1
|
Salmerón AM, Pérez-Fernández C, Abreu AC, Fernández S, Tristán AI, Ruiz-Sobremazas D, Cabré M, Guardia-Escote L, Fernández I, Sánchez-Santed F. Exploring Microbiota-Gut-Brain Axis Biomarkers Linked to Autism Spectrum Disorder in Prenatally Chlorpyrifos-Exposed Fmr1 Knock-Out and Wild-Type Male Rats. Toxicology 2024:153871. [PMID: 38925359 DOI: 10.1016/j.tox.2024.153871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 06/19/2024] [Accepted: 06/21/2024] [Indexed: 06/28/2024]
Abstract
Fmr1 (fragile X messenger ribonucleoprotein 1)-knockout (KO) rats, modeling the human Fragile X Syndrome (FXS), are of particular interest for exploring the ASD-like phenotype in preclinical studies. Gestational exposure to chlorpyrifos (CPF) has been associated with ASD diagnosis in humans and ASD-like behaviors in rodents and linked to the microbiota-gut-brain axis. In this study, we have used both Fmr1-KO and wild-type male rats (F2 generation) at postnatal days (PND) 7 and 40 obtained after F1 pregnant females were randomly exposed to 1mg/kg/mL/day of CPF or vehicle. A nuclear magnetic resonance (NMR) metabolomics approach together with gene expression profiles of these F2 generation rats were employed to analyze different brain regions (such as prefrontal cortex, hippocampus, and cerebellum), whole large intestine (at PND7) and gut content (PND40). The statistical comparison of each matrix spectral profile unveiled tissue-specific metabolic fingerprints. Significant variations in some biomarker levels were detected among brain tissues of different genotypes, including taurine, myo-inositol, and 3-hydroxybutyric acid, and exposure to CPF induced distinct metabolic alterations, particularly in serine and myo-inositol. Additionally, this study provides a set of metabolites associated with gastrointestinal dysfunction in ASD, encompassing several amino acids, choline-derived compounds, bile acids, and sterol molecules. In terms of gene expression, genotype and gestational exposure to CPF had only minimal effects on decarboxylase 2 (gad2) and cholinergic receptor muscarinic 2 (chrm2) genes.
Collapse
Affiliation(s)
- Ana M Salmerón
- Department of Chemistry and Physics, Research Centre CIAIMBITAL, University of Almería, Almería Spain
| | - Cristian Pérez-Fernández
- Department of Psychology and Health Research Centre, Health Research Centre CEINSAUAL, University of Almería, Ctra. Sacramento s/n 04120, Almería Spain
| | - Ana C Abreu
- Department of Chemistry and Physics, Research Centre CIAIMBITAL, University of Almería, Almería Spain.
| | - Silvia Fernández
- Department of Chemistry and Physics, Research Centre CIAIMBITAL, University of Almería, Almería Spain
| | - Ana I Tristán
- Department of Chemistry and Physics, Research Centre CIAIMBITAL, University of Almería, Almería Spain
| | - Diego Ruiz-Sobremazas
- Department of Psychology and Health Research Centre, Health Research Centre CEINSAUAL, University of Almería, Ctra. Sacramento s/n 04120, Almería Spain
| | - María Cabré
- Research Group in Neurobehavior and Health (NEUROLAB) and Department of Biochemistry and Biotechnology, Universitat Rovira i Virgili, Tarragona, Spain
| | - Laia Guardia-Escote
- Research Group in Neurobehavior and Health (NEUROLAB) and Department of Psychology and Research Center for Behavior Assessment (CRAMC), Universitat Rovira i Virgili, Tarragona, Spain
| | - Ignacio Fernández
- Department of Chemistry and Physics, Research Centre CIAIMBITAL, University of Almería, Almería Spain.
| | - Fernando Sánchez-Santed
- Department of Psychology and Health Research Centre, Health Research Centre CEINSAUAL, University of Almería, Ctra. Sacramento s/n 04120, Almería Spain
| |
Collapse
|
2
|
Arjol D, Agüera ADR, Hagen C, Papini MR. Frustrative nonreward: Detailed c-Fos expression patterns in the amygdala after consummatory successive negative contrast. Neurobiol Learn Mem 2024; 213:107942. [PMID: 38815677 DOI: 10.1016/j.nlm.2024.107942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 04/05/2024] [Accepted: 05/27/2024] [Indexed: 06/01/2024]
Abstract
The amygdala has been implicated in frustrative nonreward induced by unexpected reward downshifts, using paradigms like consummatory successive negative contrast (cSNC). However, existing evidence comes from experiments involving the central and basolateral nuclei on a broad level. Moreover, whether the amygdala's involvement in reward downshift requires a cSNC effect (i.e., greater suppression in downshifted animals than in unshifted controls) or just consummatory suppression without a cSNC effect, remains unclear. Three groups were exposed to (1) a large reward disparity leading to a cSNC effect (32-to-2% sucrose), (2) a small reward disparity involving consummatory suppression in the absence of a cSNC effect (8-to-2% sucrose), and (3) an unshifted control (2% sucrose). Brains obtained after the first reward downshift session were processed for c-Fos expression, a protein often used as a marker for neural activation. c-Fos-positive cells were counted in the anterior, medial, and posterior portions (A/P axis) of ten regions of the rat basolateral, central, and medial amygdala. c-Fos expression was higher in 32-to-2% sucrose downshift animals than in the other two groups in four regions: the anterior and the medial lateral basal amygdala, the medial capsular central amygdala, and the anterior anterio-ventral medial amygdala. None of the areas exhibited differential c-Fos expression between the 8-to-2% sucrose downshift and the unshifted conditions. Thus, amygdala activation requires exposure to a substantial reward disparity. This approach has identified, for the first time, specific amygdala areas relevant to understand the cSNC effect, suggesting follow-up experiments aimed at testing the function of these regions in reward downshift.
Collapse
Affiliation(s)
- David Arjol
- Facultad de Psicología, Universidad de Sevilla, Sevilla, Spain
| | | | - Christopher Hagen
- Department of Psychology, Texas Christian University, Fort Worth, TX 76129, USA
| | | |
Collapse
|
3
|
Paliwal NP, Taksande BG, Jain SP, Borikar SP. Possible involvement of GABAergic system on central amygdala Mediated anxiolytic effect of agmatine in rats. Int J Neurosci 2023:1-11. [PMID: 37801395 DOI: 10.1080/00207454.2023.2268262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 10/03/2023] [Indexed: 10/08/2023]
Abstract
OBJECTIVES To study the pharmacological interactions between agmatine and gamma aminobutyric acid (GABA) modulatory agents in the regulation of anxiety-like behavior in rats. MATERIALS AND METHODS Male Wistar rats were treated drugs per se or in combination and 15 min after last injection were subjected to elevated plus-maze (EPM) test. Anxiety-like behavior was evaluated by measuring behavioral conventional readout, open arm activity (duration and/or entries) for 5-minute duration. RESULTS Acute intra-central amygdala (CeA) injection of agmatine (0.1-0.6 μmol/site/rat), muscimol (0.25-1 nmol/site/rat), diazepam (5-20 μg/site/rat) and allopregnanolone (2-8 μg/site/rat) increased open arm entries of the rats in EPM suggesting anxiolytic effect in dose dependent manner. Moreover, the anxiolytic effect at subeffective dose of agmatine (0.1 μmol/site/rat) was potentiated by subeffective dose of muscimol (0.25 nmol/site/rat), diazepam (5 μg/site/rat) and allopregnanolone (4 μg/site/rat). Whereas, pretreatment with GABAA receptor antagonist, bicuculline (10 ng/site/rat) blocked the anxiolytic effect of agmatine and its synergistic effect of agmatine plus muscimol. Similarly, benzodiazepine (BZD) receptor antagonist, flumazenil (15 μg/site/rat) and GABA allosteric modulator antagonist, RO 15-45 13 (10 μg/site/rat) reduced the anxiolytic effect of agmatine, given alone and with diazepam and allopregnanolone, respectively. CONCLUSION These results indicated that anxiolytic effect of agmatine is medicated via GABAergic mechanisms, probably conciliated by the GABAA receptor subtypes. Modulation of interplay between agmatine and GABAA receptor activity might be a pertinent solution for the regulation of anxiety.
