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Kim SH, An K, Namkung H, Saito A, Rannals MD, Moore JR, Mihaljevic M, Saha S, Oh S, Kondo MA, Ishizuka K, Yang K, Maher BJ, Niwa M, Sawa A. Anterior Insula-Associated Social Novelty Recognition: Pivotal Roles of a Local Retinoic Acid Cascade and Oxytocin Signaling. Am J Psychiatry 2022; 180:305-317. [PMID: 36128683 DOI: 10.1176/appi.ajp.21010053] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Deficits in social cognition consistently underlie functional disabilities in a wide range of psychiatric disorders. Neuroimaging studies have suggested that the anterior insula is a "common core" brain region that is impaired across neurological and psychiatric disorders, which include social cognition deficits. Nevertheless, neurobiological mechanisms of the anterior insula for social cognition remain elusive. This study aims to fill this knowledge gap. METHODS To determine the role of the anterior insula in social cognition, the authors manipulated expression of Cyp26B1, an anterior insula-enriched molecule that is crucial for retinoic acid degradation and is involved in the pathology of neuropsychiatric conditions. Social cognition was mainly assayed using the three-chamber social interaction test. Multimodal analyses were conducted at the molecular, cellular, circuitry, and behavioral levels. RESULTS At the molecular and cellular level, anterior insula-mediated social novelty recognition is maintained by proper activity of the layer 5 pyramidal neurons, for which retinoic acid-mediated gene transcription can play a role. The authors also demonstrate that oxytocin influences the anterior insula-mediated social novelty recognition, although not by direct projection of oxytocin neurons, nor by direct diffusion of oxytocin to the anterior insula, which contrasts with the modes of oxytocin regulation onto the posterior insula. Instead, oxytocin affects oxytocin receptor-expressing neurons in the dorsal raphe nucleus, where serotonergic neurons are projected to the anterior insula. Furthermore, the authors show that serotonin 5-HT2C receptor expressed in the anterior insula influences social novelty recognition. CONCLUSIONS The anterior insula plays a pivotal role in social novelty recognition that is partly regulated by a local retinoic acid cascade but also remotely regulated by oxytocin via a long-range circuit mechanism.
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Affiliation(s)
- Sun-Hong Kim
- Departments of Psychiatry (Kim, An, Namkung, Saito, Moore, Mihaljevic, Saha, Oh, Kondo, Ishizuka, Yang, Maher, Niwa, Sawa), Neuroscience (Maher, Sawa), Biomedical Engineering (Namkung, Sawa), Pharmacology (Sawa), and Genetic Medicine (Sawa), Johns Hopkins University School of Medicine, Baltimore; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore (Sawa); Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore (Rannals, Oh, Maher); Neuroscience Research Australia, Sydney (Kondo); Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham School of Medicine, Birmingham (Niwa)
| | - Kyongman An
- Departments of Psychiatry (Kim, An, Namkung, Saito, Moore, Mihaljevic, Saha, Oh, Kondo, Ishizuka, Yang, Maher, Niwa, Sawa), Neuroscience (Maher, Sawa), Biomedical Engineering (Namkung, Sawa), Pharmacology (Sawa), and Genetic Medicine (Sawa), Johns Hopkins University School of Medicine, Baltimore; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore (Sawa); Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore (Rannals, Oh, Maher); Neuroscience Research Australia, Sydney (Kondo); Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham School of Medicine, Birmingham (Niwa)
| | - Ho Namkung
- Departments of Psychiatry (Kim, An, Namkung, Saito, Moore, Mihaljevic, Saha, Oh, Kondo, Ishizuka, Yang, Maher, Niwa, Sawa), Neuroscience (Maher, Sawa), Biomedical Engineering (Namkung, Sawa), Pharmacology (Sawa), and Genetic Medicine (Sawa), Johns Hopkins University School of Medicine, Baltimore; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore (Sawa); Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore (Rannals, Oh, Maher); Neuroscience Research Australia, Sydney (Kondo); Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham School of Medicine, Birmingham (Niwa)
| | - Atsushi Saito
- Departments of Psychiatry (Kim, An, Namkung, Saito, Moore, Mihaljevic, Saha, Oh, Kondo, Ishizuka, Yang, Maher, Niwa, Sawa), Neuroscience (Maher, Sawa), Biomedical Engineering (Namkung, Sawa), Pharmacology (Sawa), and Genetic Medicine (Sawa), Johns Hopkins University School of Medicine, Baltimore; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore (Sawa); Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore (Rannals, Oh, Maher); Neuroscience Research Australia, Sydney (Kondo); Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham School of Medicine, Birmingham (Niwa)
| | - Matthew D Rannals
- Departments of Psychiatry (Kim, An, Namkung, Saito, Moore, Mihaljevic, Saha, Oh, Kondo, Ishizuka, Yang, Maher, Niwa, Sawa), Neuroscience (Maher, Sawa), Biomedical Engineering (Namkung, Sawa), Pharmacology (Sawa), and Genetic Medicine (Sawa), Johns Hopkins University School of Medicine, Baltimore; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore (Sawa); Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore (Rannals, Oh, Maher); Neuroscience Research Australia, Sydney (Kondo); Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham School of Medicine, Birmingham (Niwa)
| | - James R Moore
- Departments of Psychiatry (Kim, An, Namkung, Saito, Moore, Mihaljevic, Saha, Oh, Kondo, Ishizuka, Yang, Maher, Niwa, Sawa), Neuroscience (Maher, Sawa), Biomedical Engineering (Namkung, Sawa), Pharmacology (Sawa), and Genetic Medicine (Sawa), Johns Hopkins University School of Medicine, Baltimore; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore (Sawa); Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore (Rannals, Oh, Maher); Neuroscience Research Australia, Sydney (Kondo); Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham School of Medicine, Birmingham (Niwa)
| | - Marina Mihaljevic
- Departments of Psychiatry (Kim, An, Namkung, Saito, Moore, Mihaljevic, Saha, Oh, Kondo, Ishizuka, Yang, Maher, Niwa, Sawa), Neuroscience (Maher, Sawa), Biomedical Engineering (Namkung, Sawa), Pharmacology (Sawa), and Genetic Medicine (Sawa), Johns Hopkins University School of Medicine, Baltimore; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore (Sawa); Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore (Rannals, Oh, Maher); Neuroscience Research Australia, Sydney (Kondo); Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham School of Medicine, Birmingham (Niwa)
| | - Sneha Saha
- Departments of Psychiatry (Kim, An, Namkung, Saito, Moore, Mihaljevic, Saha, Oh, Kondo, Ishizuka, Yang, Maher, Niwa, Sawa), Neuroscience (Maher, Sawa), Biomedical Engineering (Namkung, Sawa), Pharmacology (Sawa), and Genetic Medicine (Sawa), Johns Hopkins University School of Medicine, Baltimore; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore (Sawa); Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore (Rannals, Oh, Maher); Neuroscience Research Australia, Sydney (Kondo); Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham School of Medicine, Birmingham (Niwa)
| | - Seyun Oh
- Departments of Psychiatry (Kim, An, Namkung, Saito, Moore, Mihaljevic, Saha, Oh, Kondo, Ishizuka, Yang, Maher, Niwa, Sawa), Neuroscience (Maher, Sawa), Biomedical Engineering (Namkung, Sawa), Pharmacology (Sawa), and Genetic Medicine (Sawa), Johns Hopkins University School of Medicine, Baltimore; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore (Sawa); Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore (Rannals, Oh, Maher); Neuroscience Research Australia, Sydney (Kondo); Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham School of Medicine, Birmingham (Niwa)
| | - Mari A Kondo
- Departments of Psychiatry (Kim, An, Namkung, Saito, Moore, Mihaljevic, Saha, Oh, Kondo, Ishizuka, Yang, Maher, Niwa, Sawa), Neuroscience (Maher, Sawa), Biomedical Engineering (Namkung, Sawa), Pharmacology (Sawa), and Genetic Medicine (Sawa), Johns Hopkins University School of Medicine, Baltimore; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore (Sawa); Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore (Rannals, Oh, Maher); Neuroscience Research Australia, Sydney (Kondo); Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham School of Medicine, Birmingham (Niwa)
| | - Koko Ishizuka
- Departments of Psychiatry (Kim, An, Namkung, Saito, Moore, Mihaljevic, Saha, Oh, Kondo, Ishizuka, Yang, Maher, Niwa, Sawa), Neuroscience (Maher, Sawa), Biomedical Engineering (Namkung, Sawa), Pharmacology (Sawa), and Genetic Medicine (Sawa), Johns Hopkins University School of Medicine, Baltimore; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore (Sawa); Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore (Rannals, Oh, Maher); Neuroscience Research Australia, Sydney (Kondo); Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham School of Medicine, Birmingham (Niwa)
| | - Kun Yang
- Departments of Psychiatry (Kim, An, Namkung, Saito, Moore, Mihaljevic, Saha, Oh, Kondo, Ishizuka, Yang, Maher, Niwa, Sawa), Neuroscience (Maher, Sawa), Biomedical Engineering (Namkung, Sawa), Pharmacology (Sawa), and Genetic Medicine (Sawa), Johns Hopkins University School of Medicine, Baltimore; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore (Sawa); Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore (Rannals, Oh, Maher); Neuroscience Research Australia, Sydney (Kondo); Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham School of Medicine, Birmingham (Niwa)
| | - Brady J Maher
- Departments of Psychiatry (Kim, An, Namkung, Saito, Moore, Mihaljevic, Saha, Oh, Kondo, Ishizuka, Yang, Maher, Niwa, Sawa), Neuroscience (Maher, Sawa), Biomedical Engineering (Namkung, Sawa), Pharmacology (Sawa), and Genetic Medicine (Sawa), Johns Hopkins University School of Medicine, Baltimore; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore (Sawa); Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore (Rannals, Oh, Maher); Neuroscience Research Australia, Sydney (Kondo); Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham School of Medicine, Birmingham (Niwa)
| | - Minae Niwa
- Departments of Psychiatry (Kim, An, Namkung, Saito, Moore, Mihaljevic, Saha, Oh, Kondo, Ishizuka, Yang, Maher, Niwa, Sawa), Neuroscience (Maher, Sawa), Biomedical Engineering (Namkung, Sawa), Pharmacology (Sawa), and Genetic Medicine (Sawa), Johns Hopkins University School of Medicine, Baltimore; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore (Sawa); Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore (Rannals, Oh, Maher); Neuroscience Research Australia, Sydney (Kondo); Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham School of Medicine, Birmingham (Niwa)
| | - Akira Sawa
- Departments of Psychiatry (Kim, An, Namkung, Saito, Moore, Mihaljevic, Saha, Oh, Kondo, Ishizuka, Yang, Maher, Niwa, Sawa), Neuroscience (Maher, Sawa), Biomedical Engineering (Namkung, Sawa), Pharmacology (Sawa), and Genetic Medicine (Sawa), Johns Hopkins University School of Medicine, Baltimore; Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore (Sawa); Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore (Rannals, Oh, Maher); Neuroscience Research Australia, Sydney (Kondo); Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham School of Medicine, Birmingham (Niwa)
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Hesselgrave N, Troppoli TA, Wulff AB, Cole AB, Thompson SM. Harnessing psilocybin: antidepressant-like behavioral and synaptic actions of psilocybin are independent of 5-HT2R activation in mice. Proc Natl Acad Sci U S A 2021; 118:e2022489118. [PMID: 33850049 PMCID: PMC8092378 DOI: 10.1073/pnas.2022489118] [Citation(s) in RCA: 175] [Impact Index Per Article: 58.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Depression is a widespread and devastating mental illness and the search for rapid-acting antidepressants remains critical. There is now exciting evidence that the psychedelic compound psilocybin produces not only powerful alterations of consciousness, but also rapid and persistent antidepressant effects. How psilocybin exerts its therapeutic actions is not known, but it is widely presumed that these actions require altered consciousness, which is known to be dependent on serotonin 2A receptor (5-HT2AR) activation. This hypothesis has never been tested, however. We therefore asked whether psilocybin would exert antidepressant-like responses in mice and, if so, whether these responses required 5-HT2AR activation. Using chronically stressed male mice, we observed that a single injection of psilocybin reversed anhedonic responses assessed with the sucrose preference and female urine preference tests. The antianhedonic response to psilocybin was accompanied by a strengthening of excitatory synapses in the hippocampus-a characteristic of traditional and fast-acting antidepressants. Neither behavioral nor electrophysiological responses to psilocybin were prevented by pretreatment with the 5-HT2A/2C antagonist ketanserin, despite positive evidence of ketanserin's efficacy. We conclude that psilocybin's mechanism of antidepressant action can be studied in animal models and suggest that altered perception may not be required for its antidepressant effects. We further suggest that a 5-HT2AR-independent restoration of synaptic strength in cortico-mesolimbic reward circuits may contribute to its antidepressant action. The possibility of combining psychedelic compounds and a 5-HT2AR antagonist offers a potential means to increase their acceptance and clinical utility and should be studied in human depression.
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Affiliation(s)
- Natalie Hesselgrave
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD 21201
- Medical Scientist Training Program, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Timothy A Troppoli
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201
- Molecular Medicine Program, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Andreas B Wulff
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Anthony B Cole
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD 21201
- Medical Scientist Training Program, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Scott M Thompson
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201;
- Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD 21201
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3
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Bombardi C, Grandis A, Pivac N, Sagud M, Lucas G, Chagraoui A, Lemaire-Mayo V, De Deurwaerdère P, Di Giovanni G. Serotonin modulation of hippocampal functions: From anatomy to neurotherapeutics. PROGRESS IN BRAIN RESEARCH 2021; 261:83-158. [PMID: 33785139 DOI: 10.1016/bs.pbr.2021.01.031] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The hippocampal region receives a dense serotoninergic innervation originating from both medial and dorsal raphe nuclei. This innervation regulates hippocampal activity through the activation of distinct receptor families that are expressed in excitatory and inhibitory neurons, terminals of several afferent neurotransmitter systems, and glial cells. Preclinical and clinical studies indicate that hippocampal dysfunctions are involved in learning and memory deficits, dementia, Alzheimer's disease, epilepsy and mood disorders such as anxiety, depression and post-traumatic syndrome disorder, whereas the hippocampus participates also in the therapeutic mechanisms of numerous medicines. Not surprisingly, several drugs acting via 5-HT mechanisms are efficacious to some extent in some diseases and the link between 5-HT and the hippocampus although clear remains difficult to untangle. For this reason, we review reported data concerning the distribution and the functional roles of the 5-HT receptors in the hippocampal region in health and disease. The impact of the 5-HT systems on the hippocampal function is such that the research of new 5-HT mechanisms and drugs is still very active. It concerns notably drugs acting at the 5-HT1A,2A,2C,4,6 receptor subtypes, in addition to the already existing drugs including the selective serotonin reuptake inhibitors.
