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Bobula B, Bąk J, Kania A, Siwiec M, Kiełbiński M, Tokarski K, Pałucha-Poniewiera A, Hess G. Maternal fluoxetine impairs synaptic transmission and plasticity in the medial prefrontal cortex and alters the structure and function of dorsal raphe nucleus neurons in offspring mice. Pharmacol Biochem Behav 2024; 244:173849. [PMID: 39142357 DOI: 10.1016/j.pbb.2024.173849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2024] [Revised: 08/08/2024] [Accepted: 08/09/2024] [Indexed: 08/16/2024]
Abstract
Selective serotonin (5-HT) reuptake inhibitors (SSRIs) are commonly prescribed to women during pregnancy and breastfeeding despite posing a risk of adverse cognitive outcomes and affective disorders for the child. The consequences of SSRI-induced excess of 5-HT during development for the brain neuromodulatory 5-HT system remain largely unexplored. In this study, an SSRI - fluoxetine (FLX) - was administered to C57BL/6 J mouse dams during pregnancy and lactation to assess its effects on the offspring. We found that maternal FLX decreased field potentials, impaired long-term potentiation, facilitated long-term depression and tended to increase the density of 5-HTergic fibers in the medial prefrontal cortex (mPFC) of female but not male adolescent offspring. These effects were accompanied by deteriorated performance in the temporal order memory task and reduced sucrose preference with no change in marble burying behavior in FLX-exposed female offspring. We also found that maternal FLX reduced the axodendritic tree complexity of 5-HT dorsal raphe nucleus (DRN) neurons in female but not male offspring, with no changes in the excitability of DRN neurons of either sex. While no effects of maternal FLX on inhibitory postsynaptic currents (sIPSCs) in DRN neurons were found, we observed a significant influence of FLX exposure on kinetics of spontaneous excitatory postsynaptic currents (sEPSCs) in DRN neurons. Finally, we report that no changes in field potentials and synaptic plasticity were evident in the mPFC of the offspring after maternal exposure during pregnancy and lactation to a new antidepressant, vortioxetine. These findings show that in contrast to the mPFC, long-term consequences of maternal FLX exposure on the structure and function of DRN 5-HT neurons are mild and suggest a sex-dependent, distinct sensitivity of cortical and brainstem neurons to FLX exposure in early life. Vortioxetine appears to exert fewer side effects with regards to the mPFC when compared with FLX.
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Affiliation(s)
- Bartosz Bobula
- Department of Physiology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Krakow, Poland.
| | - Joanna Bąk
- Department of Physiology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Krakow, Poland
| | - Agnieszka Kania
- Department of Physiology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Krakow, Poland.
| | - Marcin Siwiec
- Department of Physiology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Krakow, Poland.
| | - Michał Kiełbiński
- Department of Physiology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Krakow, Poland.
| | - Krzysztof Tokarski
- Department of Physiology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Krakow, Poland.
| | - Agnieszka Pałucha-Poniewiera
- Department of Neurobiology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Krakow, Poland.
| | - Grzegorz Hess
- Department of Physiology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Krakow, Poland.
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2
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Galindo-Charles L, Reyes-Legorreta C, Garduño J, Galarraga E, Tapia D, Hernández-López S. The activation of D2-like dopamine receptors increases NMDA currents in the dorsal raphe serotonergic neurons. Neurosci Lett 2024; 839:137933. [PMID: 39128818 DOI: 10.1016/j.neulet.2024.137933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2024] [Revised: 07/29/2024] [Accepted: 08/08/2024] [Indexed: 08/13/2024]
Abstract
The dorsal raphe nucleus (DRN) receives dopaminergic inputs from the ventral tegmental area (VTA). Also, the DRN contains a small population of cells that express dopamine (DRNDA neurons). However, the physiological role of dopamine (DA) in the DRN and its interaction with serotonergic (5-HT) neurons is poorly understood. Several works have reported moderate levels of D1, D2, and D3 DA receptors in the DRN. Furthermore, it was found that the activation of D2 receptors increased the firing of putative 5-HT neurons. Other studies have reported that D1 and D2 dopamine receptors can interact with glutamate NMDA receptors, modulating the excitability of different cell types. In the present work, we used immunocytochemical techniques to determine the kind of DA receptors in the DRN. Additionally, we performed electrophysiological experiments in brainstem slices to study the effect of DA agonists on NMDA-elicited currents recorded from identified 5-HT DRN neurons. We found that D2 and D3 but not D1 receptors are present in this nucleus. Also, we demonstrated that the activation of D2-like receptors increases NMDA-elicited currents in 5-HT neurons through a mechanism involving phospholipase C (PLC) and protein kinase C (PKC) enzymes. Possible physiological implications related to the sleep-wake cycle are discussed.