Collapse
Affiliation(s)
- Nikhilesh P Paliwal
- Division of Neuroscience, Department of Pharmacology, Shrimati Kishoritai Bhoyar College of Pharmacy, Kamptee, India
| | - Brijesh G Taksande
- Division of Neuroscience, Department of Pharmacology, Shrimati Kishoritai Bhoyar College of Pharmacy, Kamptee, India
| | - Shirish P Jain
- Department of Pharmacology, Rajarshi Shahu College of Pharmacy, Buldana, India
| | - Sachin P Borikar
- Department of Pharmacology, Rajarshi Shahu College of Pharmacy, Buldana, India
| |
Collapse
|
4
|
Tongta S, Daendee S, Kalandakanond-Thongsong S. Anxiety-like behavior and GABAergic system in ovariectomized rats exposed to chronic mild stress. Physiol Behav 2023; 258:114014. [PMID: 36328075 DOI: 10.1016/j.physbeh.2022.114014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 10/14/2022] [Accepted: 10/27/2022] [Indexed: 11/06/2022]
Abstract
Stress or low level of estrogen could promote anxiety and depression; thus, it is of interest to investigate the combined effect of mild stress and the lack of estrogen on mental disorders by utilizing an animal model. This study was conducted to assess anxiety- and depressive- like behaviors in ovariectomized (Ovx) rats exposed to chronic mild stress (CMS) and determine the alteration in gamma-aminobutyric acid (GABA)-related transmission. Ovx rats were randomly assigned into four groups: (1) estrogen replacement (E2-NoCMS), (2) estrogen replacement and exposure to CMS (E2-CMS), (3) vehicle (VEH-NoCMS), and (4) vehicle and exposure to CMS (VEH-CMS). Following 4-week CMS, VEH groups (VEH-NoCMS and VEH-CMS) showed a similar level of anxiety-like behavior in elevated T-maze, whereas E2-CMS, VEH-NoCMS and VEH-CMS showed anxiety-like behavior in open field. The depressive-like behavior in the force swimming test tended to be affected by estrogen deprivation than CMS. The alteration of the GABAergic system as determined from the GABA level and mRNA expression of GABA-related transmission (i.e., glutamic acid decarboxylase, GABA transporter and GABAA subunits) showed that the GABA level in the amygdala and frontal cortex was affected by CMS. For mRNA expression, the mRNA profile in the amygdala and hippocampus of VEH-NoCMS and E2-CMS was the same but different from those of VEH-NoCMS and E2-CMS. In addition, compared with E2-NoCMS, the mRNA profile in the frontal cortex was similar in VEH-NoCMS, E2-CMS, and VEH-CMS. These findings indicated that the underlying mechanism of the GABAergic system was differently modified, although VEH-NoCMS and VEH-CMS showed anxiety-like behavior. The findings of this study may provide a comprehensive understanding of the modulation of the GABAergic system during estrogen deprivation under CMS, as observed in menopausal women who were daily exposed to stress.
Collapse
Affiliation(s)
- Sushawadee Tongta
- Department of Veterinary Physiology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Suwaporn Daendee
- College of Medicine and Public Health, Ubon Ratchathani University, Ubon Ratchathani 34190, Thailand
| | | |
Collapse
|
5
|
Perez-Fernandez C, Matamala Montoya M, Morales-Navas M, Guardia-Escote L, Cabré M, Colomina MT, Giménez E, Sánchez-Santed F. Influence of Gestational Chlorpyrifos Exposure on ASD-like Behaviors in an fmr1-KO Rat Model. Mol Neurobiol 2022; 59:5835-5855. [PMID: 35802248 DOI: 10.1007/s12035-022-02933-0] [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: 03/07/2022] [Accepted: 06/17/2022] [Indexed: 11/26/2022]
Abstract
Based on previous reports, exposure to pesticides could be linked to the prevalence increase of autism spectrum disorders (ASD). Gestational exposure to chlorpyrifos (CPF) has been associated with ASD diagnosis in humans and ASD-like behaviors in rodents. However, ASD severity degree results from the complex relationship between genetic background and environmental factors. Thus, animals with a genetic vulnerability and prenatally exposed to CPF could have a more severe ASD-like phenotype. Fragile X syndrome is one of the most common monogenic causes of ASD, characterized by a mutation in the X chromosome which alters the expression of the fragile X mental retardation protein (FMRP). Based on this, some fmr1 knockout (KO) rodent models have been developed to study the physiological and genetic basis of ASD. Both fmr1-KO and wild-type male rats (F2 generation) were used in the present study. F1 pregnant females were randomly exposed to 1 mg/kg/mL/day of CPF (s.c.) from GD12.5-15.5 or vehicle. Different behavioral, developmental, and molecular variables were analyzed in F2 males. KO rats were heavier, emitted altered USVs, were socially inefficient, reacted more to a novel stimulus, were hyperactive when exploring a new context, but hypoactive when exploring anxiety-inducing environments, and had an upregulated hippocampal expression of the grin2c gene. When exposed to low doses of CPF during gestation, these KO rats showed decreased climbing capacity, dysfunctional social interaction, and increased hippocampal expression for kcc1 and 5ht2c genes. Gestational CPF exposure increased the ASD-like phenotype in those animals with a genetic vulnerability, although its effect was less generalized than expected. It is the first time that this additive effect of CPF exposure and the fmr1-KO genetic vulnerability model is explored concerning social traits or any other behavior.
Collapse
Affiliation(s)
- Cristian Perez-Fernandez
- Department of Psychology and Health Research Center (CEINSA), Laboratory of Psychobiology, University of Almería CeiA3, Carretera de Sacramento s/n, La Cañada de San Urbano, 04120, Almería, Spain
| | - María Matamala Montoya
- Biomolecular Mass Spectrometry and Proteomics Group, Faculty of Science, Utrecht University, 3584 CS, Utrecht, The Netherlands
| | - Miguel Morales-Navas
- Department of Psychology and Health Research Center (CEINSA), Laboratory of Psychobiology, University of Almería CeiA3, Carretera de Sacramento s/n, La Cañada de San Urbano, 04120, Almería, Spain
| | - Laia Guardia-Escote
- Research in Neurobehavior and Health (NEUROLAB), Universitat Rovira I Virgili, 43007, Tarragona, Spain
- Department of Psychology and Research Center for Behavior Assessment (CRAMC), Universitat Rovira I Virgili, Campus Sescelades, 43007, Tarragona, Spain
| | - María Cabré
- Research in Neurobehavior and Health (NEUROLAB), Universitat Rovira I Virgili, 43007, Tarragona, Spain
- Department of Biochemistry and Biotechnology, Universitat Rovira I Virgili, 43007, Tarragona, Spain
| | - María Teresa Colomina
- Research in Neurobehavior and Health (NEUROLAB), Universitat Rovira I Virgili, 43007, Tarragona, Spain
- Department of Psychology and Research Center for Behavior Assessment (CRAMC), Universitat Rovira I Virgili, Campus Sescelades, 43007, Tarragona, Spain
| | - Estela Giménez
- Department of Biology and Geology, University of Almería, Ctra. Sacramento, s/n, 04120, Almería, Spain
| | - Fernando Sánchez-Santed
- Department of Psychology and Health Research Center (CEINSA), Laboratory of Psychobiology, University of Almería CeiA3, Carretera de Sacramento s/n, La Cañada de San Urbano, 04120, Almería, Spain.