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Affiliation(s)
- Cristiano Bombardi
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy.
| | - Annamaria Grandis
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Nela Pivac
- Division of Molecular Medicine, Rudier Boskovic Institute, Zagreb, Croatia
| | - Marina Sagud
- Clinical Hospital Center Zagreb and School of Medicine University of Zagreb, Zagreb, Croatia
| | - Guillaume Lucas
- Neurocentre Magendie, INSERM 1215, Université de Bordeaux, Bordeaux, France
| | - Abdeslam Chagraoui
- Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, Institute for Research and Innovation in Biomedicine of Normandy (IRIB), Normandie University, UNIROUEN, INSERM U1239, Rouen, France; Department of Medical Biochemistry, Rouen University Hospital, Rouen, France
| | - Valérie Lemaire-Mayo
- Centre National de la Recherche Scientifique, Institut des Neurosciences Intégratives et Cognitives d'Aquitaine, UMR 5287, Bordeaux, France
| | - Philippe De Deurwaerdère
- Centre National de la Recherche Scientifique, Institut des Neurosciences Intégratives et Cognitives d'Aquitaine, UMR 5287, Bordeaux, France
| | - Giuseppe Di Giovanni
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta; Neuroscience Division, School of Biosciences, Cardiff University, Cardiff, United Kingdom
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4
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Deidda G, Crunelli V, Di Giovanni G. 5-HT/GABA interaction in epilepsy. PROGRESS IN BRAIN RESEARCH 2021; 259:265-286. [PMID: 33541679 DOI: 10.1016/bs.pbr.2021.01.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Epilepsy is a neurological condition characterized by synchronous neuronal oscillations (seizures) in the electroencephalogram. Seizures are classified in focal or generalized (depending on the brain territory interested during seizures), and in convulsive and/or not convulsive (depending on the presence or not of involuntary movements). The current pharmacological treatments are mainly based on GABA modulation although different neurotransmitters are also involved in epilepsy, including serotonin. However despite much extensive progress in the understanding of epilepsy mechanisms, still, a percentage of people with epilepsy are pharmaco-resistant calling for the need for new therapeutic targets. Here we review preclinical and human evidence showing that serotonin modulates epilepsy that this likely happens via a major modulation/interaction with GABA.
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Affiliation(s)
- Gabriele Deidda
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta.
| | - Vincenzo Crunelli
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta; Neuroscience Division, School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | - Giuseppe Di Giovanni
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta; Neuroscience Division, School of Biosciences, Cardiff University, Cardiff, United Kingdom
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Agahari FA, Stricker C. Serotonergic Modulation of Spontaneous and Evoked Transmitter Release in Layer II Pyramidal Cells of Rat Somatosensory Cortex. Cereb Cortex 2021; 31:1182-1200. [PMID: 33063109 DOI: 10.1093/cercor/bhaa285] [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: 11/12/2022] Open
Abstract
As axons from the raphe nuclei densely innervate the somatosensory cortex, we investigated how serotonin (5-HT) modulates transmitter release in layer II pyramidal cells of rat barrel cortex. In the presence of tetrodotoxin and gabazine, 10 μM 5-HT caused a waxing and waning in the frequency of miniature excitatory postsynaptic currents (mEPSC) with no effect on amplitude. Specifically, within 15 min of recording the mEPSC frequency initially increased by 28 ± 7%, then dropped to below control (-15 ± 3%), before resurging back to 27 ± 7% larger than control. These changes were seen in 47% of pyramidal cells (responders) and were mediated by 5-HT2C receptors (5-HT2CR). Waxing resulted from phospholipase C activation, IP3 production, and Ca2+ release from presynaptic stores. Waning was prevented if PKC was blocked. In contrast, in paired recordings, the unitary EPSC amplitude was reduced by 50 ± 3% after 5-HT exposure in almost all cases with no significant effect on paired-pulse ratio and synaptic dynamics. This sustained EPSC reduction was also caused by 5-HT2R, but was mediated by presynaptic Gβγ subunits likely limiting influx through CaV2 channels. EPSC reduction, together with enhanced spontaneous noise in a restricted subset of inputs, could temporarily diminish the signal-to-noise ratio and affect the computation in the neocortical microcircuit.
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Affiliation(s)
- Fransiscus Adrian Agahari
- Neuronal Network Laboratory, Eccles Institute of Neuroscience, The John Curtin School of Medical Research, Australian National University, Acton ACT 2601, Australia.,Division of Cerebral Circuitry, National Institute for Physiological Sciences, Okazaki 444-8787, Japan.,Brain Science Institute, Tamagawa University, Tokyo 194-8610, Japan
| | - Christian Stricker
- Neuronal Network Laboratory, Eccles Institute of Neuroscience, The John Curtin School of Medical Research, Australian National University, Acton ACT 2601, Australia
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Gerbier R, Ndiaye-Lobry D, Martinez de Morentin PB, Cecon E, Heisler LK, Delagrange P, Gbahou F, Jockers R. Pharmacological evidence for transactivation within melatonin MT 2 and serotonin 5-HT 2C receptor heteromers in mouse brain. FASEB J 2020; 35:e21161. [PMID: 33156577 DOI: 10.1096/fj.202000305r] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 10/08/2020] [Accepted: 10/19/2020] [Indexed: 01/01/2023]
Abstract
Association of G protein-coupled receptors into heterodimeric complexes has been reported for over 50 receptor pairs in vitro but functional in vivo validation remains a challenge. Our recent in vitro studies defined the functional fingerprint of heteromers composed of Gi -coupled melatonin MT2 receptors and Gq -coupled serotonin 5-HT2C receptors, in which melatonin transactivates phospholipase C (PLC) through 5-HT2C . Here, we identified this functional fingerprint in the mouse brain. Gq protein activation was probed by [35 S]GTPγS incorporation followed by Gq immunoprecipitation, and PLC activation by determining the inositol phosphate levels in brain lysates of animals previously treated with melatonin. Melatonin concentration-dependently activated Gq proteins and PLC in the hypothalamus and cerebellum but not in cortex. These effects were inhibited by the 5-HT2C receptor-specific inverse agonist SB-243213, and were absent in MT2 and 5-HT2C knockout mice, fully recapitulating previous in vitro data and indicating the involvement of MT2 /5-HT2C heteromers. The antidepressant agomelatine had a similar effect than melatonin when applied alone but blocked the melatonin-promoted Gq activation due to its 5-HT2C antagonistic component. Collectively, we provide strong functional evidence for the existence of MT2 /5-HT2C heteromeric complexes in mouse brain. These heteromers might participate in the in vivo effects of agomelatine.
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Affiliation(s)
- Romain Gerbier
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
| | | | | | - Erika Cecon
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
| | | | | | - Florence Gbahou
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
| | - Ralf Jockers
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
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Shin D, Cho KH, Joo K, Rhie DJ. Layer-specific serotonergic induction of long-term depression in the prefrontal cortex of rats. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2020; 24:517-527. [PMID: 33093273 PMCID: PMC7585589 DOI: 10.4196/kjpp.2020.24.6.517] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 09/29/2020] [Accepted: 10/04/2020] [Indexed: 11/15/2022]
Abstract
Layer 2/3 pyramidal neurons (L2/3 PyNs) of the cortex extend their basal dendrites near the soma and as apical dendritic tufts in layer 1, which mainly receive feedforward and feedback inputs, respectively. It is suggested that neuromodulators such as serotonin and acetylcholine may regulate the information flow between brain structures depending on the brain state. However, little is known about the dendritic compartment-specific induction of synaptic transmission in single PyNs. Here, we studied layer-specific serotonergic and cholinergic induction of long-term synaptic plasticity in L2/3 PyNs of the agranular insular cortex, a lateral component of the orbitofrontal cortex. Using FM1-43 dye unloading, we verified that local electrical stimulation to layers 1 (L1) and 3 (L3) activated axon terminals mostly located in L1 and perisomatic area (L2/3). Independent and AMPA receptor-mediated excitatory postsynaptic potential was evoked by local electrical stimulation of either L1 or L3. Application of serotonin (5-HT, 10 μM) induced activity-dependent long-term depression (LTD) in L2/3 but not in L1 inputs. LTD induced by 5-HT was blocked by the 5-HT2 receptor antagonist ketanserin, an NMDA receptor antagonist and by intracellular Ca2+ chelation. The 5-HT2 receptor agonist α-me-5-HT mimicked the LTD induced by 5-HT. However, the application of carbachol induced muscarinic receptor-dependent LTD in both inputs. The differential layer-specific induction of LTD by neuromodulators might play an important role in information processing mechanism of the prefrontal cortex.
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Affiliation(s)
- Dongchul Shin
- Department of Physiology, The Catholic University of Korea, Seoul 06591, Korea
| | - Kwang-Hyun Cho
- Department of Physiology, The Catholic University of Korea, Seoul 06591, Korea
| | - Kayoung Joo
- Department of Physiology, The Catholic University of Korea, Seoul 06591, Korea
| | - Duck-Joo Rhie
- Department of Physiology, The Catholic University of Korea, Seoul 06591, Korea.,Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea
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Tanaka M, Watanabe Y. RNA Editing of Serotonin 2C Receptor and Alcohol Intake. Front Neurosci 2020; 13:1390. [PMID: 32009879 PMCID: PMC6971223 DOI: 10.3389/fnins.2019.01390] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 12/10/2019] [Indexed: 01/30/2023] Open
Abstract
Serotonin 2C receptor (5-HT2 CR) belongs to the superfamily of seven transmembrane domain receptors coupled to G proteins (GPCR). It is broadly distributed in the CNS and its expression is relatively high in the limbic system including the amygdala, nucleus accumbens (NAc), hippocampus, and hypothalamus. Based on its expression patterns and numerous pharmacological studies, 5-HT2 CR is thought to be involved in various brain functions including emotion, appetite, and motor behavior. Here, we review 5-HT2 CR and its relationship with alcohol intake with a particular focus on the involvement of 5-HT2 CR mRNA editing and its association with alcohol preference in mice. RNA editing is a post-transcriptional modification mechanism. In mammals, adenosine is converted to inosine by the deamination enzymes ADAR1 and ADAR2. 5-HT2 CR is the only GPCR subjected to RNA editing within the coding region. It has five editing sites in exon 5 that encode the second intracellular loop. Consequently, three amino acids residues (I156, N158, and I160) of the unedited receptor (INI) may be altered to differently edited isoforms, resulting in a change of receptor activity such as 5-HT potency and G-protein coupling. 5-HT2 CR in the NAc is involved in enhanced alcohol drinking after chronic alcohol exposure and alterations in 5-HT2 CR mRNA editing is important in determining the alcohol preference using different strains of mice and genetically modified mice. RNA editing of this receptor may participate in the development of alcoholism.
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Affiliation(s)
- Masaki Tanaka
- Department of Anatomy and Neurobiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Yoshihisa Watanabe
- Department of Basic Geriatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
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9
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Harvey BH, Regenass W, Dreyer W, Möller M. Social isolation rearing-induced anxiety and response to agomelatine in male and female rats: Role of corticosterone, oxytocin, and vasopressin. J Psychopharmacol 2019; 33:640-646. [PMID: 30789294 PMCID: PMC6537027 DOI: 10.1177/0269881119826783] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND The chronobiotic antidepressant, agomelatine, acts via re-entrainment of circadian rhythms. Earlier work has demonstrated late-life anxiety and reduced corticosterone in post-weaning social isolation reared (SIR) rats. Agomelatine was anxiolytic in this model but did not reverse hypocortisolemia. Reduced corticosterone or cortisol (in humans) is well-described in anxiety states, although the anxiolytic-like actions of agomelatine may involve targeting another mechanism. Central oxytocin and vasopressin exert anxiolytic and anxiogenic effects, respectively, and are subject to circadian fluctuation, while also showing sex-dependent differences in response to various challenges. AIMS AND METHODS If corticosterone is less involved in the anxiolytic-like actions of agomelatine in SIR rats, we wondered whether effects on vasopressin and oxytocin may mediate these actions, and whether sex-dependent effects are evident. Anxiety as assessed in the elevated plus maze, as well as plasma vasopressin, oxytocin, and corticosterone were analyzed in social vs SIR animals receiving sub-chronic treatment with vehicle or agomelatine (40 mg/kg/day intraperitoneally at 16:00) for 16 days. RESULTS Social isolation rearing induced significant anxiety together with increased plasma vasopressin levels, but decreased corticosterone and oxytocin. While corticosterone displayed sex-dependent changes, vasopressin, and oxytocin changes were independent of sex. Agomelatine suppressed anxiety as well as reversed elevated vasopressin in both male and female rats and partially reversed reduced oxytocin in female but not male rats. CONCLUSION SIR-associated anxiety later in life involves reduced corticosterone and oxytocin, and elevated vasopressin. The anxiolytic-like effects of agomelatine in SIR rats predominantly involve targeting of elevated vasopressin.
