Greece
- Department of Basic Sciences, Faculty of Medicine, University of Crete, 71110 Heraklion, Crete, Greece
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Fauss GNK, Hudson KE, Grau JW. Role of Descending Serotonergic Fibers in the Development of Pathophysiology after Spinal Cord Injury (SCI): Contribution to Chronic Pain, Spasticity, and Autonomic Dysreflexia. BIOLOGY 2022; 11:234. [PMID: 35205100 PMCID: PMC8869318 DOI: 10.3390/biology11020234] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 01/27/2022] [Accepted: 01/29/2022] [Indexed: 12/12/2022]
Abstract
As the nervous system develops, nerve fibers from the brain form descending tracts that regulate the execution of motor behavior within the spinal cord, incoming sensory signals, and capacity to change (plasticity). How these fibers affect function depends upon the transmitter released, the receptor system engaged, and the pattern of neural innervation. The current review focuses upon the neurotransmitter serotonin (5-HT) and its capacity to dampen (inhibit) neural excitation. A brief review of key anatomical details, receptor types, and pharmacology is provided. The paper then considers how damage to descending serotonergic fibers contributes to pathophysiology after spinal cord injury (SCI). The loss of serotonergic fibers removes an inhibitory brake that enables plasticity and neural excitation. In this state, noxious stimulation can induce a form of over-excitation that sensitizes pain (nociceptive) circuits, a modification that can contribute to the development of chronic pain. Over time, the loss of serotonergic fibers allows prolonged motor drive (spasticity) to develop and removes a regulatory brake on autonomic function, which enables bouts of unregulated sympathetic activity (autonomic dysreflexia). Recent research has shown that the loss of descending serotonergic activity is accompanied by a shift in how the neurotransmitter GABA affects neural activity, reducing its inhibitory effect. Treatments that target the loss of inhibition could have therapeutic benefit.
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Affiliation(s)
| | | | - James W. Grau
- Department of Psychological and Brain Sciences, Texas A&M University, College Station, TX 77843, USA; (G.N.K.F.); (K.E.H.)
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Sahebi Vaighan N, Parhiz S, Sabetkasaei M, Moini Zanjani T, Zarei M. Paroxetine effects on morphine analgesic tolerance in rats. Scand J Pain 2022; 22:186-192. [PMID: 34298592 DOI: 10.1515/sjpain-2021-0009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 07/05/2021] [Indexed: 11/15/2022]
Abstract
OBJECTIVES To alleviate different pain intensities, morphine administration has been extensively used. However, prolonged administration of morphine leads to a progressive decline of its analgesic effect which limits their overall utility. Morphine tolerance is considered as a challenging issue for the treatment of both acute and chronic pain. We conducted this study in rats to investigate the effect of paroxetine on morphine tolerance when used preemptively or after morphine tolerance had developed. METHODS Male Wistar rats (weight 250-300 g, n=10) were used to evaluate the effects of paroxetine on tolerance to morphine. In order to induce tolerance, daily intraperitoneal injection of morphine (7 mg/kg) was done. After tolerance induction, a group of animals received intraperitoneal injection of 10 mg/kg paroxetine 30 min prior to each morphine dose. In another trial, to investigate the potential of paroxetine to prevent tolerance to morphine, animals were pretreated with 10 mg/kg paroxetine 30 min before morphine administration. In the control groups, 10 mL/kg of saline was injected. The behavioral test (tail-flick test) was done for all groups. RESULTS Our data showed that paroxetine significantly reversed tolerance to morphine when used after tolerance induction (p<0.001). However, administration of paroxetine before occurrence of tolerance had no effect. CONCLUSIONS We conclude that paroxetine could decrease tolerance to morphine when used after the occurrence of morphine tolerance, while it was not able to prevent morphine tolerance when administered preemptively. ETHICAL COMMITTEE NUMBER IRIB.SBMU.MSP.REC.1394.098.
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Affiliation(s)
- Navideh Sahebi Vaighan
- Department of Pharmacology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Soha Parhiz
- Department of Pharmacology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Masoumeh Sabetkasaei
- Department of Pharmacology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Taraneh Moini Zanjani
- Department of Pharmacology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Malek Zarei
- Department of Pharmacology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Rovný R, Marko M, Minárik G, Riečanský I. Absence of a significant interaction of two common NOS1 and 5-HTT polymorphisms on sensorimotor gating in humans. Physiol Res 2021; 70:S387-S395. [PMID: 35099257 DOI: 10.33549/physiolres.934819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The neurotransmitter serotonin has been critically implicated in the pathogenesis of several mental disorders. The serotonin transporter (5-HTT) is a key regulator of serotonergic neurotransmission and its genetic variability is associated with increased risk of psychopathology. One well known polymorphic locus in the 5-HTT gene affecting its expression is a tandem repeat in the promoter region (5-HTTLPR). It has been reported that 5-HTT is functionally coupled with the neuronal nitric oxide synthase (NOS1 or nNOS), an enzyme catalyzing the production of nitric oxide (NO). We have previously demonstrated that a tandem repeat polymorphism in the promoter of NOS1 exon 1f (Ex1f-VNTR) is associated with sensorimotor gating, a marker of inhibitory processing and a well established endophenotype of several neuropsychiatric disorders. Here we investigated the combined genetic effects of NOS1 Ex1f-VNTR and 5-HTTLPR on sensorimotor gating, measured by prepulse inhibition (PPI) of the acoustic startle reflex, in 164 healthy adults. We found no evidence for the interaction between NOS1 Ex1f-VNTR and 5-HTTLPR on PPI. PPI was associated with NOS1 Ex1f-VNTR, but not 5-HTTLPR. Our data suggest that while NOS1 plays a role in sensorimotor gating, the nitrergic pathway of gating regulation does not involve the action of 5-HTT.
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Affiliation(s)
- R Rovný
- Department of Behavioural Neuroscience, Institute of Normal and Pathological Physiology, Centre of Experimental Medicine, Slovak Academy of Sciences, Bratislava, Slovak Republic.
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Vortioxetine increases absence-like seizures in WAG/Rij rats but decreases penicillin- and pentylenetetrazole-induced seizures in Wistar rats. Epilepsy Behav 2021; 116:107797. [PMID: 33561766 DOI: 10.1016/j.yebeh.2021.107797] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 01/08/2021] [Accepted: 01/09/2021] [Indexed: 11/20/2022]
Abstract
AIM Depression is the major psychiatric disorder in patients with epilepsy. Vortioxetine is a novel antidepressant drug for the treatment of major depressive disorders. In the present study, effects of vortioxetine were evaluated in different experimental epilepsy models of rats. MATERIALS AND METHODS Fifty-six adult male Wistar rats and 28 WAG/Rij rats were divided into 12 groups of 7 rats each. Experiments were conducted with penicillin (500 IU, i.c.) and pentylenetetrazole models (50 mg/kg, intraperitoneally (i.p.)) in Wistar rats and genetic absence epileptic WAG/Rij rats. The vortioxetine (1, 5, or 10 mg/kg, i.p.) was evaluated in these three models. All groups were compared with their control groups. RESULTS In the penicillin-induced seizure model, 1, 5, or 10 mg/kg vortioxetine administration significantly decreased mean spike frequency. In the pentylenetetrazole-induced seizure model, 1, 5, or 10 mg/kg vortioxetine demonstrated a significant dose-dependent decrease in mean spike frequency, an increase in the latency to minor and major seizures, and a decrease in total duration of major seizure and convulsion stage. In genetic absence epileptic WAG/Rij rats, 1 mg/kg vortioxetine caused no significant alteration in the number and duration of SWDs compared to the controls, while 5 and 10 mg/kg doses of vortioxetine increased the number and duration of SWDs. Amplitude of the epileptiform activity did not change in any of the experimental epilepsy models. CONCLUSION The results of this study suggested that vortioxetine has anticonvulsant activity in penicillin- and pentylenetetrazole-induced seizure models. However, it exhibited proconvulsant activity in the absence epileptic WAG/Rij rats.