| |
Collapse
|
6
|
Castellano D, Shepard RD, Lu W. Looking for Novelty in an "Old" Receptor: Recent Advances Toward Our Understanding of GABA ARs and Their Implications in Receptor Pharmacology. Front Neurosci 2021; 14:616298. [PMID: 33519367 PMCID: PMC7841293 DOI: 10.3389/fnins.2020.616298] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Accepted: 12/14/2020] [Indexed: 12/16/2022] Open
Abstract
Diverse populations of GABAA receptors (GABAARs) throughout the brain mediate fast inhibitory transmission and are modulated by various endogenous ligands and therapeutic drugs. Deficits in GABAAR signaling underlie the pathophysiology behind neurological and neuropsychiatric disorders such as epilepsy, anxiety, and depression. Pharmacological intervention for these disorders relies on several drug classes that target GABAARs, such as benzodiazepines and more recently neurosteroids. It has been widely demonstrated that subunit composition and receptor stoichiometry impact the biophysical and pharmacological properties of GABAARs. However, current GABAAR-targeting drugs have limited subunit selectivity and produce their therapeutic effects concomitantly with undesired side effects. Therefore, there is still a need to develop more selective GABAAR pharmaceuticals, as well as evaluate the potential for developing next-generation drugs that can target accessory proteins associated with native GABAARs. In this review, we briefly discuss the effects of benzodiazepines and neurosteroids on GABAARs, their use as therapeutics, and some of the pitfalls associated with their adverse side effects. We also discuss recent advances toward understanding the structure, function, and pharmacology of GABAARs with a focus on benzodiazepines and neurosteroids, as well as newly identified transmembrane proteins that modulate GABAARs.
Collapse
Affiliation(s)
- David Castellano
- Synapse and Neural Circuit Research Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
| | - Ryan David Shepard
- Synapse and Neural Circuit Research Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
| | - Wei Lu
- Synapse and Neural Circuit Research Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
| |
Collapse
|
7
|
Griessner J, Pasieka M, Böhm V, Grössl F, Kaczanowska J, Pliota P, Kargl D, Werner B, Kaouane N, Strobelt S, Kreitz S, Hess A, Haubensak W. Central amygdala circuit dynamics underlying the benzodiazepine anxiolytic effect. Mol Psychiatry 2021; 26:534-544. [PMID: 30504824 PMCID: PMC6411154 DOI: 10.1038/s41380-018-0310-3] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 10/27/2018] [Accepted: 11/12/2018] [Indexed: 11/09/2022]
Abstract
Benzodiazepines (BZDs) have been a standard treatment for anxiety disorders for decades, but the neuronal circuit interactions mediating their anxiolytic effect remain largely unknown. Here, we find that systemic BZDs modulate central amygdala (CEA) microcircuit activity to gate amygdala output. Combining connectome data with immediate early gene (IEG) activation maps, we identified the CEA as a primary site for diazepam (DZP) anxiolytic action. Deep brain calcium imaging revealed that brain-wide DZP interactions shifted neuronal activity in CEA microcircuits. Chemogenetic silencing showed that PKCδ+/SST- neurons in the lateral CEA (CEAl) are necessary and sufficient to induce the DZP anxiolytic effect. We propose that BZDs block the relay of aversive signals through the CEA, in part by local binding to CEAl SST+/PKCδ- neurons and reshaping intra-CEA circuit dynamics. This work delineates a strategy to identify biomedically relevant circuit interactions of clinical drugs and highlights the critical role for CEA circuitry in the pathophysiology of anxiety.
Collapse
Affiliation(s)
- Johannes Griessner
- grid.14826.390000 0000 9799 657XResearch Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030 Vienna, Austria
| | - Manuel Pasieka
- grid.473822.8Bioinformatics and Scientific Computing, Vienna Biocenter (VBC), Dr. Bohr Gasse 3, 1030 Vienna, Austria
| | - Vincent Böhm
- grid.14826.390000 0000 9799 657XResearch Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030 Vienna, Austria
| | - Florian Grössl
- grid.14826.390000 0000 9799 657XResearch Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030 Vienna, Austria
| | - Joanna Kaczanowska
- grid.14826.390000 0000 9799 657XResearch Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030 Vienna, Austria
| | - Pinelopi Pliota
- grid.14826.390000 0000 9799 657XResearch Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030 Vienna, Austria
| | - Dominic Kargl
- grid.14826.390000 0000 9799 657XResearch Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030 Vienna, Austria
| | - Barbara Werner
- grid.14826.390000 0000 9799 657XResearch Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030 Vienna, Austria
| | - Nadia Kaouane
- grid.14826.390000 0000 9799 657XResearch Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030 Vienna, Austria
| | - Sandra Strobelt
- grid.5330.50000 0001 2107 3311Institute of Experimental and Clinical Pharmacology and Toxicology, Friedrich-Alexander University Erlangen-Nuremberg, Fahrstrasse 17, 91054 Erlangen, Germany
| | - Silke Kreitz
- grid.5330.50000 0001 2107 3311Institute of Experimental and Clinical Pharmacology and Toxicology, Friedrich-Alexander University Erlangen-Nuremberg, Fahrstrasse 17, 91054 Erlangen, Germany
| | - Andreas Hess
- grid.5330.50000 0001 2107 3311Institute of Experimental and Clinical Pharmacology and Toxicology, Friedrich-Alexander University Erlangen-Nuremberg, Fahrstrasse 17, 91054 Erlangen, Germany
| | - Wulf Haubensak
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030, Vienna, Austria.
| |
Collapse
|
8
|
Perez-Fernandez C, Morales-Navas M, Guardia-Escote L, Colomina MT, Giménez E, Sánchez-Santed F. Postnatal exposure to low doses of Chlorpyrifos induces long-term effects on 5C-SRTT learning and performance, cholinergic and GABAergic systems and BDNF expression. Exp Neurol 2020; 330:113356. [DOI: 10.1016/j.expneurol.2020.113356] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 04/13/2020] [Accepted: 05/04/2020] [Indexed: 12/19/2022]
|
9
|
Perez-Fernandez C, Morales-Navas M, Guardia-Escote L, Garrido-Cárdenas JA, Colomina MT, Giménez E, Sánchez-Santed F. Long-term effects of low doses of Chlorpyrifos exposure at the preweaning developmental stage: A locomotor, pharmacological, brain gene expression and gut microbiome analysis. Food Chem Toxicol 2020; 135:110865. [DOI: 10.1016/j.fct.2019.110865] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 09/05/2019] [Accepted: 09/30/2019] [Indexed: 12/26/2022]
|
10
|
Developmental Changes in Serotonergic Modulation of GABAergic Synaptic Transmission and Postsynaptic GABA A Receptor Composition in the Cerebellar Nuclei. THE CEREBELLUM 2019; 17:346-358. [PMID: 29349630 DOI: 10.1007/s12311-018-0922-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Outputs from the cerebellar nuclei (CN) are important for generating and controlling movement. The activity of CN neurons is controlled not only by excitatory inputs from mossy and climbing fibers and by γ-aminobutyric acid (GABA)-based inhibitory transmission from Purkinje cells in the cerebellar cortex but is also modulated by inputs from other brain regions, including serotonergic fibers that originate in the dorsal raphe nuclei. We examined the modulatory effects of serotonin (5-HT) on GABAergic synapses during development, using rat cerebellar slices. As previously reported, 5-HT presynaptically decreased the amplitudes of stimulation-evoked inhibitory postsynaptic currents (IPSCs) in CN neurons, with this effect being stronger in slices from younger animals (postnatal days [P] 11-13) than in slices from older animals (P19-21). GABA release probabilities accordingly exhibited significant decreases from P11-13 to P19-21. Although there was a strong correlation between the GABA release probability and the magnitude of 5-HT-induced inhibition, manipulating the release probability by changing extracellular Ca2+ concentrations failed to control the extent of 5-HT-induced inhibition. We also found that the IPSCs exhibited slower kinetics at P11-13 than at P19-21. Pharmacological and molecular biological tests revealed that IPSC kinetics were largely determined by the prevalence of α1 subunits within GABAA receptors. In summary, pre- and postsynaptic developmental changes in serotonergic modulation and GABAergic synaptic transmission occur during the second to third postnatal weeks and may significantly contribute to the formation of normal adult cerebellar function.