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Affiliation(s)
- Brian H Harvey
- Department of Pharmacology, North West University, Potchefstroom, South Africa,Center of Excellence for Pharmaceutical Sciences, North West University, Potchefstroom, South Africa,Brian H Harvey, Center of Excellence for Pharmaceutical Sciences, School of Pharmacy, North West University, Potchefstroom, South Africa.
| | - Wilmie Regenass
- Department of Pharmacology, North West University, Potchefstroom, South Africa,Center of Excellence for Pharmaceutical Sciences, North West University, Potchefstroom, South Africa
| | - Walter Dreyer
- Center of Excellence for Pharmaceutical Sciences, North West University, Potchefstroom, South Africa
| | - Marisa Möller
- Department of Pharmacology, North West University, Potchefstroom, South Africa,Center of Excellence for Pharmaceutical Sciences, North West University, Potchefstroom, South Africa
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10
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Wang X, Sun M, Gan L, Chen W. MK212, a 5-hydroxytryptamine 2C receptor agonist, inhibits conditioned avoidance responses independent of blocking endogenous dopamine release in rats. Prog Neuropsychopharmacol Biol Psychiatry 2019; 89:16-22. [PMID: 30145182 DOI: 10.1016/j.pnpbp.2018.08.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 07/31/2018] [Accepted: 08/23/2018] [Indexed: 10/28/2022]
Abstract
Although it is widely accepted that 5-hydroxytryptamine (5-HT) 2C receptor agonists produce antipsychotic effects by reducing endogenous dopamine release from presynaptic neurons, no direct evidence supports this. The aim of the present study was to investigate whether the antipsychotic effects induced by 5-HT2C receptor agonists are dependent on the inhibition of endogenous dopamine release. We developed a novel conditioned avoidance response paradigm to test this hypothesis. In this assay, rats in which dopamine was depleted by reserpine failed to show conditioned avoidance responses, and the acute administration of quinpirole reversed the disruption of avoidance responses induced by reserpine. This suggests that animals successfully showed conditioned avoidance responses independent of endogenous dopamine release under these experimental conditions. Our results revealed that MK212 (0.5 mg/kg) reduced avoidance responses triggered by quinpirole in dopamine-depleted rats. Therefore, 5-HT2C receptor agonists can inhibit conditioned avoidance responses independent of blocking endogenous dopamine release. Furthermore, the 5-HT2C receptor agonist, MK212, decreased the extracellular concentration of glutamate in the nucleus accumbens, indicating that this mechanism may be critical for the antipsychotic effects of 5-HT2C receptor agonists.
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Affiliation(s)
- Xiaqing Wang
- Key Laboratory of Cognition and Personality (Southwest University), Ministry of Education, Chongqing, China; Faculty of Psychology, Southwest University, Chongqing, China
| | - Meng Sun
- Key Laboratory of Cognition and Personality (Southwest University), Ministry of Education, Chongqing, China; Faculty of Psychology, Southwest University, Chongqing, China
| | - Lu Gan
- Key Laboratory of Cognition and Personality (Southwest University), Ministry of Education, Chongqing, China; Faculty of Psychology, Southwest University, Chongqing, China
| | - Weihai Chen
- Key Laboratory of Cognition and Personality (Southwest University), Ministry of Education, Chongqing, China; Faculty of Psychology, Southwest University, Chongqing, China.
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11
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Godar SC, Mosher LJ, Scheggi S, Devoto P, Moench KM, Strathman HJ, Jones CM, Frau R, Melis M, Gambarana C, Wilkinson B, DeMontis MG, Fowler SC, Coba MP, Wellman CL, Shih JC, Bortolato M. Gene-environment interactions in antisocial behavior are mediated by early-life 5-HT 2A receptor activation. Neuropharmacology 2019; 159:107513. [PMID: 30716416 DOI: 10.1016/j.neuropharm.2019.01.028] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 01/14/2019] [Accepted: 01/25/2019] [Indexed: 12/29/2022]
Abstract
The ontogeny of antisocial behavior (ASB) is rooted in complex gene-environment (G×E) interactions. The best-characterized of these interplays occurs between: a) low-activity alleles of the gene encoding monoamine oxidase A (MAOA), the main serotonin-degrading enzyme; and b) child maltreatment. The purpose of this study was to develop the first animal model of this G×E interaction, to help understand the neurobiological mechanisms of ASB and identify novel targets for its therapy. Maoa hypomorphic transgenic mice were exposed to an early-life stress regimen consisting of maternal separation and daily intraperitoneal saline injections and were then compared with their wild-type and non-stressed controls for ASB-related neurobehavioral phenotypes. Maoa hypomorphic mice subjected to stress from postnatal day (PND) 1 through 7 - but not during the second postnatal week - developed overt aggression, social deficits and abnormal stress responses from the fourth week onwards. On PND 8, these mice exhibited low resting heart rate - a well-established premorbid sign of ASB - and a significant and selective up-regulation of serotonin 5-HT2A receptors in the prefrontal cortex. Notably, both aggression and neonatal bradycardia were rescued by the 5-HT2 receptor antagonist ketanserin (1-3 mg kg-1, IP), as well as the selective 5-HT2A receptor blocker MDL-100,907 (volinanserin, 0.1-0.3 mg kg-1, IP) throughout the first postnatal week. These findings provide the first evidence of a molecular basis of G×E interactions in ASB and point to early-life 5-HT2A receptor activation as a key mechanism for the ontogeny of this condition. This article is part of the Special Issue entitled 'The neuropharmacology of social behavior: from bench to bedside'.
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Affiliation(s)
- Sean C Godar
- Dept. of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT, USA; Consortium for Translational Research on Aggression and Drug Abuse (ConTRADA), University of Kansas, Lawrence, KS, USA
| | - Laura J Mosher
- Dept. of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT, USA; Dept. of Pharmacology and Toxicology, University of Kansas, Lawrence, KS, USA
| | - Simona Scheggi
- Dept. of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT, USA; Dept. of Molecular and Developmental Medicine, University of Siena, Italy
| | - Paola Devoto
- Dept. of Biomedical Sciences, Section of Neuroscience, UNICA, Monserrato, Italy
| | - Kelly M Moench
- Dept. of Psychological and Brain Sciences, Program in Neural Science and Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, IN, USA
| | - Hunter J Strathman
- Dept. of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT, USA; Dept. of Pharmacology and Toxicology, University of Kansas, Lawrence, KS, USA
| | - Cori M Jones
- Dept. of Pharmacology and Toxicology, University of Kansas, Lawrence, KS, USA
| | - Roberto Frau
- Dept. of Biomedical Sciences, Section of Neuroscience, UNICA, Monserrato, Italy
| | - Miriam Melis
- Dept. of Biomedical Sciences, Section of Neuroscience, UNICA, Monserrato, Italy
| | - Carla Gambarana
- Dept. of Molecular and Developmental Medicine, University of Siena, Italy
| | - Brent Wilkinson
- Zilkha Neurogenetic Institute and Dept. of Psychiatry and Behavioral Sciences, University of Southern California, Los Angeles, CA, USA
| | | | - Stephen C Fowler
- Dept. of Pharmacology and Toxicology, University of Kansas, Lawrence, KS, USA
| | - Marcelo P Coba
- Zilkha Neurogenetic Institute and Dept. of Psychiatry and Behavioral Sciences, University of Southern California, Los Angeles, CA, USA
| | - Cara L Wellman
- Dept. of Psychological and Brain Sciences, Program in Neural Science and Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, IN, USA
| | - Jean C Shih
- Depts. of Pharmacology and Pharmaceutical Sciences and Integrated Anatomic Sciences, University of Southern California, Los Angeles, CA, USA
| | - Marco Bortolato
- Dept. of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT, USA; Consortium for Translational Research on Aggression and Drug Abuse (ConTRADA), University of Kansas, Lawrence, KS, USA.
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12
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Hackelberg S, Oliver D. Metabotropic Acetylcholine and Glutamate Receptors Mediate PI(4,5)P 2 Depletion and Oscillations in Hippocampal CA1 Pyramidal Neurons in situ. Sci Rep 2018; 8:12987. [PMID: 30154490 PMCID: PMC6113233 DOI: 10.1038/s41598-018-31322-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 08/17/2018] [Indexed: 01/24/2023] Open
Abstract
The sensitivity of many ion channels to phosphatidylinositol-4,5-bisphosphate (PIP2) levels in the cell membrane suggests that PIP2 fluctuations are important and general signals modulating neuronal excitability. Yet the PIP2 dynamics of central neurons in their native environment remained largely unexplored. Here, we examined the behavior of PIP2 concentrations in response to activation of Gq-coupled neurotransmitter receptors in rat CA1 hippocampal neurons in situ in acute brain slices. Confocal microscopy of the PIP2-selective molecular sensors tubbyCT-GFP and PLCδ1-PH-GFP showed that pharmacological activation of muscarinic acetylcholine (mAChR) or group I metabotropic glutamate (mGluRI) receptors induces transient depletion of PIP2 in the soma as well as in the dendritic tree. The observed PIP2 dynamics were receptor-specific, with mAChR activation inducing stronger PIP2 depletion than mGluRI, whereas agonists of other Gαq-coupled receptors expressed in CA1 neurons did not induce measureable PIP2 depletion. Furthermore, the data show for the first time neuronal receptor-induced oscillations of membrane PIP2 concentrations. Oscillatory behavior indicated that neurons can rapidly restore PIP2 levels during persistent activation of Gq and PLC. Electrophysiological responses to receptor activation resembled PIP2 dynamics in terms of time course and receptor specificity. Our findings support a physiological function of PIP2 in regulating electrical activity.
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Affiliation(s)
- Sandra Hackelberg
- Institute of Physiology and Pathophysiology, Philipps University, 35037, Marburg, Germany
- The Ken and Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Dominik Oliver
- Institute of Physiology and Pathophysiology, Philipps University, 35037, Marburg, Germany.
- DFG Research Training Group, Membrane Plasticity in Tissue Development and Remodeling, GRK 2213, Philipps University, Marburg, Germany.
- Center for Mind, Brain and Behavior (CMBB), Marburg and Giessen, Germany.
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13
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Sood A, Pati S, Bhattacharya A, Chaudhari K, Vaidya VA. Early emergence of altered 5‐HT
2A
receptor‐evoked behavior, neural activation and gene expression following maternal separation. Int J Dev Neurosci 2017; 65:21-28. [DOI: 10.1016/j.ijdevneu.2017.10.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 09/20/2017] [Accepted: 10/12/2017] [Indexed: 01/15/2023] Open
Affiliation(s)
- Ankit Sood
- Department of Biological SciencesTata Institute of Fundamental ResearchMumbaiMaharashtraIndia
| | - Sthitapranjya Pati
- Department of Biological SciencesTata Institute of Fundamental ResearchMumbaiMaharashtraIndia
| | - Amrita Bhattacharya
- Department of Biological SciencesTata Institute of Fundamental ResearchMumbaiMaharashtraIndia
| | - Karina Chaudhari
- Department of Biological SciencesTata Institute of Fundamental ResearchMumbaiMaharashtraIndia
| | - Vidita A. Vaidya
- Department of Biological SciencesTata Institute of Fundamental ResearchMumbaiMaharashtraIndia
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14
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Moutkine I, Quentin E, Guiard BP, Maroteaux L, Doly S. Heterodimers of serotonin receptor subtypes 2 are driven by 5-HT 2C protomers. J Biol Chem 2017; 292:6352-6368. [PMID: 28258217 DOI: 10.1074/jbc.m117.779041] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 03/02/2017] [Indexed: 11/06/2022] Open
Abstract
The serotonin receptor subtypes 2 comprise 5-HT2A, 5-HT2B, and 5-HT2C, which are Gαq-coupled receptors and display distinct pharmacological properties. Although co-expressed in some brain regions and involved in various neurological disorders, their functional interactions have not yet been studied. We report that 5-HT2 receptors can form homo- and heterodimers when expressed alone or co-expressed in transfected cells. Co-immunoprecipitation and bioluminescence resonance energy transfer studies confirmed that 5-HT2C receptors interact with either 5-HT2A or 5-HT2B receptors. Although heterodimerization with 5-HT2C receptors does not alter 5-HT2C Gαq-dependent inositol phosphate signaling, 5-HT2A or 5-HT2B receptor-mediated signaling was totally blunted. This feature can be explained by a dominance of 5-HT2C on 5-HT2A and 5-HT2B receptor binding; in 5-HT2C-containing heterodimers, ligands bind and activate the 5-HT2C protomer exclusively. This dominant effect on the associated protomer was also observed in neurons, supporting the physiological relevance of 5-HT2 receptor heterodimerization in vivo Accordingly, exogenous expression of an inactive form of the 5-HT2C receptor in the locus ceruleus is associated with decreased 5-HT2A-dependent noradrenergic transmission. These data demonstrate that 5-HT2 receptors can form functionally asymmetric heterodimers in vitro and in vivo that must be considered when analyzing the physiological or pathophysiological roles of serotonin in tissues where 5-HT2 receptors are co-expressed.
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Affiliation(s)
- Imane Moutkine
- From the INSERM UMR-S839, Paris 75005.,the Université Pierre et Marie Curie, Paris 75005.,the Institut du Fer à Moulin, Paris 75005
| | - Emily Quentin
- From the INSERM UMR-S839, Paris 75005.,the Université Pierre et Marie Curie, Paris 75005.,the Institut du Fer à Moulin, Paris 75005
| | - Bruno P Guiard
- the Research Center on Animal Cognition, Center for Integrative Biology, Université Paul Sabatier, UMR5169 CNRS, 118, Route de Narbonne, 31062, Toulouse Cedex 9, France
| | - Luc Maroteaux
- From the INSERM UMR-S839, Paris 75005, .,the Université Pierre et Marie Curie, Paris 75005.,the Institut du Fer à Moulin, Paris 75005
| | - Stephane Doly
- the Institut Cochin, INSERM U1016, CNRS UMR8104, Paris 75014, .,the Université Paris Descartes, Sorbonne Paris Cité, Paris 75014.,the Université Clermont Auvergne, INSERM, NEURO-DOL, F-63000 Clermont-Ferrand, and
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15
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Kurela L, Wallace M. Serotonergic Modulation of Sensory and Multisensory Processing in Superior Colliculus. Multisens Res 2017. [DOI: 10.1163/22134808-00002552] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The ability to integrate information across the senses is vital for coherent perception of and interaction with the world. While much is known regarding the organization and function of multisensory neurons within the mammalian superior colliculus (SC), very little is understood at a mechanistic level. One open question in this regard is the role of neuromodulatory networks in shaping multisensory responses. While the SC receives substantial serotonergic projections from the raphe nuclei, and serotonergic receptors are distributed throughout the SC, the potential role of serotonin (5-HT) signaling in multisensory function is poorly understood. To begin to fill this knowledge void, the current study provides physiological evidence for the influences of 5-HT signaling on auditory, visual and audiovisual responses of individual neurons in the intermediate and deep layers of the SC, with a focus on the 5HT2a receptor. Using single-unit extracellular recordings in combination with pharmacological methods, we demonstrate that alterations in 5HT2a receptor signaling change receptive field (RF) architecture as well as responsivity and integrative abilities of SC neurons when assessed at the level of the single neuron. In contrast, little changes were seen in the local field potential (LFP). These results are the first to implicate the serotonergic system in multisensory processing, and are an important step to understanding how modulatory networks mediate multisensory integration in the SC.