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Affiliation(s)
- L Galindo-Charles
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), Ciudad de México 04510, Mexico
| | - C Reyes-Legorreta
- Laboratorio de Neuroprotección, Instituto Nacional de Rehabilitación-LGII, Ciudad de México 14389, Mexico
| | - J Garduño
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), Ciudad de México 04510, Mexico
| | - E Galarraga
- División de Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México (UNAM), Ciudad de México 04510, Mexico
| | - D Tapia
- División de Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México (UNAM), Ciudad de México 04510, Mexico
| | - S Hernández-López
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), Ciudad de México 04510, Mexico.
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3
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Pascovich C, Serantes D, Rodriguez A, Mateos D, González J, Gallo D, Rivas M, Devera A, Lagos P, Rubido N, Torterolo P. Dorsal and median raphe neuronal firing dynamics characterized by nonlinear measures. PLoS Comput Biol 2024; 20:e1012111. [PMID: 38805554 PMCID: PMC11161118 DOI: 10.1371/journal.pcbi.1012111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 06/07/2024] [Accepted: 04/25/2024] [Indexed: 05/30/2024] Open
Abstract
The dorsal (DRN) and median (MRN) raphe are important nuclei involved in similar functions, including mood and sleep, but playing distinct roles. These nuclei have a different composition of neuronal types and set of neuronal connections, which among other factors, determine their neuronal dynamics. Most works characterize the neuronal dynamics using classic measures, such as using the average spiking frequency (FR), the coefficient of variation (CV), and action potential duration (APD). In the current study, to refine the characterization of neuronal firing profiles, we examined the neurons within the raphe nuclei. Through the utilization of nonlinear measures, our objective was to discern the redundancy and complementarity of these measures, particularly in comparison with classic methods. To do this, we analyzed the neuronal basal firing profile in both nuclei of urethane-anesthetized rats using the Shannon entropy (Bins Entropy) of the inter-spike intervals, permutation entropy of ordinal patterns (OP Entropy), and Permutation Lempel-Ziv Complexity (PLZC). Firstly, we found that classic (i.e., FR, CV, and APD) and nonlinear measures fail to distinguish between the dynamics of DRN and MRN neurons, except for the OP Entropy. We also found strong relationships between measures, including the CV with FR, CV with Bins entropy, and FR with PLZC, which imply redundant information. However, APD and OP Entropy have either a weak or no relationship with the rest of the measures tested, suggesting that they provide complementary information to the characterization of the neuronal firing profiles. Secondly, we studied how these measures are affected by the oscillatory properties of the firing patterns, including rhythmicity, bursting patterns, and clock-like behavior. We found that all measures are sensitive to rhythmicity, except for the OP Entropy. Overall, our work highlights OP Entropy as a powerful and useful quantity for the characterization of neuronal discharge patterns.