Collapse
|
11
|
Meis S, Endres T, Munsch T, Lessmann V. Presynaptic Regulation of Tonic Inhibition by Neuromodulatory Transmitters in the Basal Amygdala. Mol Neurobiol 2018; 55:8509-8521. [PMID: 29560580 DOI: 10.1007/s12035-018-0984-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 02/28/2018] [Indexed: 01/23/2023]
Abstract
Tonic inhibition mediated by ambient levels of GABA that activate extrasynaptic GABAA receptors emerges as an essential factor that tunes neuronal network excitability in vitro and shapes behavioral responses in vivo. To address the role of neuromodulatory transmitter systems on this type of inhibition, we employed patch clamp recordings in mouse amygdala slice preparations. Our results show that the current amplitude of tonic inhibition (Itonic) in projection neurons of the basal amygdala (BA) is increased by preincubation with the neurosteroid THDOC, while the benzodiazepine diazepam is ineffective. This suggests involvement of THDOC sensitive δ subunit containing GABAA receptors in mediating tonic inhibition. Moreover, we provide evidence that the neuromodulatory transmitters NE, 5HT, and ACh strongly enhance spontaneous IPSCs as well as Itonic in the BA. As the increase in frequency, amplitude, and charge of sIPSCs by these neuromodulatory transmitters strongly correlated with the amplitude of Itonic, we conclude that spill-over of synaptic GABA leads to activation of Itonic and thereby to dampening of amygdala excitability. Since local injection of THDOC, as a positive modulator of tonic inhibition, into the BA interfered with the expression of contextual fear memory, our results point to a prominent role of Itonic in fear learning.
Collapse
Affiliation(s)
- S Meis
- Institut für Physiologie, Otto-von-Guericke-Universität, Leipziger Str. 44, D-39120, Magdeburg, Germany. .,Center for Behavioral Brain Sciences, Magdeburg, Germany.
| | - T Endres
- Institut für Physiologie, Otto-von-Guericke-Universität, Leipziger Str. 44, D-39120, Magdeburg, Germany
| | - T Munsch
- Institut für Physiologie, Otto-von-Guericke-Universität, Leipziger Str. 44, D-39120, Magdeburg, Germany.,Center for Behavioral Brain Sciences, Magdeburg, Germany
| | - V Lessmann
- Institut für Physiologie, Otto-von-Guericke-Universität, Leipziger Str. 44, D-39120, Magdeburg, Germany. .,Center for Behavioral Brain Sciences, Magdeburg, Germany.
| |
Collapse
|
12
|
Stefanits H, Milenkovic I, Mahr N, Pataraia E, Hainfellner JA, Kovacs GG, Sieghart W, Yilmazer-Hanke D, Czech T. GABAAreceptor subunits in the human amygdala and hippocampus: Immunohistochemical distribution of 7 subunits. J Comp Neurol 2017; 526:324-348. [DOI: 10.1002/cne.24337] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 09/12/2017] [Accepted: 09/19/2017] [Indexed: 12/18/2022]
Affiliation(s)
- Harald Stefanits
- Department of Neurosurgery; Medical University of Vienna; Vienna Austria
- Institute of Neurology, Medical University of Vienna; Vienna Austria
| | - Ivan Milenkovic
- Department of Clinical Neurology; Medical University of Vienna; Vienna Austria
| | - Nina Mahr
- Department of Neurosurgery; Medical University of Vienna; Vienna Austria
| | - Ekaterina Pataraia
- Department of Clinical Neurology; Medical University of Vienna; Vienna Austria
| | | | - Gabor G. Kovacs
- Institute of Neurology, Medical University of Vienna; Vienna Austria
| | - Werner Sieghart
- Center for Brain Research, Department of Molecular Neurosciences; Medical University of Vienna; Vienna Austria
| | - Deniz Yilmazer-Hanke
- Clinical Neuroanatomy, Neurology Department, Medical Faculty; Ulm University; Ulm Germany
| | - Thomas Czech
- Department of Neurosurgery; Medical University of Vienna; Vienna Austria
| |
Collapse
|
13
|
Novel Molecule Exhibiting Selective Affinity for GABA A Receptor Subtypes. Sci Rep 2017; 7:6230. [PMID: 28740086 PMCID: PMC5524711 DOI: 10.1038/s41598-017-05966-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 06/06/2017] [Indexed: 01/06/2023] Open
Abstract
Aminoquinoline derivatives were evaluated against a panel of receptors/channels/transporters in radioligand binding experiments. One of these derivatives (DCUK-OEt) displayed micromolar affinity for brain γ-aminobutyric acid type A (GABAA) receptors. DCUK-OEt was shown to be a positive allosteric modulator (PAM) of GABA currents with α1β2γ2, α1β3γ2, α5β3γ2 and α1β3δ GABAA receptors, while having no significant PAM effect on αβ receptors or α1β1γ2, α1β2γ1, α4β3γ2 or α4β3δ receptors. DCUK-OEt modulation of α1β2γ2 GABAA receptors was not blocked by flumazenil. The subunit requirements for DCUK-OEt actions distinguished DCUK-OEt from other currently known modulators of GABA function (e.g., anesthetics, neurosteroids or ethanol). Simulated docking of DCUK-OEt at the GABAA receptor suggested that its binding site may be at the α + β- subunit interface. In slices of the central amygdala, DCUK-OEt acted primarily on extrasynaptic GABAA receptors containing the α1 subunit and generated increases in extrasynaptic “tonic” current with no significant effect on phasic responses to GABA. DCUK-OEt is a novel chemical structure acting as a PAM at particular GABAA receptors. Given that neurons in the central amygdala responding to DCUK-OEt were recently identified as relevant for alcohol dependence, DCUK-OEt should be further evaluated for the treatment of alcoholism.