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Ishola AO, Imam A, Ajao MS. Datumetine exposure alters hippocampal neurotransmitters system in C57BL/6 mice. Drug Chem Toxicol 2020; 45:785-798. [PMID: 32847421 DOI: 10.1080/01480545.2020.1776315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Our previous study showed that datumetine modulates NMDAR activity with long term exposure leading to memory deficit and altered NMDAR signaling. We aim to explore the neurotransmitters perturbations of acute datumetine-NMDAR interaction. Fifteen C57/BL6 mice were used for the study, they are divided into three groups of 5 animals each. Animals were administered DMSO (DMSO/Control), 0.25 mg/kg body weight of datumetine (0.25 Datumetine) and 1 mg/kg bodyweight of datumetine (1.0 Datumetine) intraperitoneally for 14 days. At the end of treatment, animals were euthanized in isofluorane chamber, perfused transcardially with 1XPBS followed by PFA. Immunofluorescence procedure was done to check the distribution of neurons, astrocytes, microglia and major neuronal subtypes in the hippocampus. Expansion and electron microscopy techniques were used to assess the condition of the synapses. Quantitative data were expressed as mean ± SEM and analyzed using ANOVA with Tukey post hoc using p < 0.05 as significant. Datumetine increased the expression of CD11b, GFAP, vGlut1, GABA, CHRNA7 and TH while expression of TrPH and NeuN were reduced in the hippocampus compared to control animals. Synaptic loss was evident in datumetine exposed animals with reduced synaptic vesicles accompanied by a thickness of postsynaptic density than that of control animals. This study concludes that acute datumetine exposure alters hippocampal neurotransmitter systems.
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Affiliation(s)
- Azeez Olakunle Ishola
- Department of Anatomy, University of Ilorin, Ilorin, Nigeria.,Department of Anatomy, Afe Babalola University, Ado-Ekiti, Nigeria
| | - Aminu Imam
- Department of Anatomy, University of Ilorin, Ilorin, Nigeria
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Júnior ALG, Tchekalarova JD, Conceição Machado K, Silva SWC, Paz MFCJ, Nogueira TR, Matos Monteiro Lira BS, Zihad SNK, Islam MT, Ali ES, Sousa Rios MA, Carvalho ALM, Silva Lopes L, Saha SK, Mubarak MS, Carvalho Melo‐Cavalcante AA. Antidepressant‐like effect of anacardic acid in mice via the L‐arginine–nitric oxide–serotonergic system. Phytother Res 2019; 33:2126-2138. [DOI: 10.1002/ptr.6407] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 05/01/2019] [Accepted: 05/18/2019] [Indexed: 11/09/2022]
Affiliation(s)
- Antonio Luiz Gomes Júnior
- Laboratório de Pesquisa em Neuroquímica Experimental do Programa de Pós‐graduação em Ciências FarmacêuticasUniversidade Federal do Piauí Teresina Brazil
- Laboratório de Toxicidade Genética do Programa de Pós‐graduação em Ciências FarmacêuticasUniversidade Federal do Piauí Teresina Brazil
- Programa de Pós‐Graduação em Biotecnologia (RENORBIO)Universidade Federal do Piauí Teresina Brazil
| | | | - Keylla Conceição Machado
- Laboratório de Pesquisa em Neuroquímica Experimental do Programa de Pós‐graduação em Ciências FarmacêuticasUniversidade Federal do Piauí Teresina Brazil
- Laboratório de Toxicidade Genética do Programa de Pós‐graduação em Ciências FarmacêuticasUniversidade Federal do Piauí Teresina Brazil
- Programa de Pós‐Graduação em Biotecnologia (RENORBIO)Universidade Federal do Piauí Teresina Brazil
| | - Samara Wanessa Cardoso Silva
- Laboratório de Pesquisa em Neuroquímica Experimental do Programa de Pós‐graduação em Ciências FarmacêuticasUniversidade Federal do Piauí Teresina Brazil
- Laboratório de Toxicidade Genética do Programa de Pós‐graduação em Ciências FarmacêuticasUniversidade Federal do Piauí Teresina Brazil
| | | | - Tiago Rocha Nogueira
- Grupo de Inovação Tecnológicas e Especialidades Químicas (GRINTEQUI)Universidade Federal do Ceará Fortaleza Brazil
| | - Beatriz Santiago Matos Monteiro Lira
- Laboratório de Pesquisa em Neuroquímica Experimental do Programa de Pós‐graduação em Ciências FarmacêuticasUniversidade Federal do Piauí Teresina Brazil
- Laboratório de Toxicidade Genética do Programa de Pós‐graduação em Ciências FarmacêuticasUniversidade Federal do Piauí Teresina Brazil
| | | | - Muhammad Torequl Islam
- Department for Management of Science and Technology DevelopmentTon Duc Thang University Ho Chi Minh City Vietnam
- Faculty of PharmacyTon Duc Thang University Ho Chi Minh City Vietnam
| | - Eunus S. Ali
- Gaco Pharmaceuticals Limited, Dhaka‐1000, Bangladesh, and College of Medicine and Public HealthFlinders University Adelaide South Australia Australia
| | - Maria Alexsandra Sousa Rios
- Grupo de Inovação Tecnológicas e Especialidades Químicas (GRINTEQUI)Universidade Federal do Ceará Fortaleza Brazil
| | - André Luis Menezes Carvalho
- Grupo de Inovação Tecnológicas e Especialidades Químicas (GRINTEQUI)Universidade Federal do Ceará Fortaleza Brazil
| | - Luciano Silva Lopes
- Laboratório de Pesquisa em Neuroquímica Experimental do Programa de Pós‐graduação em Ciências FarmacêuticasUniversidade Federal do Piauí Teresina Brazil
| | | | | | - Ana Amélia Carvalho Melo‐Cavalcante
- Laboratório de Toxicidade Genética do Programa de Pós‐graduação em Ciências FarmacêuticasUniversidade Federal do Piauí Teresina Brazil
- Programa de Pós‐Graduação em Biotecnologia (RENORBIO)Universidade Federal do Piauí Teresina Brazil
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Hassan A, Robinson M, Willerth SM. Modeling the Effects of Yoga on the Progression of Alzheimer's Disease in a Dish. Cells Tissues Organs 2019; 206:263-271. [PMID: 31121578 DOI: 10.1159/000499503] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Accepted: 03/11/2019] [Indexed: 12/18/2022] Open
Abstract
Alzheimer's disease (AD) accounts for 80% of all dementia cases, making it the most common form of dementia. Aging serves as the main risk factor for AD, but early onset AD can also occur in individuals younger than 65 years. AD results from progressive neurodegeneration leading to dysfunctional synaptic transmission in the brain. The cascade hypothesis of AD states that amyloid precursor protein (APP) metabolism becomes impaired either by mutation or an interleukin-mediated stress response to injury, resulting in the splicing of harmful oligomeric forms of amyloid beta (Aβ). These oligomers disrupt extracellular receptor binding, intracellular function, and cellular membrane integrity. Yoga and meditative practices slow the progression of the cognitive decline associated with AD. However, the biological mechanisms underlying this therapeutic effect remain elusive. Here, we investigated the ability of neurotransmitters released during yoga and meditative practices to rescue neurons from synaptic dysfunction in an in vitro Alzheimer's model created by culturing basal forebrain cholinergic neurons with physiologically relevant levels of the I-42 isoform of oligomeric Aβ (OΑβI-42). We found that the neurotransmitters dopamine and histamine produce a cooperative action with serotonin to reverse the loss of choline acetyltransferase (CHaT) by OΑβI-42. The loss of ChaT, the enzyme responsible for processing the cholinergic neurotransmitter acetylcholine, contributes to the synaptic dysfunction experienced during AD. These neurotransmitters inhibit nitric oxide synthesis caused by OΑβI-42, preventing oxidative and nitrosative stress. Serotonin activates an alternate cleavage of APP to produce a fragment with known neurotrophic effects, giving it the unique ability to inhibit the OΑβI-42 production cycle. We hypothesize here that these concerted actions lead to the protection of cholinergic synaptic transmission in AD.