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Affiliation(s)
- LeAnne R. Kurela
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37232, USA
| | - Mark T. Wallace
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37232, USA
- Department of Hearing & Speech Sciences, Vanderbilt University, Nashville, TN 37232, USA
- Department of Psychology, Vanderbilt University, Nashville, TN 37232, USA
- Department of Psychiatry, Vanderbilt University, Nashville, TN 37232, USA
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16
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Prince LY, Bacon TJ, Tigaret CM, Mellor JR. Neuromodulation of the Feedforward Dentate Gyrus-CA3 Microcircuit. Front Synaptic Neurosci 2016; 8:32. [PMID: 27799909 PMCID: PMC5065980 DOI: 10.3389/fnsyn.2016.00032] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Accepted: 09/20/2016] [Indexed: 12/16/2022] Open
Abstract
The feedforward dentate gyrus-CA3 microcircuit in the hippocampus is thought to activate ensembles of CA3 pyramidal cells and interneurons to encode and retrieve episodic memories. The creation of these CA3 ensembles depends on neuromodulatory input and synaptic plasticity within this microcircuit. Here we review the mechanisms by which the neuromodulators aceylcholine, noradrenaline, dopamine, and serotonin reconfigure this microcircuit and thereby infer the net effect of these modulators on the processes of episodic memory encoding and retrieval.
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Affiliation(s)
- Luke Y Prince
- Centre for Synaptic Plasticity, School of Physiology, Pharmacology and Neuroscience, University of Bristol Bristol, UK
| | - Travis J Bacon
- Centre for Synaptic Plasticity, School of Physiology, Pharmacology and Neuroscience, University of Bristol Bristol, UK
| | - Cezar M Tigaret
- Centre for Synaptic Plasticity, School of Physiology, Pharmacology and Neuroscience, University of Bristol Bristol, UK
| | - Jack R Mellor
- Centre for Synaptic Plasticity, School of Physiology, Pharmacology and Neuroscience, University of Bristol Bristol, UK
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17
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Hegeman DJ, Hong ES, Hernández VM, Chan CS. The external globus pallidus: progress and perspectives. Eur J Neurosci 2016; 43:1239-65. [PMID: 26841063 PMCID: PMC4874844 DOI: 10.1111/ejn.13196] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 01/20/2016] [Accepted: 01/27/2016] [Indexed: 12/12/2022]
Abstract
The external globus pallidus (GPe) of the basal ganglia is in a unique and powerful position to influence processing of motor information by virtue of its widespread projections to all basal ganglia nuclei. Despite the clinical importance of the GPe in common motor disorders such as Parkinson's disease, there is only limited information about its cellular composition and organizational principles. In this review, recent advances in the understanding of the diversity in the molecular profile, anatomy, physiology and corresponding behaviour during movement of GPe neurons are described. Importantly, this study attempts to build consensus and highlight commonalities of the cellular classification based on existing but contentious literature. Additionally, an analysis of the literature concerning the intricate reciprocal loops formed between the GPe and major synaptic partners, including both the striatum and the subthalamic nucleus, is provided. In conclusion, the GPe has emerged as a crucial node in the basal ganglia macrocircuit. While subtleties in the cellular makeup and synaptic connection of the GPe create new challenges, modern research tools have shown promise in untangling such complexity, and will provide better understanding of the roles of the GPe in encoding movements and their associated pathologies.
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Affiliation(s)
- Daniel J Hegeman
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Ellie S Hong
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Vivian M Hernández
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - C Savio Chan
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
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18
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Venzi M, David F, Bellet J, Cavaccini A, Bombardi C, Crunelli V, Di Giovanni G. Role for serotonin2A (5-HT2A) and 2C (5-HT2C) receptors in experimental absence seizures. Neuropharmacology 2016; 108:292-304. [PMID: 27085605 PMCID: PMC4920646 DOI: 10.1016/j.neuropharm.2016.04.016] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 03/10/2016] [Accepted: 04/12/2016] [Indexed: 01/25/2023]
Abstract
Absence seizures (ASs) are the hallmark of childhood/juvenile absence epilepsy. Monotherapy with first-line anti-absence drugs only controls ASs in 50% of patients, indicating the need for novel therapeutic targets. Since serotonin family-2 receptors (5-HT2Rs) are known to modulate neuronal activity in the cortico-thalamo-cortical loop, the main network involved in AS generation, we investigated the effect of selective 5-HT2AR and 5-HT2CR ligands on ASs in the Genetic Absence Epilepsy Rats from Strasbourg (GAERS), a well established polygenic rat model of these non-convulsive seizures. GAERS rats were implanted with fronto-parietal EEG electrodes under general anesthesia, and their ASs were later recorded under freely moving conditions before and after intraperitoneal administration of various 5-HT2AR and 5-HT2CR ligands. The 5-HT2A agonist TCB-2 dose-dependently decreased the total time spent in ASs, an effect that was blocked by the selective 5-HT2A antagonist MDL11,939. Both MDL11,939 and another selective 5-HT2A antagonist (M100,907) increased the length of individual seizures when injected alone. The 5-HT2C agonists lorcaserin and CP-809,101 dose-dependently suppressed ASs, an effect blocked by the selective 5-HT2C antagonist SB 242984. In summary, 5-HT2ARs and 5-HT2CRs negatively control the expression of experimental ASs, indicating that selective agonists at these 5-HT2R subtypes might be potential novel anti-absence drugs. 5-HT2AR activation decreases absence seizures in GAERS. 5-HT2CR activation decreases absence seizures in GAERS. 5-HT2AR blockade increases absence seizures in GAERS. 5-HT2CR blockade does not affect absence seizures in GAERS.
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Affiliation(s)
- Marcello Venzi
- Neuroscience Division, School of Bioscience, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK
| | - François David
- Neuroscience Division, School of Bioscience, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK
| | - Joachim Bellet
- Werner Reichardt Centre for Integrative Neuroscience, Tuebingen University, Tuebingen, Germany
| | - Anna Cavaccini
- Neuroscience Division, School of Bioscience, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK
| | - Cristiano Bombardi
- University of Bologna, Department of Veterinary Medical Sciences, Bologna, Italy
| | - Vincenzo Crunelli
- Neuroscience Division, School of Bioscience, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK; Department of Physiology and Biochemistry, University of Malta, Malta.
| | - Giuseppe Di Giovanni
- Neuroscience Division, School of Bioscience, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK; Department of Physiology and Biochemistry, University of Malta, Malta.
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19
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Chagraoui A, Thibaut F, Skiba M, Thuillez C, Bourin M. 5-HT2C receptors in psychiatric disorders: A review. Prog Neuropsychopharmacol Biol Psychiatry 2016; 66:120-135. [PMID: 26739950 DOI: 10.1016/j.pnpbp.2015.12.006] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 12/25/2015] [Accepted: 12/26/2015] [Indexed: 12/26/2022]
Abstract
5-HT2Rs have a different genomic organization from other 5-HT2Rs. 5HT2CR undergoes post-transcriptional pre-mRNA editing generating diversity among RNA transcripts. Selective post-transcriptional editing could be involved in the pathophysiology of psychiatric disorders through impairment in G-protein interactions. Moreover, it may influence the therapeutic response to agents such as atypical antipsychotic drugs. Additionally, 5-HT2CR exhibits alternative splicing. Central serotonergic and dopaminergic systems interact to modulate normal and abnormal behaviors. Thus, 5HT2CR plays a crucial role in psychiatric disorders. 5HT2CR could be a relevant pharmacological target in the treatment of neuropsychiatric disorders. The development of drugs that specifically target 5-HT2C receptors will allow for better understanding of their involvement in the pathophysiology of psychiatric disorders including schizophrenia, anxiety, and depression. Among therapeutic means currently available, most drugs used to treat highly morbid psychiatric diseases interact at least partly with 5-HT2CRs. Pharmacologically, 5HT2CRs, have the ability to generate differentially distinct response signal transduction pathways depending on the type of 5HT2CR agonist. Although this receptor property has been clearly demonstrated, in vitro, the eventual beneficial impact of this property opens new perspectives in the development of agonists that could activate signal transduction pathways leading to better therapeutic efficiency with fewer adverse effects.
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Affiliation(s)
- A Chagraoui
- Inserm U982, Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, Institute for Research and Innovation in Biomedicine, Normandy University, France; Department of Medical Biochemistry, Rouen University Hospital, Rouen, France.
| | - F Thibaut
- Department of Psychiatry, University Hospital Cochin (site Tarnier), University of Paris-Descartes and INSERM U 894 Laboratory of Psychiatry and Neurosciences, Paris, France
| | - M Skiba
- Inserm U982, Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, Institute for Research and Innovation in Biomedicine, Normandy University, France
| | - C Thuillez
- Department of Pharmacology, Rouen University Hospital, Rouen, France; INSERM U1096, Laboratory of New Pharmacological Targets for Endothelial Protection and Heart Failure, Institute for Research and Innovation in Biomedicine, Normandy University, France
| | - M Bourin
- EA 3256 Neurobiology of Anxiety and Depression, Faculté de Médecine, BP 53508, 1 rue Gaston Veil, F44035 Nantes Cedex 01, France
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20
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Crunelli V, Di Giovanni G. Differential Control by 5-HT and 5-HT1A, 2A, 2C Receptors of Phasic and Tonic GABAA Inhibition in the Visual Thalamus. CNS Neurosci Ther 2015; 21:967-70. [PMID: 26555767 PMCID: PMC4973707 DOI: 10.1111/cns.12480] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 10/15/2015] [Accepted: 10/16/2015] [Indexed: 11/29/2022] Open
Affiliation(s)
- Vincenzo Crunelli
- Neuroscience Division, School of Bioscience, Cardiff University, Cardiff, UK.,Department of Physiology and Biochemistry, University of Malta, Msida, Malta
| | - Giuseppe Di Giovanni
- Neuroscience Division, School of Bioscience, Cardiff University, Cardiff, UK.,Department of Physiology and Biochemistry, University of Malta, Msida, Malta
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21
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Joo K, Rhie DJ, Jang HJ. Enhancement of GluN2B Subunit-Containing NMDA Receptor Underlies Serotonergic Regulation of Long-Term Potentiation after Critical Period in the Rat Visual Cortex. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2015; 19:523-31. [PMID: 26557019 PMCID: PMC4637355 DOI: 10.4196/kjpp.2015.19.6.523] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 08/18/2015] [Accepted: 08/19/2015] [Indexed: 11/15/2022]
Abstract
Serotonin [5-hydroxytryptamine (5-HT)] regulates synaptic plasticity in the visual cortex. Although the effects of 5-HT on plasticity showed huge diversity depending on the ages of animals and species, it has been unclear how 5-HT can show such diverse effects. In the rat visual cortex, 5-HT suppressed long-term potentiation (LTP) at 5 weeks but enhanced LTP at 8 weeks. We speculated that this difference may originate from differential regulation of neurotransmission by 5-HT between the age groups. Thus, we investigated the effects of 5-HT on apha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR)-, γ-aminobutyric acid receptor type A (GABAAR)-, and N-methyl-D-aspartic acid receptor (NMDAR)-mediated neurotransmissions and their involvement in the differential regulation of plasticity between 5 and 8 weeks. AMPAR-mediated currents were not affected by 5-HT at both 5 and 8 weeks. GABAAR-mediated currents were enhanced by 5-HT at both age groups. However, 5-HT enhanced NMDAR-mediated currents only at 8 weeks. The enhancement of NMDAR-mediated currents appeared to be mediated by the enhanced function of GluN2B subunit-containing NMDAR. The enhanced GABAAR- and NMDAR-mediated neurotransmissions were responsible for the suppression of LTP at 5 weeks and the facilitation of LTP at 8 weeks, respectively. These results indicate that the effects of 5-HT on neurotransmission change with development, and the changes may underlie the differential regulation of synaptic plasticity between different age groups. Thus, the developmental changes in 5-HT function should be carefully considered while investigating the 5-HT-mediated metaplastic control of the cortical network.
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Affiliation(s)
- Kayoung Joo
- Department of Physiology, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea
| | - Duck-Joo Rhie
- Department of Physiology, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea. ; Catholic Neuroscience Institute, The Catholic University of Korea, Seoul 06591, Korea
| | - Hyun-Jong Jang
- Department of Physiology, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea. ; Catholic Neuroscience Institute, The Catholic University of Korea, Seoul 06591, Korea
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22
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Effects of prenatal stress and neonatal handling on anxiety, spatial learning and serotonergic system of male offspring mice. Neurosci Res 2015; 101:15-23. [PMID: 26163770 DOI: 10.1016/j.neures.2015.07.002] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 07/01/2015] [Accepted: 07/01/2015] [Indexed: 11/22/2022]
Abstract
Environmental factors during perinatal period have various effects on behavior. The present study examined the effects of prenatal stress and neonatal handling on anxiety and spatial learning of offspring. Prenatal stress increased anxiety-related behavior of adult offspring, whereas neonatal handling had no effect. In contrast, spatial learning was not affected by prenatal stress, but improved by neonatal handling in both prenatally stressed and non-stressed mice. Next, to elucidate possible brain mechanisms mediating effects of environmental factors on behavior, we focused on serotonin (5-HT) system in the frontal cortex and hippocampus which is involved in anxiety and learning. We examined effects of environmental factors on the mRNA expression of 5-HT1A, 5-HT2A and 5-HT2C receptors in the frontal cortex and hippocampus during postnatal period and adulthood. Both prenatal stress and neonatal handling altered the mRNA expression of 5-HT receptors. These effects were dependent on environmental factors, brain regions and developmental stages. In summary, the present study revealed that prenatal stress and neonatal handling had differential effects on anxiety and spatial learning of offspring, and concomitantly the expression of 5-HT receptors. It was also shown that the effects of prenatal stress on 5-HT system were recovered partially by neonatal handling.