Collapse
|
14
|
Han M, Chang J, Kim J. Loss of divalent metal transporter 1 function promotes brain copper accumulation and increases impulsivity. J Neurochem 2016; 138:918-28. [PMID: 27331785 DOI: 10.1111/jnc.13717] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 06/08/2016] [Accepted: 06/09/2016] [Indexed: 12/20/2022]
Abstract
The divalent metal transporter 1 (DMT1) is a major iron transporter required for iron absorption and erythropoiesis. Loss of DMT1 function results in microcytic anemia. While iron plays an important role in neural function, the behavioral consequences of DMT1 deficiency are largely unexplored. The goal of this study was to define the neurobehavioral and neurochemical phenotypes of homozygous Belgrade (b/b) rats that carry DMT1 mutation and explore potential mechanisms of these phenotypes. The b/b rats (11-12 weeks old) and their healthy littermate heterozygous (+/b) Belgrade rats were subject to elevated plus maze tasks. The b/b rats spent more time in open arms, entered open arms more frequently and traveled more distance in the maze than +/b controls, suggesting increased impulsivity. Impaired emotional behavior was associated with down-regulation of GABA in the hippocampus in b/b rats. Also, b/b rats showed increased GABAA receptor α1 and GABA transporter, indicating altered GABAergic function. Furthermore, metal analysis revealed that b/b rats have decreased total iron, but normal non-heme iron, in the brain. Interestingly, b/b rats exhibited unusually high copper levels in most brain regions, including striatum and hippocampus. Quantitative PCR analysis showed that both copper importer copper transporter 1 and exporter copper-transporting ATPase 1 were up-regulated in the hippocampus from b/b rats. Finally, b/b rats exhibited increased 8-isoprostane levels and decreased glutathione/glutathione disulfide ratio in the hippocampus, reflecting elevated oxidative stress. Combined, our results suggest that copper loading in DMT1 deficiency could induce oxidative stress and impair GABA metabolism, which promote impulsivity-like behavior. Iron-copper model: Mutations in the divalent metal transporter 1 (DMT1) decrease body iron status and up-regulate copper absorption, which leads to copper loading in the brain and consequently increases metal-induced oxidative stress. This event disrupts GABAergic neurotransmission and promotes impulsivity-like behavior. Our model provides better understanding of physiological risks associated with imbalanced metal metabolism in mental function and, more specifically, the interactions with GABA and redox control in the treatment of emotional disorders.
Collapse
Affiliation(s)
- Murui Han
- Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts, USA
| | - JuOae Chang
- Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts, USA
| | - Jonghan Kim
- Department of Pharmaceutical Sciences, Northeastern University, Boston, Massachusetts, USA.
| |
Collapse
|
15
|
Central amygdalar nucleus treated with orexin neuropeptides evoke differing feeding and grooming responses in the hamster. J Neurol Sci 2015; 351:46-51. [PMID: 25732800 DOI: 10.1016/j.jns.2015.02.030] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 01/27/2015] [Accepted: 02/16/2015] [Indexed: 01/23/2023]
Abstract
Interaction of the orexinergic (ORXergic) neuronal system with the excitatory (glutamate, l-Glu) or the inhibitory (GABA) neurosignaling complexes evokes major homeostatic physiological events. In this study, effects of the two ORXergic neuropeptides (ORX-A/B) on their receptor (ORX-2R) expression changes were correlated to feeding and grooming actions of the hibernating hamster (Mesocricetus auratus). Infusion of the central amygdala nucleus (CeA) with ORX-A caused hamsters to consume notable quantities of food, while ORX-B accounted for a moderate increase. Interestingly the latter neuropeptide was responsible for greater frequencies of grooming with respect to both controls and the hamsters treated with ORX-A. These distinct behavioral changes turned out to be even greater in the presence of l-Glu agonist (NMDA) while the α1 GABAA receptor agonist (zolpidem, Zol) greatly reduced ORX-A-dependent feeding bouts. Moreover, ORX-A+NMDA mainly promoted greater ORX-2R expression levels with respect to ORX-A-treated hamsters while ORX-B+Zol was instead largely responsible for a down-regulatory trend. Overall, these features point to CeA ORX-2R sites as key sensory limbic elements capable of regulating eating and grooming responses, which may provide useful insights regarding the type of molecular mechanism(s) operating during feeding bouts.
Collapse
|
16
|
Blednov YA, Benavidez JM, Black M, Leiter CR, Osterndorff-Kahanek E, Johnson D, Borghese CM, Hanrahan JR, Johnston GAR, Chebib M, Harris RA. GABAA receptors containing ρ1 subunits contribute to in vivo effects of ethanol in mice. PLoS One 2014; 9:e85525. [PMID: 24454882 PMCID: PMC3894180 DOI: 10.1371/journal.pone.0085525] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Accepted: 11/27/2013] [Indexed: 11/29/2022] Open
Abstract
GABAA receptors consisting of ρ1, ρ2, or ρ3 subunits in homo- or hetero-pentamers have been studied mainly in retina but are detected in many brain regions. Receptors formed from ρ1 are inhibited by low ethanol concentrations, and family-based association analyses have linked ρ subunit genes with alcohol dependence. We determined if genetic deletion of ρ1 in mice altered in vivo ethanol effects. Null mutant male mice showed reduced ethanol consumption and preference in a two-bottle choice test with no differences in preference for saccharin or quinine. Null mutant mice of both sexes demonstrated longer duration of ethanol-induced loss of righting reflex (LORR), and males were more sensitive to ethanol-induced motor sedation. In contrast, ρ1 null mice showed faster recovery from acute motor incoordination produced by ethanol. Null mutant females were less sensitive to ethanol-induced development of conditioned taste aversion. Measurement of mRNA levels in cerebellum showed that deletion of ρ1 did not change expression of ρ2, α2, or α6 GABAA receptor subunits. (S)-4-amino-cyclopent-1-enyl butylphosphinic acid (“ρ1” antagonist), when administered to wild type mice, mimicked the changes that ethanol induced in ρ1 null mice (LORR and rotarod tests), but the ρ1 antagonist did not produce these effects in ρ1 null mice. In contrast, (R)-4-amino-cyclopent-1-enyl butylphosphinic acid (“ρ2” antagonist) did not change ethanol actions in wild type but produced effects in mice lacking ρ1 that were opposite of the effects of deleting (or inhibiting) ρ1. These results suggest that ρ1 has a predominant role in two in vivo effects of ethanol, and a role for ρ2 may be revealed when ρ1 is deleted. We also found that ethanol produces similar inhibition of function of recombinant ρ1 and ρ2 receptors. These data indicate that ethanol action on GABAA receptors containing ρ1/ρ2 subunits may be important for specific effects of ethanol in vivo.
Collapse
Affiliation(s)
- Yuri A. Blednov
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, Texas, United States of America
| | - Jillian M. Benavidez
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, Texas, United States of America
| | - Mendy Black
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, Texas, United States of America
| | - Courtney R. Leiter
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, Texas, United States of America
| | - Elizabeth Osterndorff-Kahanek
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, Texas, United States of America
| | - David Johnson
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, Texas, United States of America
| | - Cecilia M. Borghese
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, Texas, United States of America
| | - Jane R. Hanrahan
- Faculty of Pharmacy, The University of Sydney, Sydney NSW, Australia
| | | | - Mary Chebib
- Faculty of Pharmacy, The University of Sydney, Sydney NSW, Australia
| | - R. Adron Harris
- Waggoner Center for Alcohol and Addiction Research, The University of Texas at Austin, Austin, Texas, United States of America
- * E-mail:
| |
Collapse
|
17
|
Skórzewska A, Lehner M, Wisłowska-Stanek A, Krząścik P, Ziemba A, Płaźnik A. The effect of chronic administration of corticosterone on anxiety- and depression-like behavior and the expression of GABA-A receptor alpha-2 subunits in brain structures of low- and high-anxiety rats. Horm Behav 2014; 65:6-13. [PMID: 24200620 DOI: 10.1016/j.yhbeh.2013.10.011] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 09/10/2013] [Accepted: 10/26/2013] [Indexed: 11/29/2022]
Abstract
The aim of this study was to examine changes in rat emotional behavior and determine differences in the expression of GABA-A receptor alpha-2 subunits in brain structures of low- (LR) and high-anxiety (HR) rats after the repeated corticosterone administration. The animals were divided into LR and HR groups based on the duration of their conditioned freezing in a contextual fear test. Repeated daily administration of corticosterone (20 mg/kg) for 21 days decreased activity in a forced swim test, reduced body weight and decreased prefrontal cortex corticosterone concentration in both the LR and HR groups. These effects of corticosterone administration were stronger in the HR group in comparison with the appropriate control group, and compared to LR treated and LR control animals. Moreover, in the HR group, chronic corticosterone administration increased anxiety-like behavior in the open field and elevated plus maze tests. The behavioral effects in HR rats were accompanied by a decrease in alpha-2 subunit density in the medial prefrontal cortex (prelimbic cortex and frontal association cortex) and by an increase in the expression of alpha-2 subunits in the basolateral amygdala. These studies have shown that HR rats are more susceptible to anxiogenic and depressive effects of chronic corticosterone administration, which are associated with modification of GABA-A receptor function in the medial prefrontal cortex and basolateral amygdala. The current data may help to better understand the neurobiological mechanisms responsible for individual differences in changes in mood and emotions induced by repeated administration of high doses of glucocorticoids or by elevated levels of these hormones associated with chronic stress or affective pathology.