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Affiliation(s)
- Adithy Hassan
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
| | - Meghan Robinson
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
| | - Stephanie M Willerth
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada, .,Biomedical Engineering Program, University of Victoria, Victoria, British Columbia, Canada, .,Department of Mechanical Engineering, Faculty of Engineering, University of Victoria, Victoria, British Columbia, Canada, .,Centre for Biomedical Research, Faculty of Engineering, University of Victoria, Victoria, British Columbia, Canada, .,International Collaboration for Repair Discovery, University of British Columbia, Vancouver, British Columbia, Canada,
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de Oliveira FR, Fantucci MZ, Adriano L, Valim V, Cunha TM, Louzada-Junior P, Rocha EM. Neurological and Inflammatory Manifestations in Sjögren's Syndrome: The Role of the Kynurenine Metabolic Pathway. Int J Mol Sci 2018; 19:ijms19123953. [PMID: 30544839 PMCID: PMC6321004 DOI: 10.3390/ijms19123953] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 12/04/2018] [Accepted: 12/06/2018] [Indexed: 12/16/2022] Open
Abstract
For decades, neurological, psychological, and cognitive alterations, as well as other glandular manifestations (EGM), have been described and are being considered to be part of Sjögren's syndrome (SS). Dry eye and dry mouth are major findings in SS. The lacrimal glands (LG), ocular surface (OS), and salivary glands (SG) are linked to the central nervous system (CNS) at the brainstem and hippocampus. Once compromised, these CNS sites may be responsible for autonomic and functional disturbances that are related to major and EGM in SS. Recent studies have confirmed that the kynurenine metabolic pathway (KP) can be stimulated by interferon-γ (IFN-γ) and other cytokines, activating indoleamine 2,3-dioxygenase (IDO) in SS. This pathway interferes with serotonergic and glutamatergic neurotransmission, mostly in the hippocampus and other structures of the CNS. Therefore, it is plausible that KP induces neurological manifestations and contributes to the discrepancy between symptoms and signs, including manifestations of hyperalgesia and depression in SS patients with weaker signs of sicca, for example. Observations from clinical studies in acquired immune deficiency syndrome (AIDS), graft-versus-host disease, and lupus, as well as from experimental studies, support this hypothesis. However, the obtained results for SS are controversial, as discussed in this study. Therapeutic strategies have been reexamined and new options designed and tested to regulate the KP. In the future, the confirmation and application of this concept may help to elucidate the mosaic of SS manifestations.
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Affiliation(s)
- Fabíola Reis de Oliveira
- Ribeirao Preto Medical School, Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, SP 14049-900 Brazil.
| | - Marina Zilio Fantucci
- Ribeirao Preto Medical School, Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, SP 14049-900 Brazil.
| | - Leidiane Adriano
- Ribeirao Preto Medical School, Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, SP 14049-900 Brazil.
| | - Valéria Valim
- Espírito Santo Federal University, Vitoria, ES 29075-910, Brazil.
| | - Thiago Mattar Cunha
- Ribeirao Preto Medical School, Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, SP 14049-900 Brazil.
| | - Paulo Louzada-Junior
- Ribeirao Preto Medical School, Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, SP 14049-900 Brazil.
| | - Eduardo Melani Rocha
- Ribeirao Preto Medical School, Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, SP 14049-900 Brazil.
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Ostadhadi S, Norouzi-Javidan A, Chamanara M, Akbarian R, Imran-Khan M, Ghasemi M, Dehpour AR. Involvement of NMDA receptors in the antidepressant-like effect of tramadol in the mouse forced swimming test. Brain Res Bull 2017; 134:136-141. [DOI: 10.1016/j.brainresbull.2017.07.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 07/21/2017] [Accepted: 07/24/2017] [Indexed: 01/16/2023]
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Chilmonczyk Z, Bojarski AJ, Pilc A, Sylte I. Functional Selectivity and Antidepressant Activity of Serotonin 1A Receptor Ligands. Int J Mol Sci 2015; 16:18474-506. [PMID: 26262615 PMCID: PMC4581256 DOI: 10.3390/ijms160818474] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 07/29/2015] [Accepted: 07/31/2015] [Indexed: 01/11/2023] Open
Abstract
Serotonin (5-HT) is a monoamine neurotransmitter that plays an important role in physiological functions. 5-HT has been implicated in sleep, feeding, sexual behavior, temperature regulation, pain, and cognition as well as in pathological states including disorders connected to mood, anxiety, psychosis and pain. 5-HT1A receptors have for a long time been considered as an interesting target for the action of antidepressant drugs. It was postulated that postsynaptic 5-HT1A agonists could form a new class of antidepressant drugs, and mixed 5-HT1A receptor ligands/serotonin transporter (SERT) inhibitors seem to possess an interesting pharmacological profile. It should, however, be noted that 5-HT1A receptors can activate several different biochemical pathways and signal through both G protein-dependent and G protein-independent pathways. The variables that affect the multiplicity of 5-HT1A receptor signaling pathways would thus result from the summation of effects specific to the host cell milieu. Moreover, receptor trafficking appears different at pre- and postsynaptic sites. It should also be noted that the 5-HT1A receptor cooperates with other signal transduction systems (like the 5-HT1B or 5-HT2A/2B/2C receptors, the GABAergic and the glutaminergic systems), which also contribute to its antidepressant and/or anxiolytic activity. Thus identifying brain specific molecular targets for 5-HT1A receptor ligands may result in a better targeting, raising a hope for more effective medicines for various pathologies.
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Affiliation(s)
- Zdzisław Chilmonczyk
- National Medicines Institute, Chełmska 30/34, 00-725 Warszawa, Poland.
- Institute of Nursing and Health Sciences, University of Rzeszów, W. Kopisto 2A, 35-310 Rzeszów, Poland.
| | - Andrzej Jacek Bojarski
- Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Kraków, Poland.
| | - Andrzej Pilc
- Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Kraków, Poland.
| | - Ingebrigt Sylte
- Faculty of Health Sciences, University of Tromsø-The Arctic University of Norway, No-9037 Tromsø, Norway.