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23
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García-Cabrerizo R, García-Fuster MJ. Chronic MDMA induces neurochemical changes in the hippocampus of adolescent and young adult rats: Down-regulation of apoptotic markers. Neurotoxicology 2015; 49:104-13. [DOI: 10.1016/j.neuro.2015.06.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 06/05/2015] [Accepted: 06/05/2015] [Indexed: 11/24/2022]
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24
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Guiard BP, Di Giovanni G. Central serotonin-2A (5-HT2A) receptor dysfunction in depression and epilepsy: the missing link? Front Pharmacol 2015; 6:46. [PMID: 25852551 PMCID: PMC4362472 DOI: 10.3389/fphar.2015.00046] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Accepted: 02/24/2015] [Indexed: 11/17/2022] Open
Abstract
5-Hydroxytryptamine 2A receptors (5-HT2A-Rs) are G-protein coupled receptors. In agreement with their location in the brain, they have been implicated not only in various central physiological functions including memory, sleep, nociception, eating and reward behaviors, but also in many neuropsychiatric disorders. Interestingly, a bidirectional link between depression and epilepsy is suspected since patients with depression and especially suicide attempters have an increased seizure risk, while a significant percentage of epileptic patients suffer from depression. Such epidemiological data led us to hypothesize that both pathologies may share common anatomical and neurobiological alteration of the 5-HT2A signaling. After a brief presentation of the pharmacological properties of the 5-HT2A-Rs, this review illustrates how these receptors may directly or indirectly control neuronal excitability in most networks involved in depression and epilepsy through interactions with the monoaminergic, GABAergic and glutamatergic neurotransmissions. It also synthetizes the preclinical and clinical evidence demonstrating the role of these receptors in antidepressant and antiepileptic responses.
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Affiliation(s)
- Bruno P Guiard
- CNRS, Centre de Recherches sur la Cognition Animale, UMR 5169, Toulouse France ; CNRS, Centre de Recherches sur la Cognition Animale Université de Toulouse 3, UMR 5169, Toulouse, France ; INSERM U1178 Team ≪Depression and Antidepressants≫ Faculté de Pharmacie Paris Sud, Châtenay-Malabry, France
| | - Giuseppe Di Giovanni
- Neurophysiology Unit, Laboratory for the Study of Neurological Disorders, Department of Physiology and Biochemistry, University of Malta, Msida Malta ; School of Biosciences, University of Cardiff, Cardiff UK
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25
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Oostland M, Buijink MR, Teunisse GM, von Oerthel L, Smidt MP, van Hooft JA. Distinct temporal expression of 5-HT(1A) and 5-HT(2A) receptors on cerebellar granule cells in mice. THE CEREBELLUM 2015; 13:491-500. [PMID: 24788088 PMCID: PMC4077297 DOI: 10.1007/s12311-014-0565-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Serotonin plays an important role of controlling the physiology of the cerebellum. However, serotonin receptor expression has not been fully studied in the developing cerebellum. We have recently shown that cerebellar granule cells transiently express 5-HT3 receptors. In the present study, we investigate expression of 5-HT1 and 5-HT2 receptors in the mouse cerebellum both during postnatal development and in juvenile mice. Here, we show for the first time that 5-HT1A and 5-HT2A receptors are present on cerebellar granule cells with a distinct temporal expression pattern: 5-HT1A receptors are expressed only during the first 2 weeks, while 5-HT2A receptor expression persists until at least 8 weeks after birth. Because of its prolonged expression pattern, we investigated the electrophysiological properties of the 5-HT2A receptor. 5-HT2A receptors expressed by cerebellar granule cells promote stability by reducing variability of the synaptic response, and they modulate the paired-pulse ratio of the parallel fibre-Purkinje cell synapse. Furthermore, pharmacological block of 5-HT2A receptors enhances short-term synaptic plasticity at the parallel fibre-Purkinje cell synapse. We thus show a novel role for serotonin in controlling function of the cerebellum via 5-HT2A receptors expressed by cerebellar granule cells.
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Affiliation(s)
- Marlies Oostland
- Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, P.O. box 94232, 1090 GE, Amsterdam, The Netherlands
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26
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Fujita S, Mizoguchi N, Aoki R, Cui Y, Koshikawa N, Kobayashi M. Cytoarchitecture-Dependent Decrease in Propagation Velocity of Cortical Spreading Depression in the Rat Insular Cortex Revealed by Optical Imaging. Cereb Cortex 2015; 26:1580-1589. [PMID: 25595184 DOI: 10.1093/cercor/bhu336] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Cortical spreading depression (SD) is a self-propagating wave of depolarization accompanied by a substantial disturbance of the ionic distribution between the intra- and extracellular compartments. Glial cells, including astrocytes, play critical roles in maintenance of the extracellular environment, including ionic distribution. Therefore, SD propagation in the cerebral cortex may depend on the density of astrocytes. The present study aimed to examine the profile of SD propagation in the insular cortex (IC), which is located between the neocortex and paleocortex and is where the density of astrocytes gradually changes. The velocity of SD propagation in the neocortex, including the somatosensory, motor, and granular insular cortices (5.7 mm/min), was higher than that (2.8 mm/min) in the paleocortex (agranular insular and piriform cortices). Around thick vessels, including the middle cerebral artery, SD propagation was frequently delayed and sometimes disappeared. Immunohistological analysis of glial fibrillary acidic protein (GFAP) demonstrated the sparse distribution of astrocytes in the somatosensory cortex and the IC dorsal to the rhinal fissure, whereas the ventral IC showed a higher density of astrocytes. These results suggest that cortical cytoarchitectonic features, which possibly involve the distribution of astrocytes, are crucial for regulating the velocity of SD propagation in the cerebral cortex.
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Affiliation(s)
- Satoshi Fujita
- Department of Pharmacology, Dental Research Center, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.,Division of Oral and Craniomaxillofacial Research, Dental Research Center, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan
| | - Naoko Mizoguchi
- Department of Pharmacology, Dental Research Center, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.,Division of Physiology, Department of Human Development and Fostering
| | - Ryuhei Aoki
- Department of Pharmacology, Dental Research Center, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.,Division of Oral and Maxillofacial Surgery, Department of Diagnostic and Therapeutic Sciences, Meikai University School of Dentistry, 1-1 Keyakidai, Sakado, Saitama 350-0283, Japan
| | - Yilong Cui
- Molecular Dynamics Imaging Unit, RIKEN Center for Life Science Technologies, 6-7-3 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan
| | - Noriaki Koshikawa
- Department of Pharmacology, Dental Research Center, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.,Division of Oral and Craniomaxillofacial Research, Dental Research Center, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan
| | - Masayuki Kobayashi
- Department of Pharmacology, Dental Research Center, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.,Division of Oral and Craniomaxillofacial Research, Dental Research Center, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.,Molecular Dynamics Imaging Unit, RIKEN Center for Life Science Technologies, 6-7-3 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan
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27
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Orban G, Bombardi C, Marino Gammazza A, Colangeli R, Pierucci M, Pomara C, Pessia M, Bucchieri F, Arcangelo B, Smolders I, De Deurwaerdère P, Di Giovanni G. Role(s) of the 5-HT2C receptor in the development of maximal dentate activation in the hippocampus of anesthetized rats. CNS Neurosci Ther 2014; 20:651-61. [PMID: 24935789 PMCID: PMC6493041 DOI: 10.1111/cns.12285] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 04/23/2014] [Accepted: 04/26/2014] [Indexed: 11/29/2022] Open
Abstract
AIMS Substantial evidence indicates that 5-HT2C receptors are involved in the control of neuronal network excitability and in seizure pathophysiology. Here, we have addressed the relatively unexplored relationship between temporal lobe epilepsy (TLE), the most frequent type of intractable epilepsy, and 5-HT2CRs. METHODS In this study, we investigated this issue using a model of partial complex (limbic) seizures in urethane-anesthetized rat, based on the phenomenon of maximal dentate activation (MDA) using 5-HT2C compounds, electrophysiology, immunohistochemistry, and western blotting techniques. RESULTS The 5-HT2C agonists mCPP (1 mg/kg, i.p) and lorcaserin (3 mg/kg, i.p), but not RO60-0175 (1-3 mg/kg i.p.), were antiepileptogenic reducing the MDA response duration. The selective 5-HT2C antagonist SB242084 (2 mg/kg, i.p) unveiled antiepileptogenic effects of RO60-0175 (3 mg/kg, i.p) but did not alter those induced by mCPP and lorcaserin. Compared with control rats, electrically stimulated rats showed an increase in glutamic acid decarboxylase levels and a heterogeneous decrease in 5-HT2CR immunoreactivity in different hippocampal areas. CONCLUSIONS In our animal model of TLE, mCPP and lorcaserin were anticonvulsant; likely acting on receptor subtypes other than 5-HT2C. Epileptogenesis induced early adaptive changes and reorganization in the 5-HT2CR and GABA systems.
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Affiliation(s)
- Gergely Orban
- Dipartimento di Biomedicina Sperimentale e Neuroscienze ClinicheUniversità degli Studi di PalermoPalermoItaly
- Istituto Euro‐Mediterraneo di Scienza e Tecnologia (IEMEST)PalermoItaly
| | - Cristiano Bombardi
- Department of Veterinary Medical ScienceUniversity of BolognaBolognaItaly
| | - Antonella Marino Gammazza
- Dipartimento di Biomedicina Sperimentale e Neuroscienze ClinicheUniversità degli Studi di PalermoPalermoItaly
- Istituto Euro‐Mediterraneo di Scienza e Tecnologia (IEMEST)PalermoItaly
| | - Roberto Colangeli
- Department of Physiology and BiochemistryUniversity of MaltaMsidaMalta
| | - Massimo Pierucci
- Istituto Euro‐Mediterraneo di Scienza e Tecnologia (IEMEST)PalermoItaly
- Department of Physiology and BiochemistryUniversity of MaltaMsidaMalta
| | - Cristoforo Pomara
- Department of AnatomyFaculty of Medicine and SurgeryUniversity of MaltaMsidaMalta
- Department of Forensic PathologyUniversity of FoggiaFoggiaItaly
| | - Mauro Pessia
- Department of Internal MedicineSection of Human PhysiologyUniversity of PerugiaPerugiaItaly
| | - Fabio Bucchieri
- Dipartimento di Biomedicina Sperimentale e Neuroscienze ClinicheUniversità degli Studi di PalermoPalermoItaly
- Istituto Euro‐Mediterraneo di Scienza e Tecnologia (IEMEST)PalermoItaly
| | - Benigno Arcangelo
- Dipartimento di Biomedicina Sperimentale e Neuroscienze ClinicheUniversità degli Studi di PalermoPalermoItaly
| | - Ilse Smolders
- Center for Neurosciences C4NVrije Universiteit BrusselBrusselsBelgium
| | | | - Giuseppe Di Giovanni
- Istituto Euro‐Mediterraneo di Scienza e Tecnologia (IEMEST)PalermoItaly
- Department of Physiology and BiochemistryUniversity of MaltaMsidaMalta
- School of BiosciencesCardiff UniversityCardiffUK
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28
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Shukla R, Watakabe A, Yamamori T. mRNA expression profile of serotonin receptor subtypes and distribution of serotonergic terminations in marmoset brain. Front Neural Circuits 2014; 8:52. [PMID: 24904298 PMCID: PMC4032978 DOI: 10.3389/fncir.2014.00052] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Accepted: 04/25/2014] [Indexed: 01/06/2023] Open
Abstract
To better understand serotonin function in the primate brain, we examined the mRNA expression patterns of all the 13 members of the serotonin receptor (5HTR) family, by in situ hybridization (ISH) and the distribution of serotonergic terminations by serotonin transporter (SERT) protein immunohistochemical analysis. Ten of the 13 5HTRs showed significant mRNA expressions in the marmoset brain. Our study shows several new features of the organization of serotonergic systems in the marmoset brain. (1) The thalamus expressed only a limited number of receptor subtypes compared with the cortex, hippocampus, and other subcortical regions. (2) In the cortex, there are layer-selective and area-selective mRNA expressions of 5HTRs. (3) Highly localized mRNA expressions of 5HT1F and 5HT3A were observed. (4) There was a conspicuous overlap of the mRNA expressions of receptor subtypes known to have somatodendritic localization of receptor proteins with dense serotonergic terminations in the visual cortex, the central lateral (CL) nucleus of the thalamus, the presubiculum, and the medial mammillary nucleus of the hypothalamus. This suggests a high correlation between serotonin availability and receptor expression at these locations. (5) The 5HTRs show differences in mRNA expression pattern between the marmoset and mouse cortices whereas the patterns of both the species were much similar in the hippocampus. We discuss the possible roles of 5HTRs in the marmoset brain revealed by the analysis of their overall mRNA expression patterns.
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Affiliation(s)
- Rammohan Shukla
- Division of Brain Biology, National Institute for Basic Biology Okazaki, Japan ; Department of Basic Biology, Graduate University for Advanced Studies (SOKENDAI) Okazaki, Japan
| | - Akiya Watakabe
- Division of Brain Biology, National Institute for Basic Biology Okazaki, Japan ; Department of Basic Biology, Graduate University for Advanced Studies (SOKENDAI) Okazaki, Japan
| | - Tetsuo Yamamori
- Division of Brain Biology, National Institute for Basic Biology Okazaki, Japan ; Department of Basic Biology, Graduate University for Advanced Studies (SOKENDAI) Okazaki, Japan
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29
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Bombardi C. Neuronal localization of the 5-HT2 receptor family in the amygdaloid complex. Front Pharmacol 2014; 5:68. [PMID: 24782772 PMCID: PMC3988395 DOI: 10.3389/fphar.2014.00068] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Accepted: 03/24/2014] [Indexed: 12/21/2022] Open
Abstract
The amygdaloid complex (or amygdala), a heterogeneous structure located in the medial portion of the temporal lobe, is composed of deep, superficial, and “remaining” nuclei. This structure is involved in the generation of emotional behavior, in the formation of emotional memories and in the modulation of the consolidation of explicit memories for emotionally arousing events. The serotoninergic fibers originating in the dorsal and medial raphe nuclei are critically involved in amygdalar functions. Serotonin (5-hydroxytryptamine, 5-HT) regulates amygdalar activity through the activation of the 5-HT2 receptor family, which includes three receptor subtypes: 5-HT2A, 5-HT2B, and 5-HT2C. The distribution and the functional activity of the 5-HT2 receptor family has been studied more extensively than that of the 5-HT2A receptor subtypes, especially in the deep nuclei. In these nuclei, the 5-HT2A receptor is expressed on both pyramidal and non-pyramidal neurons, and could play a critical role in the formation of emotional memories. However, the exact role of the 5-HT2A receptor subtypes, as well as that of the 5-HT2B and 5-HT2C receptor subtypes, in the modulation of the amygdalar microcircuits requires additional study. The present review reports data concerning the distribution and the functional roles of the 5-HT2 receptor family in the amygdala.