Collapse
Affiliation(s)
- Anna Skórzewska
- Department of Neurochemistry, Institute of Psychiatry and Neurology, 9 Sobieskiego Street, 02-957 Warsaw, Poland.
| | - Małgorzata Lehner
- Department of Neurochemistry, Institute of Psychiatry and Neurology, 9 Sobieskiego Street, 02-957 Warsaw, Poland
| | - Aleksandra Wisłowska-Stanek
- Department of Experimental and Clinical Pharmacology, Medical University, 26/28 Krakowskie Przedmieście Street, 00-927 Warsaw, Poland
| | - Paweł Krząścik
- Department of Experimental and Clinical Pharmacology, Medical University, 26/28 Krakowskie Przedmieście Street, 00-927 Warsaw, Poland
| | - Andrzej Ziemba
- Department of Applied Physiology, Mossakowski Medical Research Centre Polish Academy of Science, 5 Pawinskiego Street, 02-106 Warsaw, Poland
| | - Adam Płaźnik
- Department of Neurochemistry, Institute of Psychiatry and Neurology, 9 Sobieskiego Street, 02-957 Warsaw, Poland; Department of Experimental and Clinical Pharmacology, Medical University, 26/28 Krakowskie Przedmieście Street, 00-927 Warsaw, Poland
| |
Collapse
|
18
|
Changes in the brain expression of alpha-2 subunits of the GABA-A receptor after chronic restraint stress in low- and high-anxiety rats. Behav Brain Res 2013; 253:337-45. [PMID: 23916758 DOI: 10.1016/j.bbr.2013.07.042] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 07/19/2013] [Accepted: 07/23/2013] [Indexed: 01/02/2023]
Abstract
This study assessed the mechanisms underlying the behavioral differences between high- (HR) and low-anxiety (LR) rats selected for their behavior in the contextual fear test (i.e., the duration of the freezing response was used as a discriminating variable). Rats were subjected to chronic restraint stress (21 days, 3h daily). We found that in the HR group, chronic restraint stress decreased rat activity in the Porsolt test and reduced the concentration of corticosterone in the prefrontal cortex. The behavioral changes were accompanied by a lower expression of alpha-2 GABA-A receptor subunits in the secondary motor cortex (M2 area) and in the dentate gyrus of the hippocampus (DG) compared to LR restraint animals. Moreover, restraint stress increased the density of alpha-2 GABA-A subunits in the basolateral amygdala (BLA) in HR rats and decreased the expression of these subunits in the DG and M2 areas compared to the HR control group. The present results suggest that, in HR rats exposed to chronic restraint stress, the function of hippocampal and cortical GABAergic neurotransmission is attenuated and that this effect could have important influences on the functioning of the hypothalamic-pituitary-adrenal axis and on depressive symptoms.
Collapse
|
19
|
Rosas-Arellano A, Machuca-Parra AI, Reyes-Haro D, Miledi R, Martínez-Torres A. Expression of GABAρ receptors in the neostriatum: localization in aspiny, medium spiny neurons and GFAP-positive cells. J Neurochem 2012; 122:900-10. [PMID: 22168837 DOI: 10.1111/j.1471-4159.2011.07621.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
GABAergic transmission in the neostriatum plays a central role in motor coordination, in which a plethora of GABA-A receptor subunits combine to modulate neural inhibition. GABAρ receptors were originally described in the mammalian retina. These receptors possess special electrophysiological and pharmacological properties, forming a characteristic class of ionotropic receptors. In previous studies, we suggested that GABAρ receptors are expressed in the neostriatum, and in this report we show that they are indeed present in all the calretinin-positive interneurons of the neostriatum. In addition, they are located in calbindin-positive interneurons and projection neurons that express the dopamine D(2) receptor. GABAρ receptors were also located in 30% of the glial fibrillary acidic protein-positive cells, and may therefore also contribute to gliotransmission. Quantitative reverse transcription-PCR suggested that the mRNAs of this receptor do not express as much as in the retina, and that GABAρ2 is more abundant than GABAρ1. Electrophysiological recordings in brain slices provided evidence of neurons expressing a cis-4-aminocrotonic acid-activated, 1,2,5,6-tetrahydropyridine-4-yl methylphosphinic acid-sensitive ionotropic GABA receptor, indicating the presence of functional GABAρ receptors in the neostriatum. Finally, electron-microscopy and immunogold located the receptors mainly in perisynaptic as well as in extrasynaptic sites. All these observations reinforce the importance of GABAρ receptors in the neostriatum and contribute to the diversity of inhibitory regulation in this area.
Collapse
Affiliation(s)
- Abraham Rosas-Arellano
- Departamento de Neurobiología Celular y Molecular, Universidad Nacional Autónoma de México, Instituto de Neurobiología, Campus Juriquilla, Querétaro, Mexico
| | | | | | | | | |
Collapse
|
20
|
Martínez-Delgado G, Estrada-Mondragón A, Miledi R, Martínez-Torres A. An Update on GABAρ Receptors. Curr Neuropharmacol 2011; 8:422-33. [PMID: 21629448 PMCID: PMC3080597 DOI: 10.2174/157015910793358141] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2009] [Revised: 04/08/2010] [Accepted: 06/21/2010] [Indexed: 01/29/2023] Open
Abstract
The present review discusses the functional and molecular diversity of GABAρ receptors. These receptors were originally described in the mammalian retina, and their functional role in the visual pathway has been recently elucidated; however new studies on their distribution in the brain and spinal cord have revealed that they are more spread than originally thought, and thus it will be important to determine their physiological contribution to the GABAergic transmission in other areas of the central nervous system. In addition, molecular modeling has revealed peculiar traits of these receptors that have impacted on the interpretations of the latest pharmacolgical and biophysical findings. Finally, sequencing of several vertebrate genomes has permitted a comparative analysis of the organization of the GABAρ genes.
Collapse
Affiliation(s)
- Gustavo Martínez-Delgado
- Instituto de Neurbiología, Departamento de Neurobiología Celular y Molecular, Laboratorio D15, Campus UNAM Juriquilla. Querétaro 76230, México
| | | | | | | |
Collapse
|
21
|
Rosas-Arellano A, Parodi J, Machuca-Parra AI, Sánchez-Gutiérrez A, Inestrosa NC, Miledi R, Martínez-Torres A. The GABA(A)ρ receptors in hippocampal spontaneous activity and their distribution in hippocampus, amygdala and visual cortex. Neurosci Lett 2011; 500:20-5. [PMID: 21683123 DOI: 10.1016/j.neulet.2011.05.235] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Revised: 05/13/2011] [Accepted: 05/31/2011] [Indexed: 10/18/2022]
Abstract
A bicuculline-resistant and TPMPA-sensitive GABAergic component was identified in hippocampal neurons in culture and in acute isolated brain slices. In both preparations, total GABAergic activity showed two inactivation kinetics: fast and slow. RT-PCR, in situ hybridization (ISH) and immunohistochemistry detected expression of GABAρ subunits. Immunogold and electron microscopy indicated that the receptors are mostly extrasynaptic. In addition, by RT-PCR and immunofluorescence we found GABAρ present in amygdala and visual cortex.