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Maximino C, Lima MG, Batista EDJO, Oliveira KRHM, Herculano AM. Interaction between 5-HT1B receptors and nitric oxide in zebrafish responses to novelty. Neurosci Lett 2014; 588:54-6. [PMID: 25545556 DOI: 10.1016/j.neulet.2014.12.049] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 12/17/2014] [Accepted: 12/23/2014] [Indexed: 10/24/2022]
Abstract
Nitric oxide (NO) and serotonin (5-HT) interact at the molecular and systems levels to control behavioral variables, including agression, fear, and reactions to novelty. In zebrafish, the 5-HT1B receptor has been implicated in anxiety and reactions to novelty, while the 5-HT1A receptor is associated with anxiety-like behavior; this role of the 5-HT1A receptor is mediated by NO. This work investigated whether NO also participates in the mediation of novelty responses by the 5-HT1B receptor. The 5-HT1B receptor inverse agonist SB 224,289 decreased bottom-dwelling and erratic swimming in zebrafish; the effects on bottom-dwelling, but not on erratic swimming, were blocked by pre-treatment with the nitric oxide synthase inhibitor L-NAME. These effects underline a novel mechanism by which 5-HT controls zebrafish reactivity to novel environments, with implications for the study of neotic reactions, exploratory behavior, and anxiety-like states.
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Affiliation(s)
- Caio Maximino
- Laboratório de Neurociências e Comportamento "Frederico Guilherme Graeff", Universidade do Estado do Pará, Marabá, PA, Brazil; International Zebrafish Neuroscience Research Consortium, Brazil.
| | - Monica Gomes Lima
- Laboratório de Neurociências e Comportamento "Frederico Guilherme Graeff", Universidade do Estado do Pará, Marabá, PA, Brazil; International Zebrafish Neuroscience Research Consortium, Brazil; Laboratório de Neuroendocrinologia, Universidade Federal do Pará, Belém, PA, Brazil
| | | | | | - Anderson Manoel Herculano
- International Zebrafish Neuroscience Research Consortium, Brazil; Laboratório de Neuroendocrinologia, Universidade Federal do Pará, Belém, PA, Brazil
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Herculano AM, Puty B, Miranda V, Lima MG, Maximino C. Interactions between serotonin and glutamate-nitric oxide pathways in zebrafish scototaxis. Pharmacol Biochem Behav 2014; 129:97-104. [PMID: 25536532 DOI: 10.1016/j.pbb.2014.12.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 12/11/2014] [Accepted: 12/16/2014] [Indexed: 11/26/2022]
Abstract
NMDA receptors have been implicated in the acute response to stress, possibly mediated the nitric oxide pathway; serotonin has also been implicated in these responses, and has recently been shown to modulate the nitric oxide pathway via 5-HT1 and 5-HT2 receptors. In this work, we compare the effects of NMDA and a 5-HT1A receptor ligands on light/dark preference in adult zebrafish, and investigate whether nitric oxide mediates the effects of such drugs. The noncompetitive NMDA receptor antagonist MK-801 decreased dark preference (scototaxis), while NMDA increased it; the effects of NMDA were completely blocked by pretreatment with the nitric oxide synthase (NOS) antagonist L-NAME. SNP, a nitric oxide donor, produced a bell-shaped dose-response profile on scototaxis. Treatment with 5-HTP increased scototaxis, an effect which was potentiated by pre-treatment with NMDA, but not MK-801, and partially blocked by L-NAME. The 5-HT1A receptor antagonist WAY 100,635 decreased scototaxis, an effect which was completely blocked by L-NAME. These results suggest that tonic NOS inhibition is an important downstream effector of 5-HT1A receptors in the regulation of dark preference behavior in zebrafish, and that NOS is also under phasic independent control by NMDA receptors.
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Affiliation(s)
- Anderson Manoel Herculano
- Laboratório de Neuroendocrinologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, PA, Brazil; Zebrafish Neuroscience Research Consortium, USA
| | - Bruna Puty
- Laboratório de Neuroendocrinologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, PA, Brazil
| | - Vanessa Miranda
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, PA, Brazil
| | - Monica Gomes Lima
- Zebrafish Neuroscience Research Consortium, USA; Departamento de Morfologia e Ciências Fisiológicas, Centro de Ciências Biológicas e da Saúde, Universidade do Estado do Pará, Marabá, PA, Brazil
| | - Caio Maximino
- Zebrafish Neuroscience Research Consortium, USA; Departamento de Morfologia e Ciências Fisiológicas, Centro de Ciências Biológicas e da Saúde, Universidade do Estado do Pará, Marabá, PA, Brazil.
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15
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Alteration in 5-HT2C, NMDA Receptor and IP3 in Cerebral Cortex of Epileptic Rats: Restorative Role of Bacopa monnieri. Neurochem Res 2014; 40:216-25. [DOI: 10.1007/s11064-014-1472-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Revised: 09/30/2014] [Accepted: 10/30/2014] [Indexed: 12/21/2022]
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16
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Szőnyi A, Mayer MI, Cserép C, Takács VT, Watanabe M, Freund TF, Nyiri G. The ascending median raphe projections are mainly glutamatergic in the mouse forebrain. Brain Struct Funct 2014; 221:735-51. [PMID: 25381463 DOI: 10.1007/s00429-014-0935-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 10/28/2014] [Indexed: 12/26/2022]
Abstract
The median raphe region (MRR) is thought to be serotonergic and plays an important role in the regulation of many cognitive functions. In the hippocampus (HIPP), the MRR exerts a fast excitatory control, partially through glutamatergic transmission, on a subpopulation of GABAergic interneurons that are key regulators of local network activity. However, not all receptors of this connection in the HIPP and in synapses established by MRR in other brain areas are known. Using combined anterograde tracing and immunogold methods, we show that the GluN2A subunit of the NMDA receptor is present in the synapses established by MRR not only in the HIPP, but also in the medial septum (MS) and in the medial prefrontal cortex (mPFC) of the mouse. We estimated similar amounts of NMDA receptors in these synapses established by the MRR and in local adjacent excitatory synapses. Using retrograde tracing and confocal laser scanning microscopy, we found that the majority of the projecting cells of the mouse MRR contain the vesicular glutamate transporter type 3 (vGluT3). Furthermore, using double retrograde tracing, we found that single cells of the MRR can innervate the HIPP and mPFC or the MS and mPFC simultaneously, and these double-projecting cells are also predominantly vGluT3-positive. Our results indicate that the majority of the output of the MRR is glutamatergic and acts through NMDA receptor-containing synapses. This suggests that key forebrain areas receive precisely targeted excitatory input from the MRR, which is able to synchronously modify activity in those regions via individual MRR cells with dual projections.
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Affiliation(s)
- András Szőnyi
- Laboratory of Cerebral Cortex Research, Institute of Experimental Medicine Hungarian Academy of Sciences, Budapest, 1083, Hungary.,János Szentágothai Doctoral School of Neurosciences, Semmelweis University, Budapest, 1085, Hungary
| | - Márton I Mayer
- Laboratory of Cerebral Cortex Research, Institute of Experimental Medicine Hungarian Academy of Sciences, Budapest, 1083, Hungary
| | - Csaba Cserép
- Laboratory of Cerebral Cortex Research, Institute of Experimental Medicine Hungarian Academy of Sciences, Budapest, 1083, Hungary
| | - Virág T Takács
- Laboratory of Cerebral Cortex Research, Institute of Experimental Medicine Hungarian Academy of Sciences, Budapest, 1083, Hungary
| | - Masahiko Watanabe
- Department of Anatomy, Hokkaido University School of Medicine, Sapporo, 060-8638, Japan
| | - Tamás F Freund
- Laboratory of Cerebral Cortex Research, Institute of Experimental Medicine Hungarian Academy of Sciences, Budapest, 1083, Hungary
| | - Gábor Nyiri
- Laboratory of Cerebral Cortex Research, Institute of Experimental Medicine Hungarian Academy of Sciences, Budapest, 1083, Hungary.