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Affiliation(s)
- Claudia Pascovich
- Laboratory of Sleep Neurobiology, Department of Physiology, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
- Consciousness and Cognition Laboratory, Department of Psychology, King’s College, University of Cambridge, Cambridge, United Kingdom
| | - Diego Serantes
- Laboratory of Sleep Neurobiology, Department of Physiology, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Alejo Rodriguez
- Laboratory of Sleep Neurobiology, Department of Physiology, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Diego Mateos
- Achucarro Basque Center for Neuroscience, Leioa (Bizkaia), Spain
- Instituto de Matemática Aplicada del Litoral (IMAL-CONICET-UNL), Santa Fé, Argentina
- Universidad Autónoma de Entre Ríos (UADER), Oro Verde, Entre Ríos, Argentina
| | - Joaquín González
- Laboratory of Sleep Neurobiology, Department of Physiology, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Diego Gallo
- Laboratory of Sleep Neurobiology, Department of Physiology, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Mayda Rivas
- Laboratory of Sleep Neurobiology, Department of Physiology, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Andrea Devera
- Laboratory of Sleep Neurobiology, Department of Physiology, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Patricia Lagos
- Laboratory of Neuropeptide Transmission, Department of Physiology, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Nicolás Rubido
- Institute for Complex Systems and Mathematical Biology, King’s College, University of Aberdeen, Aberdeen, United Kingdom
| | - Pablo Torterolo
- Laboratory of Sleep Neurobiology, Department of Physiology, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
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Zhang Y, Huang CC, Zhao J, Liu Y, Xia M, Wang X, Wei D, Chen Y, Liu B, Zheng Y, Wu Y, Chen T, Cheng Y, Xu X, Gong Q, Si T, Qiu S, Cheng J, Tang Y, Wang F, Qiu J, Xie P, Li L, He Y, Lin CP, Zac Lo CY. Resting-state functional connectivity of the raphe nuclei in major depressive Disorder: A Multi-site study. Neuroimage Clin 2023; 37:103359. [PMID: 36878150 PMCID: PMC9999207 DOI: 10.1016/j.nicl.2023.103359] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 11/06/2022] [Accepted: 02/20/2023] [Indexed: 03/06/2023]
Abstract
Accumulating evidence showed that major depressive disorder (MDD) is characterized by a dysfunction of serotonin neurotransmission. Raphe nuclei are the sources of most serotonergic neurons that project throughout the brain. Incorporating measurements of activity within the raphe nuclei into the analysis of connectivity characteristics may contribute to understanding how neurotransmitter synthesized centers are involved in thepathogenesisof MDD. Here, we analyzed the resting-state functional magnetic resonance imaging (RS-fMRI) dataset from 1,148 MDD patients and 1,079 healthy individuals recruited across nine centers. A seed-based analysis with the dorsal raphe and median raphe nuclei was performed to explore the functional connectivity (FC) alterations. Compared to controls, for dorsal raphe, the significantly decreased FC linking with the right precuneus and median cingulate cortex were found; for median raphe, the increased FC linking with right superior cerebellum (lobules V/VI) was found in MDD patients. In further exploratory analyzes, MDD-related connectivity alterations in dorsal and median raphe nuclei in different clinical factors remained highly similar to the main findings, indicating these abnormal connectivities are a disease-related alteration. Our study highlights a functional dysconnection pattern of raphe nuclei in MDD with multi-site big data. These findings help improve our understanding of the pathophysiology of depression and provide evidence of the theoretical foundation for the development of novel pharmacotherapies.
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Affiliation(s)
- Yajuan Zhang
- Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai 200433, China; School of Biomedical Engineering, ShanghaiTech University, Shanghai, China
| | - Chu-Chung Huang
- Shanghai Key Laboratory of Brain Functional Genomics (Ministry of Education), Affiliated Mental Health Center (ECNU), School of Psychology and Cognitive Science, East China Normal University, Shanghai, China; Shanghai Changning Mental Health Center, Shanghai, China.
| | - Jiajia Zhao
- Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai 200433, China
| | - Yuchen Liu
- Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai 200433, China
| | - Mingrui Xia
- State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China; Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China; IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China
| | - Xiaoqin Wang
- Key Laboratory of Cognition and Personality (SWU), Ministry of Education, Chongqing, China; Department of Psychology, Southwest University, Chongqing, China
| | - Dongtao Wei
- Key Laboratory of Cognition and Personality (SWU), Ministry of Education, Chongqing, China; Department of Psychology, Southwest University, Chongqing, China
| | - Yuan Chen
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Bangshan Liu