Collapse
Affiliation(s)
- Abraham Rosas-Arellano
- Departamento de Neurobiología Celular y Molecular, Laboratorio de Neurobiología Molecular y Celular, Instituto de Neurobiología, Campus UNAM-Juriquilla, Querétaro, QRO 76230, Mexico
| | | | | | | | | | | | | |
Collapse
|
22
|
Lehner M, Wisłowska-Stanek A, Skórzewska A, Maciejak P, Szyndler J, Turzyńska D, Sobolewska A, Płaźnik A. Differences in the density of GABA-A receptor alpha-2 subunits and gephyrin in brain structures of rats selected for low and high anxiety in basal and fear-stimulated conditions, in a model of contextual fear conditioning. Neurobiol Learn Mem 2010; 94:499-508. [DOI: 10.1016/j.nlm.2010.09.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2010] [Revised: 08/31/2010] [Accepted: 09/01/2010] [Indexed: 11/27/2022]
|
23
|
Viviani D, Terrettaz T, Magara F, Stoop R. Oxytocin enhances the inhibitory effects of diazepam in the rat central medial amygdala. Neuropharmacology 2009; 58:62-8. [PMID: 19589347 DOI: 10.1016/j.neuropharm.2009.06.039] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2009] [Revised: 06/17/2009] [Accepted: 06/29/2009] [Indexed: 10/20/2022]
Abstract
Oxytocin is a neuropeptide that can reduce neophobia and improve social affiliation. In vitro, oxytocin induces a massive release of GABA from neurons in the lateral division of the central amygdala which results in inhibition of a subpopulation of peripherally projecting neurons in the medial division of the central amygdala (CeM). Common anxiolytics, such as diazepam, act as allosteric modulators of GABA(A) receptors. Because oxytocin and diazepam act on GABAergic transmission, it is possible that oxytocin can potentiate the inhibitory effects of diazepam if both exert their pre, - respectively postsynaptic effects on the same inhibitory circuit in the central amygdala. We found that in CeM neurons in which diazepam increased the inhibitory postsynaptic current (IPSC) decay time, TGOT (a specific oxytocin receptor agonist) increased IPSC frequency. Combined application of diazepam and TGOT resulted in generation of IPSCs with increased frequency, decay times as well as amplitudes. While individual saturating concentrations of TGOT and diazepam each decreased spontaneous spiking frequency of CeM neurons to similar extent, co-application of the two was still able to cause a significantly larger decrease. These findings show that oxytocin and diazepam act on different components of the same GABAergic circuit in the central amygdala and that oxytocin can facilitate diazepam effects when used in combination. This raises the possibility that neuropeptides could be clinically used in combination with currently used anxiolytic treatments to improve their therapeutic efficacy.
Collapse
Affiliation(s)
- D Viviani
- Centre for Psychiatric Neurosciences, Department of Psychiatry, University Hospital Center Lausanne (CHUV), Prilly-Lausanne, Switzerland
| | | | | | | |
Collapse
|
24
|
Esmaeili A, Lynch JW, Sah P. GABAA receptors containing gamma1 subunits contribute to inhibitory transmission in the central amygdala. J Neurophysiol 2008; 101:341-9. [PMID: 19004994 DOI: 10.1152/jn.90991.2008] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
gamma-Aminobutyric acid (GABA) is the primary inhibitory transmitter in the mammalian brain. This inhibition is mediated by type A (GABA(A)) receptors that are pentameric proteins assembled from 14 different subunits. Although inhibitory synaptic transmission has been studied in the amygdala, the subunit composition of receptors present at different synapses is not well understood. In this study we examined the subunit composition of GABA(A) receptors at synapses in the basolateral and central amygdala. Using receptors expressed in HEK293 cells we first determined the pharmacology of receptors of different subunit compositions. We then used this pharmacological profile to test the properties of receptors present at synapses in the central and basolateral amygdala. These results show that the GABA(A) receptor subunits are differentially distributed in the amygdala. Our data indicate that in the basolateral amygdala, GABAergic synapses are likely composed of receptors that contain alpha2betaxgamma2 subunits. In the central amygdala receptors at the medial input, carrying afferents from the bed nucleus of the stria terminalis contain similar receptors, whereas in the lateral input GABA receptors likely contain gamma1 subunits. These inputs arise from the intercalated cells masses, thought to be responsible for mediating extinction of conditioned fear, raising the possibility of new targets for the treatment of anxiety-related disorders.
Collapse
Affiliation(s)
- Abolghasem Esmaeili
- The Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | | | | |
Collapse
|
25
|
Prenatal dexamethasone exposure affects anxiety-like behaviour and neuroendocrine systems in an age-dependent manner. Neurosci Res 2008; 60:364-71. [DOI: 10.1016/j.neures.2007.12.005] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2007] [Revised: 12/07/2007] [Accepted: 12/13/2007] [Indexed: 11/17/2022]
|
26
|
Savić MM, Clayton T, Furtmüller R, Gavrilović I, Samardzić J, Savić S, Huck S, Sieghart W, Cook JM. PWZ-029, a compound with moderate inverse agonist functional selectivity at GABA(A) receptors containing alpha5 subunits, improves passive, but not active, avoidance learning in rats. Brain Res 2008; 1208:150-9. [PMID: 18394590 DOI: 10.1016/j.brainres.2008.02.020] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2007] [Revised: 01/26/2008] [Accepted: 02/04/2008] [Indexed: 10/22/2022]
Abstract
Benzodiazepine (BZ) site ligands affect vigilance, anxiety, memory processes, muscle tone and epileptogenic propensity through modulation of neurotransmission at GABA(A) receptors containing alpha1, alpha2, alpha3 or alpha5 subunits, and may have numerous experimental and clinical applications. The ability of non-selective BZ site inverse agonists to enhance cognition, documented in animal models and human studies, is clinically not feasible due to potentially unacceptable psychomotor effects. Most investigations to date have proposed the alpha1 and/or alpha5 subunit-containing GABA(A) receptors as comprising the memory-modulating population of these receptors. The novel ligand PWZ-029, which we synthesized and characterized electrophysiologically, possesses in vitro binding selectivity and moderate inverse agonist functional selectivity at alpha5-containing GABA(A) receptors. This ligand has also been examined in rats in the passive and active avoidance, spontaneous locomotor activity, elevated plus maze and grip strength tests, primarily predictive of the effects on the memory acquisition, basal locomotor activity, anxiety level and muscle tone, respectively. The improvement of task learning was detected at the dose of 5 mg/kg in the passive, but not active avoidance test. The inverse agonist PWZ-029 had no effect on anxiety or muscle tone, whereas at higher doses (10 and 20 mg/kg) it decreased locomotor activity. This effect was antagonized by flumazenil and also by the lower (but not the higher) dose of an agonist (SH-053-R-CH3-2'F) selective for GABA(A) receptors containing the alpha5 subunit. The hypolocomotor effect of PWZ-029 was not antagonized by the antagonist ss-CCt exhibiting a preferential affinity for alpha1-subunit-containing receptors. These data suggest that moderate negative modulation at GABA(A) receptors containing the alpha5 subunit is a sufficient condition for eliciting enhanced encoding/consolidation of declarative memory, while the influence of higher doses of modulators at these receptors on motor activity shows an intricate pattern whose relevance and mechanism await to be defined.