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Panther P, Nullmeier S, Dobrowolny H, Schwegler H, Wolf R. CPB-K mice a mouse model of schizophrenia? Differences in dopaminergic, serotonergic and behavioral markers compared to BALB/cJ mice. Behav Brain Res 2012; 230:215-28. [PMID: 22454846 DOI: 10.1016/j.bbr.2012.02.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Schizophrenia is characterized by disturbances in social behavior, sensorimotor gating and cognitive function, that are discussed to be caused by a termination of different transmitter systems. Beside morphological alterations in cortical and subcortical areas reduced AMPA- NMDA-, 5-HT2-receptor densities and increased 5-HT1-receptor densities are found in the hippocampus.The two inbred mouse strains CPB-K and BALB/cJ are known to display considerable differences in cognitive function and prepulse inhibition, a stable marker of sensorimotor gating. Furthermore, CPB-K mice exhibit lower NMDA-, AMPA- and increased 5-HT-receptor densities in the hippocampus as compared to BALB/cJ mice. We investigated both mouse strains in social interaction test for differences in social behavior and with immuncytochemical approaches for alterations of dopaminergic and serotonergic parameters. Our results can be summarized as follows: compared to BALB/cJ, CPB-K mice showed:(1) significantly reduced traveling distance and number of contacts in social interaction test, (2) differences in the number of serotonin transporter-immunoreactive neurons and volume of raphe nuclei and a lower serotonergic fiber density in the ventral and dorsal hippocampal subfields CA1 and CA3, (3) no alterations of dopaminergic markers like neuron number, neuron density and volume in subregions of substantia nigra and ventral tegmental area, but a significantly higher dopaminergic fiber density in the dorsal hippocampus, the ventral hippocampus of CA1 and gyrus dentatus, (4) no significant differences in serotonergic and dopaminergic fiber densities in the amygdala.Based on our results and previous studies, CPB-K mice compared to BALB/cJ may serve as an important model to understand the interaction of the serotonergic and dopaminergic system and their impact on sensorimotor gating and cognitive function as related to neuropsychiatric disorders like schizophrenia.
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Affiliation(s)
- P Panther
- Institute of Anatomy, University of Magdeburg, Haus 43, Leipziger Str. 44, 39120 Magdeburg, Germany.
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Presynaptic mGlu7 receptors control GABA release in mouse hippocampus. Neuropharmacology 2012; 66:215-24. [PMID: 22564442 DOI: 10.1016/j.neuropharm.2012.04.020] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2011] [Revised: 04/05/2012] [Accepted: 04/19/2012] [Indexed: 11/24/2022]
Abstract
The functional role of presynaptic release-regulating metabotropic glutamate type 7 (mGlu7) receptors in hippocampal GABAergic terminals was investigated. Mouse hippocampal synaptosomes were preloaded with [(3)H]D-γ-aminobutyric acid ([(3)H]GABA) and then exposed in superfusion to 12 mM KCl. The K(+)-evoked [(3)H]GABA release was inhibited by the mGlu7 allosteric agonist N,N'-dibenzyhydryl-ethane-1,2-diamine dihydrochloride (AMN082, 0.001-10 μM), as well as by the group III mGlu receptor agonist l-(+)-2-amino-4-phosphonobutyric acid [(l)-AP4, 0.01-1 mM]. The mGlu8 receptor agonist (S)-3,4-dicarboxyphenylglycine [(S)-3,4-DCPG, 10-100 nM] was ineffective. AMN082 and (l)-AP4-induced effects were recovered by the mGlu7 negative allosteric modulator (NAM) 6-(4-methoxyphenyl)-5-methyl-3-(4-pyridinyl)-isoxazolo[4,5-c]pyridin-4(5H)-one hydrochloride (MMPIP). AMN082 also inhibited in a MMPIP-sensitive manner the K(+)-evoked release of endogenous GABA. AMN082 and the adenylyl cyclase (AC) inhibitor MDL-12,330A reduced [(3)H]GABA exocytosis in a 8-Br-cAMP-sensitive. AMN082-inhibitory effect was additive to that caused by (-)baclofen, but insensitive to the GABA(B) antagonist 3-[[(3,4-Dichlorophenyl)methyl]amino]propyl] diethoxymethyl) phosphinic acid (CGP52432). Conversely, (-)baclofen-induced inhibition of GABA exocytosis was insensitive to MMPIP. Finally, the forskolin-evoked [(3)H]GABA release was reduced by AMN082 or (-)baclofen but abolished when the two agonists were added concomitantly. Mouse hippocampal synaptosomal plasmamembranes posses mGlu7 receptor proteins; confocal microscopy analysis unveiled that mGlu7 proteins colocalize with syntaxin-1A (Stx-1A), with vesicular GABA transporter (VGAT)-proteins and with GABA(B) receptor subunit proteins. We propose that presynaptic inhibitory mGlu7 heteroreceptors, negatively coupled to AC-dependent intraterminal pathway, exist in mouse hippocampal GABA-containing terminals, where they colocalize, but do not functionally cross-talk, with GABA(B) autoreceptors. This article is part of a Special Issue entitled 'Metabotropic Glutamate Receptors'.
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Shim HJ, Lee LH, Huh Y, Lee SY, Yeo SG. Age-related changes in the expression of NMDA, serotonin, and GAD in the central auditory system of the rat. Acta Otolaryngol 2012; 132:44-50. [PMID: 22054020 DOI: 10.3109/00016489.2011.622785] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
CONCLUSIONS We suggest that age-induced changes of serotonin, N-methyl-d-aspartate receptor (NMDAR), and glutamate decarboxylase (GAD) expression in rats are dependent on the specific location in the central auditory system (CAS). OBJECTIVES Despite the importance of understanding changes in neurotransmitters during presbycusis, only a few studies have assessed age-associated changes in neurotransmitter at each level of the CAS. We therefore evaluated effects of aging on neurotransmission in the CAS of rats. METHODS The concentrations of serotonin, NMDAR, and GAD were assayed immunohistochemically in the cochlear nucleus (CN), superior olivary nucleus (SON), inferior colliculus (IC), medial geniculate body (MGB), and auditory cortex (AC) of Sprague-Dawley rats, aged 2 weeks (n = 20) or 24 months (n = 20). RESULTS The total number of neuronal cell bodies of the CAS did not differ significantly at each level between young and aged rats (p > 0.05). Serotonin expression was increased with age in the IC and MGB, but decreased in the CN, SON, and AC (p < 0.05). NMDAR was significantly higher in the CN, MGB, and AC of aged compared with young rats, but was significantly decreased over time in the SOC and IC (p < 0.05). GAD67 was increased with age in the MGB and AC and decreased in the CN and SON (p < 0.05), but was not changed in the IC.