- Department of Psychiatry, and National Clinical Research Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China; Mental Health Institute of Central South University, China National Technology Institute on Mental Disorders, Hunan Key Laboratory of Psychiatry and Mental Health, Hunan Medical Center for Mental Health, Changsha, Hunan, China
| | - Yanting Zheng
- Department of Radiology, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yankun Wu
- Peking University Sixth Hospital, Peking University Institute of Mental Health, NHC Key Laboratory of Mental Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Peking University, Beijing, China
| | - Taolin Chen
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital, Sichuan University, Chengdu, China; Research Unit of Psychoradiology, Chinese Academy of Medical Sciences, Chengdu, Sichuan, China
| | - Yuqi Cheng
- Department of Psychiatry, First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Xiufeng Xu
- Department of Psychiatry, First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Qiyong Gong
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital, Sichuan University, Chengdu, China; Research Unit of Psychoradiology, Chinese Academy of Medical Sciences, Chengdu, Sichuan, China
| | - Tianmei Si
- Peking University Sixth Hospital, Peking University Institute of Mental Health, NHC Key Laboratory of Mental Health (Peking University), National Clinical Research Center for Mental Disorders (Peking University Sixth Hospital), Peking University, Beijing, China
| | - Shijun Qiu
- Department of Radiology, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Jingliang Cheng
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Yanqing Tang
- Department of Psychiatry, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Fei Wang
- Department of Psychiatry, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Jiang Qiu
- Key Laboratory of Cognition and Personality (SWU), Ministry of Education, Chongqing, China; Department of Psychology, Southwest University, Chongqing, China
| | - Peng Xie
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China; NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China; Chongqing Key Laboratory of Neurobiology, Chongqing, China
| | - Lingjiang Li
- Department of Psychiatry, and National Clinical Research Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China; Mental Health Institute of Central South University, China National Technology Institute on Mental Disorders, Hunan Key Laboratory of Psychiatry and Mental Health, Hunan Medical Center for Mental Health, Changsha, Hunan, China
| | - Yong He
- State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China; Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China; IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China; Institute for Brain Research, Beijing, China
| | - Ching-Po Lin
- Institute of Neuroscience, National Yang Ming Chiao Tung University, Taipei, 11221, Taiwan
| | | | - Chun-Yi Zac Lo
- Department of Biomedical Engineering, Chung Yuan Christian University, Taoyuan, 32023, Taiwan.
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Bohne P, Volkmann A, Schwarz MK, Mark MD. Deletion of the P/Q-Type Calcium Channel from Serotonergic Neurons Drives Male Aggression in Mice. J Neurosci 2022; 42:6637-6653. [PMID: 35853721 PMCID: PMC9410759 DOI: 10.1523/jneurosci.0204-22.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 06/27/2022] [Accepted: 06/30/2022] [Indexed: 11/25/2022] Open
Abstract
Aggressive behavior is one of the most conserved social interactions in nature and serves as a crucial evolutionary trait. Serotonin (5-HT) plays a key role in the regulation of our emotions, such as anxiety and aggression, but which molecules and mechanisms in the serotonergic system are involved in violent behavior are still unknown. In this study, we show that deletion of the P/Q-type calcium channel selectively from serotonergic neurons in the dorsal raphe nuclei (DRN) augments aggressive behavior in male mice, while anxiety is not affected. These mice demonstrated increased induction of the immediate early gene c-fos and in vivo serotonergic firing activity in the DRN. The ventrolateral part of the ventromedial hypothalamus is also a prominent region of the brain mediating aggression. We confirmed a monosynaptic projection from the DRN to the ventrolateral part of the ventromedial hypothalamus, and silencing these projections with an inhibitory designer receptor exclusively activated by a designer drug effectively reduced aggressive behavior. Overall, our findings show that deletion of the P/Q-type calcium channel from DRN neurons is sufficient to induce male aggression in mice and regulating its activity may serve as a therapeutic approach to treat violent behavior.SIGNIFICANCE STATEMENT In this study, we show that P/Q-type calcium channel is mediating aggression in serotonergic neurons from the dorsal raphe nucleus via monosynaptic projections to the ventrolateral part of the ventromedial hypothalamus. More importantly, silencing these projections reduced aggressive behavior in mice and may serve as a therapeutic approach for treating aggression in humans.