Collapse
Affiliation(s)
- Miroslav M Savić
- Department of Pharmacology, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11221 Belgrade, Serbia.
| | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Heldt SA, Ressler KJ. Forebrain and midbrain distribution of major benzodiazepine-sensitive GABAA receptor subunits in the adult C57 mouse as assessed with in situ hybridization. Neuroscience 2007; 150:370-85. [PMID: 17950542 DOI: 10.1016/j.neuroscience.2007.09.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2007] [Revised: 08/27/2007] [Accepted: 10/03/2007] [Indexed: 10/22/2022]
Abstract
In the adult brain, GABA is the major inhibitory neurotransmitter. Understanding of the behavioral and pharmacological functions of GABA has been advanced by recent studies of mouse lines that possess mutations in various GABA receptor subtypes and associated proteins. Genetically altered mice have become important tools for discerning GABAergic function. Thus detailed knowledge of the anatomical distribution of different GABA(A) subtype receptors in mice is a prerequisite for understanding the neural circuitry underlying changes in normal and drug-induced behaviors seen in mutated mice. In the current study, we used in situ hybridization histochemistry with [(35)S]UTP-labeled riboprobes to examine the regional expression pattern of mRNA transcripts for seven major GABA(A) receptor subunits in adjacent coronal brain sections (alpha 1, alpha 2, alpha 3, alpha 5, beta 2, beta 3, and gamma 2). Our results indicate that many of these GABAergic genes are co-expressed in much of the adult brain including the neocortex, hippocampus, amygdala, thalamus and striatum. However, each gene also shows a unique region-specific distribution pattern, indicative of distinct neuronal circuits that may serve specific physiological and pharmacological functions.
Collapse
Affiliation(s)
- S A Heldt
- Center for Behavioral Neuroscience, Department of Psychiatry and Behavioral Sciences, Yerkes National Primate Research Center, Emory University, 954 Gatewood Drive, Atlanta, GA 30329, USA.
| | | |
Collapse
|
28
|
Mathiasen LS, Rodgers RJ, Mirza NR. Comparative effects of nonselective and subtype-selective gamma-aminobutyric acidA receptor positive modulators in the rat-conditioned emotional response test. Behav Pharmacol 2007; 18:191-203. [PMID: 17426483 DOI: 10.1097/fbp.0b013e32814fcdd4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Benzodiazepine receptor anxiolytics show no selectivity between gamma-aminobutyric acid-A receptors containing alpha1, alpha2, alpha3 or alpha5 subunits. Pharmacological studies and data emerging from transgenic mouse models, however, predict that compounds with selective affinity and/or efficacy for gamma-aminobutyric acid-A receptor subtypes would have novel pharmacological profiles. Thus, the gamma-aminobutyric acid-A-alpha1 'affinity selective' drug zolpidem has a sedative-hypnotic profile, whereas L838,417, which has 'selective efficacy' for gamma-aminobutyric acid-A-alpha2, alpha3 and alpha5 receptors, has an anxiolytic-like profile. Here, we compare the nonselective benzodiazepine-site-positive modulators diazepam, lorazepam, midazolam, alprazolam and zopiclone with (i) gamma-aminobutyric acid-AA-alpha1 affinity selective compounds zolpidem and CL218,872 and (ii) L838,417, in the rat-conditioned emotional response test after systemic administration. Given the role of the basolateral amygdala in anxiety and the expression of alpha1, alpha2 and alpha3 subunits in this region, we also assessed the effects of bilateral infusion of L838,417 and midazolam directly into basolateral amygdala in the conditioned emotional response test. Nonselective modulators at low-moderate doses produced anxiolytic effects and sedation at higher doses. Zolpidem was inactive as an anxiolytic and engendered severe sedation, whereas CL218,872 produced an anxiolytic-like profile with minimal sedation. L838,417 produced an anxiolytic-like profile with no sedation, albeit producing behavioural disturbance at high doses. Infusion of midazolam and L838,417 into basolateral amygdala engendered anxiolytic-like effects, although both compounds were more effective after systemic injections, implicating additional brain sites in their anxiolytic-like actions after systemic administration. In conclusion, the diversity of effects of the compounds studied implicates both intrinsic efficacy and/or subtype selectivity as important determinants of anxiolytic-like effects in the rat-conditioned emotional response test.
Collapse
Affiliation(s)
- Linda S Mathiasen
- Division of In-vivo Pharmacology, NeuroSearch A/S, Ballerup, Denmark
| | | | | |
Collapse
|
29
|
Sinfield JL, Collins DR. Induction of synchronous oscillatory activity in the rat lateral amygdala in vitro is dependent on gap junction activity. Eur J Neurosci 2007; 24:3091-5. [PMID: 17156370 DOI: 10.1111/j.1460-9568.2006.05202.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Synchronized and rhythmic activity within the amygdala is thought to play a pivotal role in the generation of fear- and anxiety-related behaviour. The aim here was to determine the validity of the in vitro amygdala slice preparation to investigate the generation of rhythmic activity similar to that observed in vivo. Extracellular population activity recorded from the lateral nucleus of the amygdala in vitro showed significant enhancement of activity within the theta-band frequency (3-9 Hz) in the presence of kainic acid (100 nm; n=18). Alterations in the patterns of oscillatory activity within the gamma frequency band (20-40 Hz) were observed in the presence of (RS)-3,5-dihydroxyphenylglycine (10 microm; n=7) or carbachol (50 microm; n=5). Theta frequency oscillatory activity was blocked in the presence of the gap junction blocker carbenoxolone (100 mm), whereas gamma frequency oscillatory activity showed increased variability in the dominant frequency of rhythmic activity. The results suggest that the neuronal circuitry of the amygdala in vitro is capable of generating and sustaining rhythmic activity and that intercellular communication via gap junctions may play a role in the synchronization of population activity underlying this oscillatory activity.
Collapse
Affiliation(s)
- James L Sinfield
- MOAC Doctoral Training Centre, University of Warwick, Coventry, CV4 7AL, UK
| | | |
Collapse
|
30
|
Nomura H, Sakai A, Nagano M, Umino M, Suzuki H. Expression changes of cation chloride cotransporters in the rat spinal cord following intraplantar formalin. Neurosci Res 2006; 56:435-40. [PMID: 17007947 DOI: 10.1016/j.neures.2006.08.012] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2006] [Revised: 08/18/2006] [Accepted: 08/25/2006] [Indexed: 11/25/2022]
Abstract
Cation chloride cotransporters, K(+)-Cl(-) cotransporter 2 (KCC2) and Na(+)-K(+)-Cl(-) cotransporter 1 (NKCC1) are reported to be expressed in the neurons in the spinal cord and regulate intracellular Cl(-) concentration. Evidence has been accumulating that the expression of cation chloride cotransporters changes in inflammatory or neuropathic pain, and such changes take a part in pathophysiology of the persistent pain states. However, it is largely unknown how these cotransporters contribute to hyperalgesia in the acute pain state. We, therefore, investigated expression changes of KCC2 and NKCC1 in the spinal dorsal horn of the rat after the intraplantar injection of formalin as an acute nociceptive stimulus. The rats showed two phases (phases 1 and 2) of increase in pain-related behavior in response to formalin. We found that expression of KCC2-like immunoreactivity (IR) was reduced in lamina I and II in the lumbar spinal cord on the stimulated side in phase 1, and then recovered gradually. In contrast, the number of NKCC1-like IR-positive cells was unchanged over the period examined. These results suggest that KCC2, rather than NKCC1, mainly contributes to modulating excitability of the dorsal spinal cord neurons in the initial stage of formalin-evoked hyperalgesia.
Collapse
Affiliation(s)
- Hidehiko Nomura
- Anesthesiology and Clinical Physiology, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Tokyo, Japan
| | | | | | | | | |
Collapse
|