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Affiliation(s)
- Hyun Joon Shim
- Department of Otorhinolaryngology, Eulji Hospital, Eulji University School of Medicine, Seoul, Korea
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20
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Zeni ALB, Zomkowski ADE, Dal-Cim T, Maraschin M, Rodrigues ALS, Tasca CI. Antidepressant-like and neuroprotective effects of Aloysia gratissima: investigation of involvement of L-arginine-nitric oxide-cyclic guanosine monophosphate pathway. JOURNAL OF ETHNOPHARMACOLOGY 2011; 137:864-874. [PMID: 21767626 DOI: 10.1016/j.jep.2011.07.009] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2011] [Revised: 06/10/2011] [Accepted: 07/03/2011] [Indexed: 05/31/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Aloysia gratissima (Gill. et Hook) Tronc. (Verbenaceae) is used traditionally for the treatment of headache, bronchitis, and nervous systems disorders including depression. AIM OF THE STUDY To investigate the antidepressant-like and neuroprotective effects of Aloysia gratissima aqueous extract (AE) and the involvement of l-arginine-nitric oxide (NO)-cyclic guanosine monophosphate (cGMP) pathway. MATERIALS AND METHODS The antidepressant-like effect of AE was evaluated through behavioral despair in forced swimming test (FST) and tail suspension test (TST). Swiss albino mice were treated by oral route and after 1h were analyzed the time of immobility in the FST and TST. In addition, the neuroprotective effect of AE against glutamate excitotoxicity was evaluate through cell viability of hippocampal slices, phosphorylation of Akt, and the immunocontent of inducible oxide nitric synthase (iNOS) were investigated by western blotting. RESULTS The immobility time in the FST and TST were reduced by AE (100-1000 and 10-300 mg/kg, respectively). The antidepressant-like effect of AE in the TST was prevented by the pretreatment with N-methyl-d-aspartate (NMDA), l-arginine or sildenafil. The subeffective dose of AE produced a synergistic antidepressant-like effect with MK-801 (an antagonist of NMDA receptor), methylene blue, l-NNA (an inhibitor of NO synthase) or ODQ (an inhibitor of soluble guanylate cyclase). In ex vivo experiments, pretreatment with AE prevented the loss of cell viability induced by glutamate, thus affording neuroprotection. Glutamate toxicity caused a decreased Akt phosphorylation and an increased iNOS expression. CONCLUSIONS The present study provides convincing evidence of neuroprotection and the involvement of the l-arginine-NO-cGMP pathway in the antidepressant-like effect of AE. Therefore, AE could be of potential interest for the treatment of depressive disorders and neurological conditions associated with glutamate excitotoxicity.
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Affiliation(s)
- Ana Lúcia Bertarello Zeni
- Biochemistry Department, Biological Sciences Center, Federal University of Santa Catarina, Florianópolis 88040-900, SC, Brazil
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Lou JS, Li CY, Yang XC, Fang J, Yang YX, Guo JY. Protective effect of gan mai da zao decoction in unpredictable chronic mild stress-induced behavioral and biochemical alterations. PHARMACEUTICAL BIOLOGY 2010; 48:1328-1336. [PMID: 20738212 DOI: 10.3109/13880201003789440] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
AIM Growing evidence indicates that the glutamatergic system, especially the abnormalities of glutamate and N-methyl-D-aspartate (NMDA) receptors contribute to the pathophysiology and possibly the pathogenesis of major depressive disorders. This study is to evaluate the effect of gan mai da zao (GMDZ) decoction on glutamate and NMDA receptor in unpredictable chronic mild stress (UCMS) rats. MATERIALS AND METHODS Sucrose preference test and open field test were used to estimate the depressive-like behaviors of UCMS rats. Glutamate levels and NMDA receptor subunits (NR1, NR2A and NR2B) in the frontal cortex and hippocampus were determined by HPLC-FLD and by western-blot respectively. RESULTS 32 days UCMS induced depressive-like behaviors, increased glutamate concentration and decreased NMDA receptor subunits NR2A and NR2B in the frontal cortex and hippocampus of rats. However, NR1 expression remained constant in stressed rats compared with normal. The GMDZ decoction alleviated the depressive-like behavior, decreased glutamate level, and increased expression of NMDA receptor subunit NR2A and NR2B in the frontal cortex and hippocampus of stressed rats. CONCLUSIONS These results suggest that GMDZ treatment reversed chronic unpredictable stress-induced depressive-like behaviors in UCMS rats, possibly via reducing glutamate levels and increasing the NMDA receptor subunits NR2A and NR2B in frontal cortex and hippocampus.
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Affiliation(s)
- Jian-Shu Lou
- Center for Drug Safety Evaluation and Research, Medical College, Zhejiang University, Hangzhou, Republic of China
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22
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Brocardo PDS, Budni J, Lobato KR, Kaster MP, Rodrigues ALS. Antidepressant-like effect of folic acid: Involvement of NMDA receptors and L-arginine-nitric oxide-cyclic guanosine monophosphate pathway. Eur J Pharmacol 2008; 598:37-42. [PMID: 18789921 DOI: 10.1016/j.ejphar.2008.08.033] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2007] [Revised: 08/10/2008] [Accepted: 08/21/2008] [Indexed: 10/21/2022]
Abstract
Antidepressant-like activity of folic acid in forced swimming test and in the tail suspension test was demonstrated previously by our group. In this study we investigated the involvement of N-methyl-d-aspartate (NMDA) receptors and l-arginine-nitric oxide (NO)-cyclic guanosine monophosphate pathway in its antidepressant-like effect in the forced swimming test in mice. The antidepressant-like effect of folic acid (10 nmol/site, i.c.v.) was prevented by the pretreatment of mice with NMDA (0.1 pmol/site, i.c.v.), l-arginine (750 mg/kg, i.p., substrate for nitric oxide synthase), S-nitroso-N-acetyl-penicillamine (SNAP, 25 microg/site, i.c.v, a NO donor) or sildenafil (5 mg/kg, i.p., phosphodiesterase 5 inhibitor). The administration of 7-nitroindazole (25 and 50 mg/kg, i.p., a specific neuronal nitric oxide synthase (nNOS) inhibitor) or methylene blue (20 mg/kg, i.p., direct inhibitor of both nitric oxide synthase and soluble guanylate cyclase) in combination with a sub-effective dose of folic acid (1 nmol/site, i.c.v.) reduced the immobility time in the FST as compared with either drug alone. Together the results suggest that the antidepressant-like effect of folic acid in the forced swimming test is dependent on an inhibition of either NMDA receptors or NO and cGMP synthesis.
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Affiliation(s)
- Patrícia de Souza Brocardo
- Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Campus Universitário, Trindade, 88040-900, Florianópolis-SC, Brazil
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23
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Burbassi S, Cervo L. Stimulation of serotonin2C receptors influences cocaine-seeking behavior in response to drug-associated stimuli in rats. Psychopharmacology (Berl) 2008; 196:15-27. [PMID: 17899022 DOI: 10.1007/s00213-007-0916-7] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2007] [Accepted: 08/08/2007] [Indexed: 12/01/2022]
Abstract
RATIONALE It has been suggested that the increase in serotonin transmission induced by indirect agonists such as fenfluramine and fluoxetine attenuates cue-elicited reinstatement of cocaine-seeking in rats through a 5-HT2C receptor-dependent mechanism. OBJECTIVE We investigated whether Ro 60-0175, a nonselective 5-HT2B-2C agonist, influences cue-elicited reinstatement of cocaine-seeking behavior. We evaluated the 5-HT2C receptor's role in Ro 60-0175 by studying its interaction with SB-242,084, a selective 5-HT2C antagonist. The study also explored whether Ro 60-0175 influences cue-elicited seeking behavior associated with sucrose, a highly palatable nutritive reinforcer. MATERIALS AND METHODS Different groups of free-feeding rats were trained to associate discriminative stimuli (SDs) with the availability of cocaine or a sucrose pellet or no-reward in two-lever operant cages. Cocaine and sucrose pellets were available under an FR1 schedule of reinforcement, and each reinforcer was followed by a 20-s timeout signaled by a cue light coming above the active lever. After extinction of reinforced responding in the absence of cue, the reinforcer-associated stimuli were reintroduced in reinstatement sessions in which reinforcers were withheld. RESULTS Ro 60-0175, at IP doses from 0.1 to 1 mg/kg, dose-dependently reduced cocaine-seeking behavior, while 1 mg/kg had no such effect for the sucrose pellet. Pretreatment with 1 mg/kg SC SB-242,084 completely prevented the effect on cocaine-seeking behavior. CONCLUSIONS These findings, provided they can be extrapolated to abstinent human addicts, suggest therapeutic potential for the selective 5-HT2C agonist in preventing cue-controlled cocaine-seeking and relapse.