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Affiliation(s)
- Pauline Bohne
- Behavioral Neuroscience, Ruhr-University Bochum, Bochum, D-44780, Germany
| | - Achim Volkmann
- Behavioral Neuroscience, Ruhr-University Bochum, Bochum, D-44780, Germany
| | - Martin K Schwarz
- Institute of Experimental Epileptology and Cognition Research, University of Bonn Medical School, Bonn, D-53127, Germany
| | - Melanie D Mark
- Behavioral Neuroscience, Ruhr-University Bochum, Bochum, D-44780, Germany
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Social interactions increase activation of vasopressin-responsive neurons in the dorsal raphe. Neuroscience 2022; 495:25-46. [DOI: 10.1016/j.neuroscience.2022.05.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 05/18/2022] [Accepted: 05/24/2022] [Indexed: 11/19/2022]
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Neural serotonergic circuits for controlling long-term voluntary alcohol consumption in mice. Mol Psychiatry 2022; 27:4599-4610. [PMID: 36195637 PMCID: PMC9531213 DOI: 10.1038/s41380-022-01789-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 09/05/2022] [Accepted: 09/09/2022] [Indexed: 12/14/2022]
Abstract
Alcohol-use-disorders are chronic relapsing illnesses, often co-morbid with anxiety. We have previously shown using the "drinking-in-the-dark" model in mice that the stimulation of the serotonin receptor 1A (5-HT1A) reduces ethanol binge-drinking behaviour and withdrawal-induced anxiety. The 5-HT1A receptor is located either on Raphe neurons as autoreceptors, or on target neurons as heteroreceptors. By combining a pharmacological approach with biased agonists targeting the 5-HT1A auto- or heteroreceptor and a chemogenetic approach (DREADDs), here we identified that ethanol-binge drinking behaviour is dependent on 5-HT1A autoreceptors and 5-HT neuronal function, with a transition from DRN-dependent regulation of short-term (6 weeks) ethanol intake, to MRN-dependent regulation after longer ethanol exposure (12 weeks). We further identified a serotonergic microcircuit (5-HTMRN→DG) originating from the MRN and projecting to the dentate gyrus (DG) of the hippocampus, that is specifically affected by, and modulates long-term ethanol consumption. The present study indicates that targeting Raphe nuclei 5-HT1A autoreceptors with agonists might represent an innovative pharmacotherapeutic strategy to combat alcohol abuse.
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Hashimoto K, Yamawaki Y, Yamaoka K, Yoshida T, Okada K, Tan W, Yamasaki M, Matsumoto-Makidono Y, Kubo R, Nakayama H, Kataoka T, Kanematsu T, Watanabe M, Okamoto Y, Morinobu S, Aizawa H, Yamawaki S. Spike firing attenuation of serotonin neurons in learned helplessness rats is reversed by ketamine. Brain Commun 2021; 3:fcab285. [PMID: 34939032 PMCID: PMC8688795 DOI: 10.1093/braincomms/fcab285] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 10/04/2021] [Accepted: 10/25/2021] [Indexed: 11/14/2022] Open
Abstract
Animals suffering from uncontrollable stress sometimes show low effort to escape stress (learned helplessness). Changes in serotonin (5-hydroxytryptamine) signalling are thought to underlie this behaviour. Although the release of 5-hydroxytryptamine is triggered by the action potential firing of dorsal raphe nuclei 5-hydroxytryptamine neurons, the electrophysiological changes induced by uncontrollable stress are largely unclear. Herein, we examined electrophysiological differences among 5-hydroxytryptamine neurons in naïve rats, learned helplessness rats and rats resistant to inescapable stress (non-learned helplessness). Five-week-old male Sprague Dawley rats were exposed to inescapable foot shocks. After an avoidance test session, rats were classified as learned helplessness or non-learned helplessness. Activity-dependent 5-hydroxytryptamine release induced by the administration of high-potassium solution was slower in free-moving learned helplessness rats. Subthreshold electrophysiological properties of 5-hydroxytryptamine neurons were identical among the three rat groups, but the depolarization-induced spike firing was significantly attenuated in learned helplessness rats. To clarify the underlying mechanisms, potassium (K+) channels regulating the spike firing were initially examined using naïve rats. K+ channels sensitive to 500 μM tetraethylammonium caused rapid repolarization of the action potential and the small conductance calcium-activated K+ channels produced afterhyperpolarization. Additionally, dendrotoxin-I, a blocker of Kv1.1 (encoded by Kcna1), Kv1.2 (encoded by Kcna2) and Kv1.6 (encoded by Kcna6) voltage-dependent K+ channels, weakly enhanced the spike firing frequency during depolarizing current injections without changes in individual spike waveforms in naïve rats. We found that dendrotoxin-I significantly enhanced the spike firing of 5-hydroxytryptamine neurons in learned helplessness rats. Consequently, the difference in spike firing among the three rat groups was abolished in the presence of dendrotoxin-I. These results suggest that the upregulation of dendrotoxin-I-sensitive Kv1 channels underlies the firing attenuation of 5-hydroxytryptamine neurons in learned helplessness rats. We also found that the antidepressant ketamine facilitated the spike firing of 5-hydroxytryptamine neurons and abolished the firing difference between learned helplessness and non-learned helplessness by suppressing dendrotoxin-I-sensitive Kv1 channels. The dendrotoxin-I-sensitive Kv1 channel may be a potential target for developing drugs to control activity of 5-hydroxytryptamine neurons.