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Affiliation(s)
- Cristiano Bombardi
- Department of Veterinary Medical Sciences, University of Bologna Bologna, Italy
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30
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Ohtani A, Kozono N, Senzaki K, Shiga T. Serotonin 2A receptor regulates microtubule assembly and induces dynamics of dendritic growth cones in rat cortical neurons in vitro. Neurosci Res 2014; 81-82:11-20. [PMID: 24698813 DOI: 10.1016/j.neures.2014.03.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Revised: 03/19/2014] [Accepted: 03/19/2014] [Indexed: 10/25/2022]
Abstract
Serotonin (5-HT) regulates the development of cerebral cortex, but 5-HT receptors mediating the effects are poorly understood. We investigated roles of 5-HT2A receptor in dendritic growth cones using dissociation culture of rat cerebral cortex. Neurons at embryonic day 16 were cultured for 4 days and treated with 5-HT2A/2C receptor agonist (DOI) for 4h. DOI increased the size of growth cone periphery which was actin-rich and microtubule-associated protein 2-negative at the dendritic tip. The length increase of the growth cone periphery may be mediated by 5-HT2A receptor, because the 5-HT2A receptor antagonist reversed the effects of DOI. Moreover, the time-lapse analysis demonstrated the increase of morphological dynamics in dendritic growth cones by DOI. Next, to elucidate the mechanisms underlying the actions of 5-HT2A receptor in dendritic growth cones, we examined the cytoskeletal proteins, tyrosinated α-tubulin (Tyr-T; dynamic tubulin) and acetylated α-tubulin (Ace-T; stable tubulin). DOI increased the fluorescence intensity of Tyr-T, while decreased that of Ace-T in the dendritic growth cone periphery. These effects were reversed by the 5-HT2A receptor antagonist, suggesting that 5-HT2A receptor promotes microtubule dynamics. In summary, it was suggested that 5-HT2A receptor induces morphological changes and dynamics of dendritic growth cones through regulation of microtubule assembly.
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Affiliation(s)
- Akiko Ohtani
- University of Tsukuba, Graduate School of Comprehensive Human Sciences, 1-1-1 Tennodai, Tsukuba 305-8577, Japan
| | - Naoki Kozono
- University of Tsukuba, Graduate School of Comprehensive Human Sciences, 1-1-1 Tennodai, Tsukuba 305-8577, Japan
| | - Kouji Senzaki
- University of Tsukuba, Graduate School of Comprehensive Human Sciences, 1-1-1 Tennodai, Tsukuba 305-8577, Japan
| | - Takashi Shiga
- University of Tsukuba, Graduate School of Comprehensive Human Sciences, 1-1-1 Tennodai, Tsukuba 305-8577, Japan.
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31
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Madden AMK, Zup SL. Effects of developmental hyperserotonemia on juvenile play behavior, oxytocin and serotonin receptor expression in the hypothalamus are age and sex dependent. Physiol Behav 2014; 128:260-9. [PMID: 24530263 DOI: 10.1016/j.physbeh.2014.01.036] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Revised: 12/11/2013] [Accepted: 01/23/2014] [Indexed: 11/17/2022]
Abstract
There is a striking sex difference in the diagnosis of Autism Spectrum Disorder (ASD), such that males are diagnosed more often than females, usually in early childhood. Given that recent research has implicated elevated blood serotonin (hyperserotonemia) in perinatal development as a potential factor in the pathogenesis of ASD, we sought to evaluate the effects of developmental hyperserotonemia on social behavior and relevant brain morphology in juvenile males and females. Administration of 5-methoxytryptamine (5-MT) both pre- and postnatally was found to disrupt normal social play behavior in juveniles. In addition, alterations in the number of oxytocinergic cells in the lateral and medial paraventricular nucleus (PVN) were evident on postnatal day 18 (PND18) in 5-MT treated females, but not treated males. 5-MT treatment also changed the relative expression of 5-HT(1A) and 5-HT(2A) receptors in the PVN, in males at PND10 and in females at PND18. These data suggest that serotonin plays an organizing role in the development of the PVN in a sexually dimorphic fashion, and that elevated serotonin levels during perinatal development may disrupt normal organization, leading to neurochemical and behavioral changes. Importantly, these data also suggest that the inclusion of both juvenile males and females in studies will be necessary to fully understand the role of serotonin in development, especially in relation to ASD.
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MESH Headings
- Age Factors
- Animals
- Behavior, Animal/physiology
- Female
- Hypothalamus/drug effects
- Hypothalamus/metabolism
- Hypothalamus/physiology
- Male
- Paraventricular Hypothalamic Nucleus/drug effects
- Paraventricular Hypothalamic Nucleus/metabolism
- Paraventricular Hypothalamic Nucleus/physiology
- Play and Playthings
- Rats
- Rats, Sprague-Dawley/growth & development
- Receptor, Serotonin, 5-HT2A/biosynthesis
- Receptor, Serotonin, 5-HT2A/physiology
- Receptors, Oxytocin/biosynthesis
- Receptors, Oxytocin/physiology
- Receptors, Serotonin/biosynthesis
- Receptors, Serotonin/physiology
- Serotonin/blood
- Serotonin/pharmacology
- Sex Factors
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Affiliation(s)
- Amanda M K Madden
- Graduate Program in Developmental and Brain Sciences, University of Massachusetts Boston, Boston, MA 02125, USA; Psychology Department, University of Massachusetts Boston, Boston, MA 02125, USA
| | - Susan L Zup
- Graduate Program in Developmental and Brain Sciences, University of Massachusetts Boston, Boston, MA 02125, USA; Psychology Department, University of Massachusetts Boston, Boston, MA 02125, USA.
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32
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McCool BA, Christian DT, Fetzer JA, Chappell AM. Lateral/basolateral amygdala serotonin type-2 receptors modulate operant self-administration of a sweetened ethanol solution via inhibition of principal neuron activity. Front Integr Neurosci 2014; 8:5. [PMID: 24523680 PMCID: PMC3906593 DOI: 10.3389/fnint.2014.00005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 01/09/2014] [Indexed: 11/13/2022] Open
Abstract
The lateral/basolateral amygdala (BLA) forms an integral part of the neural circuitry controlling innate anxiety and learned fear. More recently, BLA dependent modulation of self-administration behaviors suggests a much broader role in the regulation of reward evaluation. To test this, we employed a self-administration paradigm that procedurally segregates “seeking” (exemplified as lever-press behaviors) from consumption (drinking) directed at a sweetened ethanol solution. Microinjection of the nonselective serotonin type-2 receptor agonist, alpha-methyl-5-hydroxytryptamine (α-m5HT) into the BLA reduced lever pressing behaviors in a dose-dependent fashion. This was associated with a significant reduction in the number of response-bouts expressed during non-reinforced sessions without altering the size of a bout or the rate of responding. Conversely, intra-BLA α-m5HT only modestly effected consumption-related behaviors; the highest dose reduced the total time spent consuming a sweetened ethanol solution but did not inhibit the total number of licks, number of lick bouts, or amount of solution consumed during a session. In vitro neurophysiological characterization of BLA synaptic responses showed that α-m5HT significantly reduced extracellular field potentials. This was blocked by the 5-HT2A/C antagonist ketanserin suggesting that 5-HT2-like receptors mediate the behavioral effect of α-m5HT. During whole-cell patch current-clamp recordings, we subsequently found that α-m5HT increased action potential threshold and hyperpolarized the resting membrane potential of BLA pyramidal neurons. Together, our findings show that the activation of BLA 5-HT2A/C receptors inhibits behaviors related to reward-seeking by suppressing BLA principal neuron activity. These data are consistent with the hypothesis that the BLA modulates reward-related behaviors and provides specific insight into BLA contributions during operant self-administration of a sweetened ethanol solution.
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Affiliation(s)
- Brian A McCool
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem NC, USA
| | - Daniel T Christian
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem NC, USA
| | - Jonathan A Fetzer
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem NC, USA
| | - Ann M Chappell
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem NC, USA
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Oostland M, van Hooft J. The role of serotonin in cerebellar development. Neuroscience 2013; 248:201-12. [DOI: 10.1016/j.neuroscience.2013.05.029] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Revised: 05/16/2013] [Accepted: 05/17/2013] [Indexed: 01/09/2023]
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Sustained impairment of α2A-adrenergic autoreceptor signaling mediates neurochemical and behavioral sensitization to amphetamine. Biol Psychiatry 2013; 74:90-8. [PMID: 23332355 DOI: 10.1016/j.biopsych.2012.11.029] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Revised: 11/09/2012] [Accepted: 11/29/2012] [Indexed: 11/20/2022]
Abstract
BACKGROUND In rodents, drugs of abuse induce locomotor hyperactivity, and repeating injections enhance this response. This effect, called behavioral sensitization, persists months after the last administration. It has been shown that behavioral sensitization to amphetamine develops parallel to an increased release of norepinephrine (NE) in the prefrontal cortex (PFC). METHODS Rats and mice were repeatedly treated with amphetamine (1 or 2 mg/kg intraperitoneally, respectively) to obtain sensitized animals. The NE release in the PFC was measured by microdialysis in freely moving mice (n = 55). Activity of locus coeruleus (LC) noradrenergic neurons was determined in anaesthetized rats (n = 15) by in vivo extracellular electrophysiology. The α2A-adrenergic autoreceptor (α2A-AR) expression was assessed by autoradiography on brain slices, and Gαi proteins expression was measured by western blot analysis of LC punches. RESULTS In sensitized rats LC neurons had a higher spontaneous firing rate, and clonidine-an α2A-adrenergic agonist-inhibited LC neuronal firing less efficiently than in control animals. Clonidine also induced lower levels of NE release in the PFC of sensitized mice. This desensitization was maintained by a lower density of Gαi1 and Gαi2 proteins in the LC of sensitized mice rather than weaker α2A-AR expression. Behavioral sensitization was facilitated by α2A-AR antagonist, efaroxan, during amphetamine injections and abolished by clonidine treatment. CONCLUSIONS Our data indicate that noradrenergic inhibitory feedback is impaired for at least 1 month in rats and mice repeatedly treated with amphetamine. This work highlights the key role of noradrenergic autoreceptor signaling in the persistent modifications induced by repeated amphetamine administration.
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Arrant AE, Coburn E, Jacobsen J, Kuhn CM. Lower anxiogenic effects of serotonin agonists are associated with lower activation of amygdala and lateral orbital cortex in adolescent male rats. Neuropharmacology 2013; 73:359-67. [PMID: 23774134 DOI: 10.1016/j.neuropharm.2013.05.030] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Revised: 04/22/2013] [Accepted: 05/14/2013] [Indexed: 01/30/2023]
Abstract
There has been controversy over use of selective serotonin reuptake inhibitors (SSRIs) to treat affective disorders in children and adolescents due to clinical reports of increased risk for suicidal ideation and behavior during treatment, and animal studies showing changes in adult anxiety- and depressive-like behaviors after repeated treatment during adolescence. However, the acute effect of serotonergic drugs on affective behavior during adolescence is poorly understood. We investigated serotonergic modulation of anxiety-like behavior in adolescent (PN28-32) and adult (PN67-73) male rats using the SSRI fluoxetine, the 5-HT(1A) agonist 8-OH DPAT, and the 5-HT₂ agonist mCPP. Acute treatment with fluoxetine (10 mg/kg, i.p.) produced greater anxiogenic effects in adults than adolescents in the light/dark (LD) test for anxiety-like behavior, but fluoxetine (2.5, 5, and 10 mg/kg, i.p.) increased extracellular serotonin in the medial prefrontal cortex similarly in both ages. Adults were also more sensitive to the anxiogenic effects of 8-OH DPAT (0.25 and 0.5 mg/kg, i.p.), but not mCPP (0.5 and 1 mg/kg, i.p.), in the LD test. Fluoxetine (10 mg/kg) stimulated greater increases in c-Fos expression across the extended amygdala in adults than in adolescents, and 8-OH DPAT (0.5 mg/kg) produced greater increases in c-Fos in the lateral orbital cortex and central nucleus of the amygdala in adults. These data show that lower anxiogenic effects of acute SSRIs in adolescents are associated with lesser activation of cortical and amygdala brain regions. This immaturity could contribute to the different profile of behavioral effects observed in adolescents and adults treated with SSRIs.
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Affiliation(s)
- Andrew E Arrant
- Department of Pharmacology & Cancer Biology, Duke University Medical Center, Durham, NC 27710, USA
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36
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Li L, Qiu G, Ding S, Zhou FM. Serotonin hyperinnervation and upregulated 5-HT2A receptor expression and motor-stimulating function in nigrostriatal dopamine-deficient Pitx3 mutant mice. Brain Res 2012; 1491:236-50. [PMID: 23159831 DOI: 10.1016/j.brainres.2012.11.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 10/29/2012] [Accepted: 11/08/2012] [Indexed: 10/27/2022]
Abstract
The striatum receives serotonin (5-hydroxytryptamine, 5-HT) innervation and expresses 5-HT2A receptors (5-HT2ARs) and other 5-HT receptors, raising the possibility that the striatal 5-HT system may undergo adaptive changes after chronic severe dopamine (DA) loss and contribute to the function and dysfunction of the striatum. Here we show that in transcription factor Pitx3 gene mutant mice with a selective, severe DA loss in the dorsal striatum mimicking the DA denervation in late Parkinson's disease (PD), both the 5-HT innervation and the 5-HT2AR mRNA expression were increased in the dorsal striatum. Functionally, while having no detectable motor effect in wild type mice, the 5-HT2R agonist 2,5-dimethoxy-4-iodoamphetamine increased both the baseline and l-dopa-induced normal ambulatory and dyskinetic movements in Pitx3 mutant mice, whereas the selective 5-HT2AR blocker volinanserin had the opposite effects. These results demonstrate that Pitx3 mutant mice are a convenient and valid mouse model to study the compensatory 5-HT upregulation following the loss of the nigrostriatal DA projection and that the upregulated 5-HT2AR function in the DA deficient dorsal striatum may enhance both normal and dyskinetic movements.