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Affiliation(s)
- Silvia Burbassi
- Experimental Psychopharmacology, Department of Neuroscience, Istituto di Ricerche Farmacologiche "Mario Negri", Via La Masa 19, 20156 Milan, Italy
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Abstract
Most neurological and psychiatric disorders involve selective or preferential impairments of neurotransmitter systems. Therefore, studies of functional transmitter pathophysiology in human brain are of unique importance in view of the development of effective, mechanism-based, therapeutic modalities. It is well known that central nervous system functional proteins, including receptors, transporters, ion channels, and enzymes, can exhibit high heterogeneity in terms of structure, function, and pharmacological profile. If the existence of types and subtypes of functional proteins amplifies the possibility of developing selective drugs, such heterogeneity certainly increases the likelihood of interspecies differences. It is therefore essential, before choosing animal models to be used in preclinical pharmacology experimentation, to establish whether functionally corresponding proteins in men and animals also display identical pharmacological profiles. Because of evidence that scaffolding proteins, trafficking between plasma membrane and intracellular pools, phosphorylation and allosteric modulators can affect the function of receptors and transporters, experiments with human clones expressed in host cells where the environment of native receptors is rarely reproduced should be interpreted with caution. Thus, the use of neurosurgically removed fresh human brain tissue samples in which receptors, transporters, ion channels, and enzymes essentially retain their natural environment represents a unique experimental approach to enlarge our understanding of human brain processes and to help in the choice of appropriate animal models. Using this experimental approach, many human brain functional proteins, in particular transmitter receptors, have been characterized in terms of localization, function, and pharmacological properties.
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Affiliation(s)
- Maurizio Raiteri
- Dipartimento di Medicina Sperimentale, Sezione di Farmacologia e Tossicologia, Viale Cembrano 4, 16148 Genova, Italy.
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Guix FX, Uribesalgo I, Coma M, Muñoz FJ. The physiology and pathophysiology of nitric oxide in the brain. Prog Neurobiol 2005; 76:126-52. [PMID: 16115721 DOI: 10.1016/j.pneurobio.2005.06.001] [Citation(s) in RCA: 474] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2005] [Revised: 06/10/2005] [Accepted: 06/14/2005] [Indexed: 12/11/2022]
Abstract
Nitric oxide (NO) is a molecule with pleiotropic effects in different tissues. NO is synthesized by NO synthases (NOS), a family with four major types: endothelial, neuronal, inducible and mitochondrial. They can be found in almost all the tissues and they can even co-exist in the same tissue. NO is a well-known vasorelaxant agent, but it works as a neurotransmitter when produced by neurons and is also involved in defense functions when it is produced by immune and glial cells. NO is thermodynamically unstable and tends to react with other molecules, resulting in the oxidation, nitrosylation or nitration of proteins, with the concomitant effects on many cellular mechanisms. NO intracellular signaling involves the activation of guanylate cyclase but it also interacts with MAPKs, apoptosis-related proteins, and mitochondrial respiratory chain or anti-proliferative molecules. It also plays a role in post-translational modification of proteins and protein degradation by the proteasome. However, under pathophysiological conditions NO has damaging effects. In disorders involving oxidative stress, such as Alzheimer's disease, stroke and Parkinson's disease, NO increases cell damage through the formation of highly reactive peroxynitrite. The paradox of beneficial and damaging effects of NO will be discussed in this review.
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Affiliation(s)
- F X Guix
- Laboratori de Fisiologia Molecular, Unitat de Senyalització Cellular, Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, Carrer Dr. Aiguader, 80, Barcelona 08003, Spain
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Oosthuizen F, Wegener G, Harvey BH. Nitric oxide as inflammatory mediator in post-traumatic stress disorder (PTSD): evidence from an animal model. Neuropsychiatr Dis Treat 2005; 1:109-23. [PMID: 18568056 PMCID: PMC2413191 DOI: 10.2147/nedt.1.2.109.61049] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Post-traumatic stress disorder (PTSD) is a severe anxiety disorder that may develop after experiencing or witnessing a traumatic event. Recent clinical evidence has suggested the involvement of neurodegenerative pathology in the illness, particularly with brain imaging studies revealing a marked reduction in hippocampal volume. Of greater significance is that these anatomical changes appear to be positively correlated with the degree of cognitive deficit noted in these patients. Stress-induced increases in plasma cortisol have been implicated in this apparent atrophy. Although not definitive, clinical studies have observed a marked suppression of plasma cortisol in PTSD. The basis for hippocampal neurodegeneration and cognitive decline therefore remains unclear. Stress and glucocorticoids increase glutamate release, which is recognized as an important mediator of glucocorticoid-induced neurotoxicity. Recent preclinical studies have also noted that glutamate and nitric oxide (NO) play a causal role in anxiety-related behaviors. Because of the prominent role of NO in neuronal toxicity, cellular memory processes, and as a neuromodulator, nitrergic pathways may have an important role in stress-related hippocampal degenerative pathology and cognitive deficits seen in patients with PTSD. This paper reviews the preclinical evidence for involvement of the NO-pathway in PTSD, and emphasizes studies that have addressed these issues using time-dependent sensitization - a putative animal model of PTSD.
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Affiliation(s)
- Frasia Oosthuizen
- School of Pharmacy (Pharmacology), Faculty of Health Sciences, North West University, Potchefstroom, South Africa.
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Kasparov S, Paton J, Wang S, Deuchars J. Nitroxergic Modulation in the NTS. ADVANCES IN VAGAL AFFERENT NEUROBIOLOGY 2005. [DOI: 10.1201/9780203492314.ch9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Pepicelli O, Brescia A, Gherzi E, Raiteri M, Fedele E. GABA(A), but not NMDA, receptors modulate in vivo NO-mediated cGMP synthesis in the rat cerebral cortex. Neuropharmacology 2004; 46:480-9. [PMID: 14975671 DOI: 10.1016/j.neuropharm.2003.10.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2003] [Accepted: 10/14/2003] [Indexed: 10/26/2022]
Abstract
We have investigated the functional relationships between NMDA receptors and the NOS/sGC system in the rat pre-frontal cortex in vivo by microdialysis. cGMP basal levels were sensitive to NOS or sGC inhibitors (L-NARG or ODQ) or NO donors (SNAP) when enzymatic breakdown was blocked by the phosphodiesterase inhibitor IBMX, indicating that basal cGMP production derives, at least in part, from the NOS/sGC pathway activity and that the pre-frontal cortex possesses a very efficient degradation system for cGMP. The glutamate receptor agonist NMDA did not alter extracellular cGMP either in absence or presence of IBMX. cGMP was not augmented when NMDA was co-infused with the NOS substrate L-arginine, the glycine site agonist d-serine or the glutamate receptor agonist AMPA. Interestingly, the selective GABA(A) receptor antagonist bicuculline enhanced cGMP production, revealing that the cortical NOS/sGC system is tonically inhibited by endogenous GABA. However, in the presence of bicuculline, NMDA did not increase extracellular cGMP. In the presence of bicuculline, blockade of 5-HT1/2 receptors, known to inhibit the NMDA/NOS/sGC pathway, with the antagonist methiothepin did not unmask cGMP elevations by NMDA. Thus, it would seem that NMDA receptors do not regulate cortical NOS/sGC activity that, on the other hand, is modulated by endogenous GABA acting at GABA(A) receptors.