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Affiliation(s)
- Kouichi Hashimoto
- Department of Neurophysiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Yosuke Yamawaki
- Department of Cellular and Molecular Pharmacology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Kenji Yamaoka
- Department of Neurophysiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Takayuki Yoshida
- Department of Neurophysiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Kana Okada
- Department of Neurophysiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Wanqin Tan
- Department of Neurobiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Miwako Yamasaki
- Department of Anatomy, Faculty of Medicine, Hokkaido University, Sapporo 060-8638, Japan
| | - Yoshiko Matsumoto-Makidono
- Department of Neurophysiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Reika Kubo
- Department of Neurophysiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Hisako Nakayama
- Department of Neurophysiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Tsutomu Kataoka
- Department of Psychiatry and Neurosciences, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Takashi Kanematsu
- Department of Cellular and Molecular Pharmacology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Masahiko Watanabe
- Department of Anatomy, Faculty of Medicine, Hokkaido University, Sapporo 060-8638, Japan
| | - Yasumasa Okamoto
- Department of Psychiatry and Neurosciences, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Shigeru Morinobu
- Department of Psychiatry and Neurosciences, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Hidenori Aizawa
- Department of Neurobiology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
| | - Shigeto Yamawaki
- Department of Psychiatry and Neurosciences, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan
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9
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McDevitt RA, Marino RAM, Tejeda HA, Bonci A. Serotonergic inhibition of responding for conditioned but not primary reinforcers. Pharmacol Biochem Behav 2021; 205:173186. [PMID: 33836219 DOI: 10.1016/j.pbb.2021.173186] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 02/19/2021] [Accepted: 03/29/2021] [Indexed: 10/21/2022]
Abstract
Serotonin is widely implicated as a modulator of brain reward function. However, laboratory studies have not yielded a consensus on which specific reward-related processes are influenced by serotonin and in what manner. Here we explored the role of serotonin in cue-reward learning in mice. In a first series of experiments, we found that acute administration of the serotonin reuptake inhibitors citalopram, fluoxetine, or duloxetine all reduced lever pressing reinforced on an FR1 schedule with presentation of a cue that had been previously paired with delivery of food. However, citalopram had no effect on responding that was reinforced with both cue and food on an FR1 schedule. Furthermore, citalopram did not affect nose poke responses that produced no auditory, visual, or proprioceptive cues but were reinforced with food pellets on a progressive ratio schedule. We next performed region-specific knock out of tryptophan hydroxylase-2 (Tph2), the rate-limiting enzyme in serotonin synthesis. Viral delivery of Cre recombinase was targeted to dorsal or median raphe nuclei (DRN, MRN), the major sources of ascending serotonergic projections. MRN but not DRN knockouts were impaired in development of cue-elicited approach during Pavlovian conditioning; both groups were subsequently hyper-responsive when lever pressing for cue presentation. The inhibitory effect of citalopram was attenuated in DRN but not MRN knockouts. Our findings are in agreement with prior studies showing serotonin to suppress responding for conditioned reinforcers. Furthermore, these results suggest an inhibitory role of MRN serotonin neurons in the initial attribution of motivational properties to a reward-predictive cue, but not in its subsequent maintenance. In contrast, the DRN appears to promote the reduction of motivational value attached to a cue when it is presented repeatedly in the absence of primary reward.
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Affiliation(s)
- Ross A McDevitt
- Synaptic Plasticity Section, National Institute on Drug Abuse, Baltimore, MD, United States of America; Comparative Medicine Section, National Institute on Aging, Baltimore, MD, United States of America.