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Affiliation(s)
- Li Li
- Department of Pharmacology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA
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37
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Arrant AE, Jemal H, Kuhn CM. Adolescent male rats are less sensitive than adults to the anxiogenic and serotonin-releasing effects of fenfluramine. Neuropharmacology 2012; 65:213-22. [PMID: 23103347 DOI: 10.1016/j.neuropharm.2012.10.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 10/14/2012] [Accepted: 10/18/2012] [Indexed: 11/30/2022]
Abstract
Risk taking behavior increases during adolescence, which is also a critical period for the onset of drug abuse. The central serotonergic system matures during the adolescent period, and its immaturity during early adolescence may contribute to adolescent risk taking, as deficits in central serotonergic function have been associated with impulsivity, aggression, and risk taking. We investigated serotonergic modulation of behavior and presynaptic serotonergic function in adult (67-74 days old) and adolescent (28-34 days old) male rats. Fenfluramine (2 mg/kg, i.p.) produced greater anxiogenic effects in adult rats in both the light/dark and elevated plus maze tests for anxiety-like behavior, and stimulated greater increases in extracellular serotonin in the adult medial prefrontal cortex (mPFC) (1, 2.5, and 10 mg/kg, i.p.). Local infusion of 100 mM potassium chloride into the mPFC also stimulated greater serotonin efflux in adult rats. Adult rats had higher tissue serotonin content than adolescents in the prefrontal cortex, amygdala, and hippocampus, but the rate of serotonin synthesis was similar between age groups. Serotonin transporter (SERT) immunoreactivity and SERT radioligand binding were comparable between age groups in all three brain regions. These data suggest that lower tissue serotonin stores in adolescents limit fenfluramine-stimulated serotonin release and so contribute to the lesser anxiogenic effects of fenfluramine.
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Affiliation(s)
- Andrew E Arrant
- Department of Pharmacology & Cancer Biology, Duke University, Room 100B Research Park Building 2, Box 3813, Duke University Medical Center, Durham, NC 27710, USA
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38
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Herrick-Davis K, Grinde E, Lindsley T, Cowan A, Mazurkiewicz JE. Oligomer size of the serotonin 5-hydroxytryptamine 2C (5-HT2C) receptor revealed by fluorescence correlation spectroscopy with photon counting histogram analysis: evidence for homodimers without monomers or tetramers. J Biol Chem 2012; 287:23604-14. [PMID: 22593582 PMCID: PMC3390635 DOI: 10.1074/jbc.m112.350249] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Revised: 04/05/2012] [Indexed: 11/06/2022] Open
Abstract
Fluorescence correlation spectroscopy (FCS) and photon counting histogram (PCH) are techniques with single molecule sensitivity that are well suited for examining the biophysical properties of protein complexes in living cells. In the present study, FCS and PCH were applied to determine the diffusion coefficient and oligomeric size of G-protein-coupled receptors. FCS was used to record fluctuations in fluorescence intensity arising from fluorescence-tagged 5-hydroxytryptamine 2C (5-HT(2C)) receptors diffusing within the plasma membrane of HEK293 cells and rat hippocampal neurons. Autocorrelation analysis yielded diffusion coefficients ranging from 0.8 to 1.2 μm(2)/s for fluorescence-tagged receptors. Because the molecular brightness of a fluorescent protein is directly proportional to the number of fluorescent proteins traveling together within a protein complex, it can be used to determine the oligomeric size of the protein complex. FCS and PCH analysis of fluorescence-tagged 5-HT(2C) receptors provided molecular brightness values that were twice that of GFP and YFP monomeric controls, similar to a dimeric GFP control, and unaltered by 5-HT. Bimolecular fluorescence complementation of the N- and C-terminal halves of YFP attached to 5-HT(2C) receptors was observed in endoplasmic reticulum/Golgi and plasma membranes with a brightness equal to monomeric YFP. When GFP-tagged 5-HT(2C) receptors were co-expressed with a large excess of untagged, non-fluorescent 5-HT(2C) receptors, the molecular brightness was reduced by half. PCH analysis of the FCS data were best described by a one-component dimer model without monomers or tetramers. Therefore, it is concluded that 5-HT(2C) receptors freely diffusing within the plasma membrane are dimeric.
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MESH Headings
- Animals
- Cell Membrane/drug effects
- Cell Membrane/metabolism
- Cells, Cultured
- Diffusion/drug effects
- Endoplasmic Reticulum/metabolism
- Fluorescence
- Golgi Apparatus/metabolism
- Green Fluorescent Proteins/chemistry
- Green Fluorescent Proteins/genetics
- Green Fluorescent Proteins/metabolism
- HEK293 Cells
- Hippocampus/cytology
- Humans
- Luminescent Proteins/chemistry
- Luminescent Proteins/genetics
- Luminescent Proteins/metabolism
- Microscopy, Confocal
- Mutation
- Neurons/cytology
- Neurons/drug effects
- Neurons/metabolism
- Protein Multimerization
- Protein Transport/drug effects
- Rats
- Rats, Sprague-Dawley
- Receptor, Serotonin, 5-HT2C/chemistry
- Receptor, Serotonin, 5-HT2C/genetics
- Receptor, Serotonin, 5-HT2C/metabolism
- Serotonin/pharmacology
- Spectrometry, Fluorescence/methods
- Transfection
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Affiliation(s)
- Katharine Herrick-Davis
- Center for Neuropharmacology and Neuroscience, Albany Medical College, Albany, New York 12208, USA.
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Berumen LC, Rodríguez A, Miledi R, García-Alcocer G. Serotonin receptors in hippocampus. ScientificWorldJournal 2012; 2012:823493. [PMID: 22629209 PMCID: PMC3353568 DOI: 10.1100/2012/823493] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 12/08/2011] [Indexed: 11/21/2022] Open
Abstract
Serotonin is an ancient molecular signal and a recognized neurotransmitter brainwide distributed with particular presence in hippocampus. Almost all serotonin receptor subtypes are expressed in hippocampus, which implicates an intricate modulating system, considering that they can be localized as autosynaptic, presynaptic, and postsynaptic receptors, even colocalized within the same cell and being target of homo- and heterodimerization. Neurons and glia, including immune cells, integrate a functional network that uses several serotonin receptors to regulate their roles in this particular part of the limbic system.
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Affiliation(s)
- Laura Cristina Berumen
- Facultad de Química, Universidad Autónoma de Querétaro, Centro Universitario S/N, Cerro de las Campanas, Querétaro 76010, Mexico
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40
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Park SW, Jang HJ, Cho KH, Kim MJ, Yoon SH, Rhie DJ. Developmental Switch of the Serotonergic Role in the Induction of Synaptic Long-term Potentiation in the Rat Visual Cortex. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2012; 16:65-70. [PMID: 22416222 PMCID: PMC3298828 DOI: 10.4196/kjpp.2012.16.1.65] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Revised: 02/08/2012] [Accepted: 02/16/2012] [Indexed: 11/15/2022]
Abstract
Synaptic long-term potentiation (LTP) and long-term depression (LTD) have been studied as mechanisms of ocular dominance plasticity in the rat visual cortex. Serotonin (5-hydroxytryptamine, 5-HT) inhibits the induction of LTP and LTD during the critical period of the rat visual cortex (postnatal 3~5 weeks). However, in adult rats, the increase in 5-HT level in the brain by the administration of the selective serotonin reuptake inhibitor (SSRI) fluoxetine reinstates ocular dominance plasticity and LTP in the visual cortex. Here, we investigated the effect of 5-HT on the induction of LTP in the visual cortex obtained from 3- to 10-week-old rats. Field potentials in layer 2/3, evoked by the stimulation of underlying layer 4, was potentiated by theta-burst stimulation (TBS) in 3- and 5-week-old rats, then declined to the baseline level with aging to 10 weeks. Whereas 5-HT inhibited the induction of LTP in 5-week-old rats, it reinstated the induction of N-methyl-D-aspartate receptor (NMDA)-dependent LTP in 8- and 10-week-old rats. Moreover, the selective SSRI citalopram reinstated LTP. The potentiating effect of 5-HT at 8 weeks of age was mediated by the activation of 5-HT2 receptors, but not by the activation of either 5-HT1A or 5-HT3 receptors. These results suggested that the effect of 5-HT on the induction of LTP switches from inhibitory in young rats to facilitatory in adult rats.
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Affiliation(s)
- Sung-Won Park
- Department of Physiology, College of Medicine, The Catholic University of Korea, Seoul 137-701, Korea
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41
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Bigford GE, Chaudhry NS, Keane RW, Holohean AM. 5-Hydroxytryptamine 5HT2C receptors form a protein complex with N-methyl-D-aspartate GluN2A subunits and activate phosphorylation of Src protein to modulate motoneuronal depolarization. J Biol Chem 2012; 287:11049-59. [PMID: 22291020 DOI: 10.1074/jbc.m111.277806] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
N-Methyl-D-aspartate (NMDA)-gated ion channels are known to play a critical role in motoneuron depolarization, but the molecular mechanisms modulating NMDA activation in the spinal cord are not well understood. This study demonstrates that activated 5HT2C receptors enhance NMDA depolarizations recorded electrophysiologically from motoneurons. Pharmacological studies indicate involvement of Src tyrosine kinase mediates 5HT2C facilitation of NMDA. RT-PCR analysis revealed edited forms of 5HT2C were present in mammalian spinal cord, indicating the availability of G-protein-independent isoforms. Spinal cord neurons treated with the 5HT2C agonist MK 212 showed increased Src(Tyr-416) phosphorylation in a dose-dependent manner thus verifying that Src is activated after treatment. In addition, 5HT2C antagonists and tyrosine kinase inhibitors blocked 5HT2C-mediated Src(Tyr-416) phosphorylation and also enhanced NMDA-induced motoneuron depolarization. Co-immunoprecipitation of synaptosomal fractions showed that GluN2A, 5HT2C receptors, and Src tyrosine kinase form protein associations in synaptosomes. Moreover, immunohistochemical analysis demonstrated GluN2A and 5HT2C receptors co-localize on the processes of spinal neurons. These findings reveal that a distinct multiprotein complex links 5-hydroxytryptamine-activated intracellular signaling events with NMDA-mediated functional activity.
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Affiliation(s)
- Gregory E Bigford
- Department of Physiology and Biophysics, University of Miami Miller School of Medicine, Miami, Florida 33101, USA
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42
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Jang HJ, Cho KH, Park SW, Kim MJ, Yoon SH, Rhie DJ. Layer-specific serotonergic facilitation of IPSC in layer 2/3 pyramidal neurons of the visual cortex. J Neurophysiol 2011; 107:407-16. [PMID: 22013240 DOI: 10.1152/jn.00535.2011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Serotonin (5-hydroxytryptamine, 5-HT) inhibits the induction of long-term synaptic plasticity in layer 2/3 of the visual cortex at the end of its critical period in rats. However, the cellular and molecular mechanisms remain unclear. Since inhibitory influence is crucial in the induction of synaptic plasticity, the effect of 5-HT on inhibitory transmission was investigated in layer 2/3 pyramidal neurons of the primary visual cortex. The amplitude of inhibitory postsynaptic current (IPSC), but not excitatory postsynaptic current, evoked by stimulation of the underlying layer 4, was increased by ∼20% with a bath application of 5-HT. The amplitude of miniature IPSC was also increased by the application of 5-HT, while the paired-pulse ratio was not changed. The facilitating effect of 5-HT on IPSC was mediated by the activation of 5-HT(2) receptors. An increase in intracellular Ca(2+) via release from inositol 1,4,5-trisphosphate (IP(3))-sensitive stores, which was confirmed by confocal Ca(2+) imaging, and activation of Ca(2+)/calmodulin-dependent kinase II (CaMKII) were involved in the facilitation of IPSC by 5-HT. However, 5-HT failed to facilitate IPSC evoked by the stimulation of layer 1. These results suggest that activation of 5-HT(2) receptors releases intracellular Ca(2+) via IP(3)-sensitive stores, which facilitates GABA(A)ergic transmission via the activation of CaMKII in layer 2/3 pyramidal neurons of the visual cortex in a layer-specific manner. Thus facilitation of inhibitory transmission by 5-HT might be involved in regulating the information flow and the induction of long-term synaptic plasticity, in a pathway-specific manner.
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Affiliation(s)
- Hyun-Jong Jang
- Dept. of Physiology, College of Medicine, Catholic Univ. of Korea, 505 Banpo-dong, Seocho-gu, Seoul 137-701, Republic of Korea
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Jitsuki S, Takemoto K, Kawasaki T, Tada H, Takahashi A, Becamel C, Sano A, Yuzaki M, Zukin RS, Ziff EB, Kessels HW, Takahashi T. Serotonin mediates cross-modal reorganization of cortical circuits. Neuron 2011; 69:780-92. [PMID: 21338886 DOI: 10.1016/j.neuron.2011.01.016] [Citation(s) in RCA: 109] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/24/2010] [Indexed: 11/26/2022]
Abstract
Loss of one type of sensory input can cause improved functionality of other sensory systems. Whereas this form of plasticity, cross-modal plasticity, is well established, the molecular and cellular mechanisms underlying it are still unclear. Here, we show that visual deprivation (VD) increases extracellular serotonin in the juvenile rat barrel cortex. This increase in serotonin levels facilitates synaptic strengthening at layer 4 to layer 2/3 synapses within the barrel cortex. Upon VD, whisker experience leads to trafficking of the AMPA-type glutamate receptors (AMPARs) into these synapses through the activation of ERK and increased phosphorylation of AMPAR subunit GluR1 at the juvenile age when natural whisker experience no longer induces synaptic GluR1 delivery. VD thereby leads to sharpening of the functional whisker-barrel map at layer 2/3. Thus, sensory deprivation of one modality leads to serotonin release in remaining modalities, facilitates GluR1-dependent synaptic strengthening, and refines cortical organization.