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Affiliation(s)
- Olimpia Pepicelli
- Dipartimento di Medicina Sperimentale, Sezione di Farmacologia e Tossicologia, Università di Genova, Viale Cembrano 4, 16148 Genova, Italy
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Graf M, Jakus R, Kantor S, Levay G, Bagdy G. Selective 5-HT1A and 5-HT7 antagonists decrease epileptic activity in the WAG/Rij rat model of absence epilepsy. Neurosci Lett 2004; 359:45-8. [PMID: 15050708 DOI: 10.1016/j.neulet.2004.01.072] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2003] [Revised: 01/27/2004] [Accepted: 01/27/2004] [Indexed: 11/18/2022]
Abstract
Recent studies have provided evidence that activation of 5-HT1A receptors increases epileptic activity in the WAG/Rij rat model of absence epilepsy, and additional data have suggested the involvement of 5-HT7 receptors as well. Therefore, we have tested the effects of the selective 5-HT1A receptor antagonist WAY-100635 and the selective 5-HT7 receptor antagonist SB-258719 on spontaneous epileptic activity. In general, both compounds reduced epileptic activity compared to vehicle. Significant decreases were found in the number of paroxysms and the cumulative and average duration of spike-wave discharges (SWDs), although the time courses of these effects induced by the two compounds were clearly different. These results provide evidence that activation of 5-HT1A and 5-HT7 receptors plays a significant role in regulating SWD activity in this animal model of absence epilepsy.
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Affiliation(s)
- Marton Graf
- Laboratory of Neurochemistry and Experimental Medicine, National Institute of Psychiatry and Neurology, Huvosvolgyi ut 116, H-1021, Budapest, Hungary
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Regina MJ, Winter JC, Rabin RA. Characterization of a novel effect of serotonin 5-HT1A and 5-HT2A receptors: increasing cGMP levels in rat frontal cortex. Neuropharmacology 2004; 45:1041-9. [PMID: 14614947 DOI: 10.1016/s0028-3908(03)00287-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Elucidating the mechanisms of action of hallucinogens has become an increasingly important area of research as their abuse has grown in recent years. Although serotonin receptors appear to play a role in the behavioral effects of the phenethylamine and indoleamine hallucinogens, the signaling pathways activated by these agents are unclear. Here it is shown that administration of serotonin (5-hydroxytryptamine, 5-HT) increased cyclic guanosine monophosphate (cGMP) production in frontal cortical slices of rat brain. The effect of 5-HT was greater than that of N-methyl-D-aspartate (NMDA), a stimulant of cGMP formation in the central nervous system. The 5-HT(2A/2C) receptor phenethylamine agonist, 2,5-dimethoxy-4-methylamphetamine (DOM), increased cGMP content in the slices. Additionally 8-hydroxy-2-(di-n-propylamino)tetralin (DPAT), a 5-(HT1A/7) receptor agonist also increased cGMP production. Stimulation of cGMP formation by DOM was prevented by a 5-HT(2A/2C) receptor antagonist, pirenperone, as well as by a 5-HT2A receptor selective antagonist, MDL100907. A 5-HT2C receptor antagonist, SB242084, did not block the effect of DOM. Stimulation of cGMP production by DPAT was blocked by the 5-HT1A receptor antagonist, WAY100635. Stimulation of cGMP formation by serotonin could be prevented by pirenperone or WAY100635. In summary, activation of serotonin 5-HT1A and 5-HT2A receptors increase brain cGMP levels.
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Affiliation(s)
- Meredith J Regina
- SUNY-Buffalo, Department of Pharmacology and Toxicology, 102 Farber Hall, Buffalo, NY 14214-3000, USA
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Pollandt S, Drephal C, Albrecht D. 8-OH-DPAT suppresses the induction of LTP in brain slices of the rat lateral amygdala. Neuroreport 2003; 14:895-7. [PMID: 12858056 DOI: 10.1097/00001756-200305060-00025] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The effect of 8-OH-DPAT on the induction of long-term potentiation (LTP) in the lateral nucleus of the amygdala was investigated using rat horizontal brain slice preparations. Bath-applied 8-OH-DPAT decreased the field potential amplitudes in a dose-dependent manner. In the lateral amygdala synapses, 8-OH-DPAT significantly suppressed the induction of LTP evoked by a weak theta burst stimulation. This suppression of LTP was also found using a concentration of 8-OH-DPAT, which did not influence the baseline activity significantly. The specific 5-HT(1A) receptor antagonist, WAY 100,635 blocked the inhibitory effect of 8-OH-DPAT on the induction of LTP. The inhibitory effect of 5-HT(1A) receptor stimulation on amygdaloid neuronal plasticity suggests that the amygdala is a site for serotonin to exert its influence on memory of aversive events.
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Affiliation(s)
- Sebastian Pollandt
- Johannes Müller Institute of Physiology, Faculty of Medicine (Charité), Humboldt University, Tucholskystr. 2, 10117 Berlin, Germany
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Koylu EO, Uz T, Manev H, Pogun S. Nitric oxide synthase inhibition suppresses wet dog shakes and augments convulsions in rats. Int J Neurosci 2002; 112:291-300. [PMID: 12187780 DOI: 10.1080/00207450212029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Electrical stimulation of limbic structures, pharmacological interventions, and getting wet induces wet dog shakes (WDS) in rats. WDS are often associated with the occurrence of seizures. In this study, we evaluated the effects of reduced NO production on physiologically (wetting)- or pharmacologically (kainic acid; KA)-induced WDS and KA-triggered seizures. Following wetting, naive and saline-treated rats displayed more WDS than rats treated with NO synthase (NOS) inhibitor, N omega-nitro-L-arginine (L-NA). In another experiment, WDS and seizures were monitored after KA treatment alone or in combination with L-NA. Again, NOS inhibition reduced the number of KA-triggered WDS but augmented the number and severity of seizures. Our results suggest that not only do physiologically- and kainate-induced WDS share a common mechanism that includes NO, but that there is also an antagonism between WDS and convulsions.
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Affiliation(s)
- Ersin O Koylu
- Ege University Center for Brain Research, School of Medicine, Department of Physiology, Izmir, Turkey
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Raymond JR, Mukhin YV, Gelasco A, Turner J, Collinsworth G, Gettys TW, Grewal JS, Garnovskaya MN. Multiplicity of mechanisms of serotonin receptor signal transduction. Pharmacol Ther 2001; 92:179-212. [PMID: 11916537 DOI: 10.1016/s0163-7258(01)00169-3] [Citation(s) in RCA: 331] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The serotonin (5-hydroxytryptamine, 5-HT) receptors have been divided into 7 subfamilies by convention, 6 of which include 13 different genes for G-protein-coupled receptors. Those subfamilies have been characterized by overlapping pharmacological properties, amino acid sequences, gene organization, and second messenger coupling pathways. Post-genomic modifications, such as alternative mRNA splicing or mRNA editing, creates at least 20 more G-protein-coupled 5-HT receptors, such that there are at least 30 distinct 5-HT receptors that signal through G-proteins. This review will focus on what is known about the signaling linkages of the G-protein-linked 5-HT receptors, and will highlight some fascinating new insights into 5-HT receptor signaling.
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Affiliation(s)
- J R Raymond
- The Research Service of the Ralph H. Johnson Veterans Affairs Medical Center, Charleston, SC 29401, USA.
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