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Affiliation(s)
- Susumu Jitsuki
- Yokohama City University Graduate School of Medicine, Department of Physiology, Yokohama 236-0004, Japan
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Rodríguez JJ, Noristani HN, Hoover WB, Linley SB, Vertes RP. Serotonergic projections and serotonin receptor expression in the reticular nucleus of the thalamus in the rat. Synapse 2011; 65:919-28. [PMID: 21308802 DOI: 10.1002/syn.20920] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Accepted: 01/24/2011] [Indexed: 11/11/2022]
Abstract
The reticular nucleus (RT) of the thalamus, a thin sheet of GABAergic neurons located between the external medullary lamina and the internal capsule of the thalamus, has functionally distinct afferent and efferent connections with thalamic nuclei, the neocortex, the basal forebrain and the brainstem. RT is critically positioned to rhythmically pace thalamocortical networks leading to the generation of spindle activity during the early phases of sleep and during absence (spike-wave) seizures. Serotonin, acting on 5-HT(1A) receptors on parvalbumin-containing cells of RT, has been implicated in this rhythmicity. However, the precise source(s) of 5-HT afferents to the RT remains to be determined. In the present study, we injected the retrograde tracer, Fluorogold, into dorsal and ventral regions of RT to determine the origins of raphe input to RT. We further characterized the distribution of 5-HT fibers to RT by using immunohistochemistry for 5-HT and for the 5HT transporter (SERT) detection. Finally, we described the presence of the two major postsynaptic 5-HT receptors in RT, 5-HT(1A) and 5-HT(2A) receptors. Our results show that the dorsal raphe nucleus and the supralemniscal nucleus (B9) of the midbrain are the principal sources of raphe projections to RT. In addition, serotonergic fibers (5-HT and SERT positive) were richly distributed throughout RT, and 5-HT(1A) and 5-HT(2A) receptors were highly expressed on RT neurons and dendrites. These findings suggest a significant 5-HT modulatory influence on GABAergic neurons of RT in the control of rhythmical (or spindle) activity in thalamocortical systems directly associated with sleep and possibly with absence seizures.
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Affiliation(s)
- José J Rodríguez
- IKERBASQUE, Basque Foundation for Science, 48011, Bilbao, Spain.
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45
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Coulon P, Kanyshkova T, Broicher T, Munsch T, Wettschureck N, Seidenbecher T, Meuth SG, Offermanns S, Pape HC, Budde T. Activity Modes in Thalamocortical Relay Neurons are Modulated by G(q)/G(11) Family G-proteins - Serotonergic and Glutamatergic Signaling. Front Cell Neurosci 2010; 4:132. [PMID: 21267426 PMCID: PMC3024565 DOI: 10.3389/fncel.2010.00132] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2009] [Accepted: 09/28/2010] [Indexed: 11/13/2022] Open
Abstract
In thalamocortical relay (TC) neurons, G-protein-coupled receptors play an important part in the control of activity modes. A conditional Gα(q) knockout on the background of a constitutive Gα(11) knockout (Gα(q)/Gα(11) (-/-)) was used to determine the contribution of Gq/G11 family G-proteins to metabotropic serotonin (5-HT) and glutamate (Glu) function in the dorsal part of the lateral geniculate nucleus (dLGN). In control mice, current clamp recordings showed that α-m-5-HT induced a depolarization of V(rest) which was sufficient to suppress burst firing. This depolarization was concentration-dependent (100 μM: +6 ± 1 mV, n = 10; 200 μM: +10 ± 1 mV, n = 7) and had a conditioning effect on the activation of other Gα(q)-mediated pathways. The depolarization was significantly reduced in Gα(q)/Gα(11) (-/-) (100 μM: 3 ± 1 mV, n = 11; 200 μM: 5 ± 1 mV, n = 6) and was apparently insufficient to suppress burst firing. Activating Gα(q)-coupled muscarinic receptors affected the magnitude of α-m-5-HT-induced effects in a reciprocal manner. Furthermore, the depolarizing effect of mGluR1 agonists was significantly reduced in Gα(q)/Gα(11) (-/-) mice. Immunohistochemical stainings revealed binding of 5-HT(2C)R- and mGluR1α-, but not of 5-HT(2A)R-specific antibodies in the dLGN of Gα(q)/Gα(11) (-/-) mice. In conclusion, these findings demonstrate that transmitters of ascending brainstem fibers and corticofugal fibers both signal via a central element in the form of Gq/G11-mediated pathways to control activity modes in the TC system.
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Affiliation(s)
- Philippe Coulon
- Institut für Physiologie I, Westfälische Wilhelms-Universität Münster Münster, Germany
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Roles of serotonin 5-HT3 receptor in the formation of dendrites and axons in the rat cerebral cortex: An in vitro study. Neurosci Res 2010; 66:22-9. [DOI: 10.1016/j.neures.2009.09.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 09/09/2009] [Accepted: 09/14/2009] [Indexed: 11/17/2022]
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Tohda M, Hang PNT, Matsumoto K. Developmental changes in serotonin 2C receptor mRNA editing in the rat cerebral cortex and primary cultured cortical neurons. Biol Pharm Bull 2009; 32:289-92. [PMID: 19182391 DOI: 10.1248/bpb.32.289] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Serotonin 2C receptor (5-HT2CR) mRNA has been reported to receive editing at 5 nucleotide positions (named sites A-E) which are located inconsecutively on the nucleotide sequence encoding the 2nd intracellular loop of the receptor protein. To clarify the physiological role of 5-HT2CR mRNA editing, we investigated developmental changes in editing frequencies at sites A-E in the rat cerebral cortex and primary cultured cortical neurons. The editing at sites A and B increased in parallel with the rat brain development and reached a plateau of 80-100% frequency at postnatal days 1-3. Although editing frequency at site C was low compared to those detected at other sites except site E during a developmental period, it reached the maximal value of 30% during a first 7-d period after birth and then decreased gradually to the negligible level at PN49. Site D exhibited almost constant susceptibility (about 60%) to editing, while no editing at site E was occurred during rat brain development. Similar changes during development in editing frequencies at these sites were observed in primary cultured cortical cells during the cultivation period. These findings indicated that editing sites A-D on 5-HT2CR mRNA have different susceptibility and that the frequencies at these sites are not always constant during development.
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Affiliation(s)
- Michihisa Tohda
- Division of Medicinal Pharmacology, Institute of Natural Medicine University of Toyama, Toyama, Japan. tohdam@inm.-u-toyama.ac.jp
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Basura GJ, Abbas AI, O’Donohue H, Lauder JM, Roth BL, Walker PD, Manis PB. Ontogeny of serotonin and serotonin2A receptors in rat auditory cortex. Hear Res 2008; 244:45-50. [PMID: 18718516 PMCID: PMC2943586 DOI: 10.1016/j.heares.2008.07.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2008] [Revised: 06/12/2008] [Accepted: 07/09/2008] [Indexed: 11/23/2022]
Abstract
Maturation of the mammalian cerebral cortex is, in part, dependent upon multiple coordinated afferent neurotransmitter systems and receptor-mediated cellular linkages during early postnatal development. Given that serotonin (5-HT) is one such system, the present study was designed to specifically evaluate 5-HT tissue content as well as 5-HT(2A) receptor protein levels within the developing auditory cortex (AC). Using high performance liquid chromatography (HPLC), 5-HT and the metabolite, 5-hydroxyindoleacetic acid (5-HIAA), was measured in isolated AC, which demonstrated a developmental dynamic, reaching young adult levels early during the second week of postnatal development. Radioligand binding of 5-HT(2A) receptors with the 5-HT(2A/2C) receptor agonist, (125)I-DOI ((+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane HCl; in the presence of SB206553, a selective 5-HT(2C) receptor antagonist, also demonstrated a developmental trend, whereby receptor protein levels reached young adult levels at the end of the first postnatal week (P8), significantly increased at P10 and at P17, and decreased back to levels not significantly different from P8 thereafter. Immunocytochemical labeling of 5-HT(2A) receptors and confocal microscopy revealed that 5-HT(2A) receptors are largely localized on layer II/III pyramidal cell bodies and apical dendrites within AC. When considered together, the results of the present study suggest that 5-HT, likely through 5-HT(2A) receptors, may play an important role in early postnatal AC development.
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Affiliation(s)
- Gregory J. Basura
- Department of Otolaryngology/Head and Neck Surgery; The University of North Carolina at Chapel Hill; Chapel Hill North Carolina
| | - Atheir I. Abbas
- Department of Biochemistry, Case Western Reserve University School of Medicine, Cleveland, Ohio
| | - Heather O’Donohue
- Department of Otolaryngology/Head and Neck Surgery; The University of North Carolina at Chapel Hill; Chapel Hill North Carolina
| | - Jean M. Lauder
- Department of Cell and Developmental Biology; The University of North Carolina at Chapel Hill; Chapel Hill North Carolina
| | - Bryan L. Roth
- Department of Biochemistry, Case Western Reserve University School of Medicine, Cleveland, Ohio
- Department of Pharmacology; The University of North Carolina at Chapel Hill; Chapel Hill North Carolina
| | - Paul D. Walker
- Department of Anatomy and Cell Biology; Wayne State University School of Medicine, Detroit, Michigan
| | - Paul B. Manis
- Department of Otolaryngology/Head and Neck Surgery; The University of North Carolina at Chapel Hill; Chapel Hill North Carolina
- Department of Cell and Molecular Physiology and Curriculum in Neurobiology, The University of North Carolina at Chapel Hill; Chapel Hill North Carolina
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Chen L, Yung KKL, Chan YS, Yung WH. 5-HT excites globus pallidus neurons by multiple receptor mechanisms. Neuroscience 2007; 151:439-51. [PMID: 18082329 DOI: 10.1016/j.neuroscience.2007.11.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2007] [Revised: 10/31/2007] [Accepted: 11/30/2007] [Indexed: 11/26/2022]
Abstract
Anatomical and neurochemical studies indicated that the globus pallidus receives serotonergic innervation from raphe nuclei but the membrane effects of 5-HT on globus pallidus neurons are not entirely clear. We address this question by applying whole-cell patch-clamp recordings on globus pallidus neurons in immature rat brain slices. Under current-clamp recording, 5-HT depolarized globus pallidus neurons and increased their firing rate, an action blocked by both 5-HT(4) and 5-HT(7) receptor antagonists and attributable to an increase in cation conductance(s). Further experiments indicated that 5-HT enhanced the hyperpolarization-activated inward conductance which is blocked by 5-HT(7) receptor antagonist. To determine if 5-HT exerts any presynaptic effects on GABAergic and glutamatergic inputs, the actions of 5-HT on synaptic currents were studied. At 10 microM, 5-HT increased the frequency of spontaneous inhibitory postsynaptic currents (sIPSCs) but had no effect on both the frequency and amplitude of miniature inhibitory postsynaptic currents (mIPSCs). However, 5-HT at a higher concentration (50 microM) decreased the frequency but not the amplitude of the mIPSCs, indicating an inhibition of GABA release from the presynaptic terminals. This effect was sensitive to 5-HT(1B) receptor antagonist. In addition to the presynaptic effects on GABAergic neurotransmission, 5-HT at 50 microM had no consistent effects on glutamatergic neurotransmission, significantly increased the frequency of miniature excitatory postsynaptic currents (mEPSCs) in 4 of 11 neurons and decreased the frequency of mEPSCs in 3 of 11 neurons. In conclusion, we found that 5-HT could modulate the excitability of globus pallidus neurons by both pre- and post-synaptic mechanisms. In view of the extensive innervation by globus pallidus neurons on other basal ganglia nuclei, this action of 5-HT originated from the raphe may have a profound effect on the operation of the entire basal ganglia network.
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Affiliation(s)
- L Chen
- Department of Physiology, The Chinese University of Hong Kong, Shatin, Hong Kong, China
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Brunelli SA, Hofer MA. Selective breeding for infant rat separation-induced ultrasonic vocalizations: developmental precursors of passive and active coping styles. Behav Brain Res 2007; 182:193-207. [PMID: 17543397 PMCID: PMC2759113 DOI: 10.1016/j.bbr.2007.04.014] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2007] [Revised: 04/17/2007] [Accepted: 04/20/2007] [Indexed: 11/26/2022]
Abstract
Human depression and anxiety disorders show inherited biases across generations, as do antisocial disorders characterized by aggression. Each condition is preceded in children by behavioral inhibition or aggressive behavior, respectively, and both are characterized by separation anxiety disorders. In affected families, adults and children exhibit different forms of altered autonomic nervous system regulation and hypothalamic-pituitary-adrenal activity in response to stress. Because it is difficult to determine mechanisms accounting for these associations, animal studies are useful for studying the fundamental relationships between biological and behavioral traits. Pharmacologic and behavioral studies suggest that infant rat ultrasonic vocalizations (USV) are a measure of an early anxiety-like state related to separation anxiety. However, it was not known whether or not early ultrasound emissions in infant rats are markers for genetic risk for anxiety states later in life. To address these questions, we selectively bred two lines of rats based on high and low rates of USV to isolation at postnatal (P) 10 days of age. To our knowledge, ours is the only laboratory that has ever selectively bred on the basis of an infantile trait related to anxiety. The High and Low USV lines show two distinct sets of patterns of behavior, physiology and neurochemistry from infancy through adulthood. As adults High line rats demonstrate "anxious"/"depressed" phenotypes in behavior and autonomic nervous system (ANS) regulation to standard laboratory tests. In Lows, on the other hand, behavior and autonomic regulation are consistent with an "aggressive" phenotype. The High and Low USV lines are the first genetic animal models implicating long-term associations of contrasting "coping styles" with early attachment responses. They thus present a potentially powerful model for examining gene-environment interactions in the development of life-long affective regulation.
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Affiliation(s)
- Susan A Brunelli
- Developmental Neuroscience, New York State Psychiatric Institute, New York, NY 10032,
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