| | - Rosa Anna M Marino
- Synaptic Plasticity Section, National Institute on Drug Abuse, Baltimore, MD, United States of America; Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Hugo A Tejeda
- Synaptic Plasticity Section, National Institute on Drug Abuse, Baltimore, MD, United States of America; Neuromodulation and Synaptic Integration Unit, National Institute on Mental Health, Bethesda, MD, United States of America
| | - Antonello Bonci
- Global Institutes on Addictions, Miami, FL, United States of America
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10
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Soga T, Nakajima S, Parhar IS. Expression of Repressor Element 1 Silencing Transcription Factor (REST) in Serotonin Neurons in the Adult Male Nile Tilapia ( Oreochromis niloticus). Front Neuroanat 2021; 14:599540. [PMID: 33776659 PMCID: PMC7990894 DOI: 10.3389/fnana.2020.599540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 12/21/2020] [Indexed: 11/15/2022] Open
Abstract
Repressor element-1 silencing transcription factor (REST) is highly expressed in the dorsal raphe where serotonin (5-hydroxytryptamine, 5-HT) neurons are located. REST works as a transcription factor for the 5-HT receptor and tryptophan hydroxylase two-gene expression. We hypothesized that REST is co-expressed in 5-HT neurons, which, if demonstrated, would be useful to understand the mechanism of 5-HT dysfunction-related disorders such as negative emotions and depression. Therefore, the present study was designed to examine the expression of the REST gene in the brain (forebrain, midbrain, and hindbrain) of adult male Nile tilapia (Oreochromis niloticus) using rt-PCR. Besides, using immunocytochemistry, co-localization of the REST gene was examined in 5-HT neurons and with neuronal-/glial-cell markers. We found a high expression of the REST gene in the midbrain region of the dorsal raphe, an area of 5-HT neurons. Double-label immunocytochemistry showed neuron-specific expression of REST co-localized in 5-HT neurons in the dorsal and ventral parts of the periventricular pretectal nucleus, paraventricular organ, and dorsal and medial raphe nucleus. Since midbrain 5-HT neurons express REST, we speculate that REST may control 5-HT neuronal activity related to negative emotions, including depression.
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Affiliation(s)
- Tomoko Soga
- Brain Research Institute Monash Sunway (BRIMS), Jeffery Cheah School of Medicine and Health Sciences, Monash University Malaysia, Selangor, Malaysia
| | - Shingo Nakajima
- Brain Research Institute Monash Sunway (BRIMS), Jeffery Cheah School of Medicine and Health Sciences, Monash University Malaysia, Selangor, Malaysia
| | - Ishwar S Parhar
- Brain Research Institute Monash Sunway (BRIMS), Jeffery Cheah School of Medicine and Health Sciences, Monash University Malaysia, Selangor, Malaysia
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11
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Jansch C, Ziegler GC, Forero A, Gredy S, Wäldchen S, Vitale MR, Svirin E, Zöller JEM, Waider J, Günther K, Edenhofer F, Sauer M, Wischmeyer E, Lesch KP. Serotonin-specific neurons differentiated from human iPSCs form distinct subtypes with synaptic protein assembly. J Neural Transm (Vienna) 2021; 128:225-241. [PMID: 33560471 PMCID: PMC7914246 DOI: 10.1007/s00702-021-02303-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 01/10/2021] [Indexed: 02/06/2023]
Abstract
Human induced pluripotent stem cells (hiPSCs) have revolutionized the generation of experimental disease models, but the development of protocols for the differentiation of functionally active neuronal subtypes with defined specification is still in its infancy. While dysfunction of the brain serotonin (5-HT) system has been implicated in the etiology of various neuropsychiatric disorders, investigation of functional human 5-HT specific neurons in vitro has been restricted by technical limitations. We describe an efficient generation of functionally active neurons from hiPSCs displaying 5-HT specification by modification of a previously reported protocol. Furthermore, 5-HT specific neurons were characterized using high-end fluorescence imaging including super-resolution microscopy in combination with electrophysiological techniques. Differentiated hiPSCs synthesize 5-HT, express specific markers, such as tryptophan hydroxylase 2 and 5-HT transporter, and exhibit an electrophysiological signature characteristic of serotonergic neurons, with spontaneous rhythmic activities, broad action potentials and large afterhyperpolarization potentials. 5-HT specific neurons form synapses reflected by the expression of pre- and postsynaptic proteins, such as Bassoon and Homer. The distribution pattern of Bassoon, a marker of the active zone along the soma and extensions of neurons, indicates functionality via volume transmission. Among the high percentage of 5-HT specific neurons (~ 42%), a subpopulation of CDH13 + cells presumably designates dorsal raphe neurons. hiPSC-derived 5-HT specific neuronal cell cultures reflect the heterogeneous nature of dorsal and median raphe nuclei and may facilitate examining the association of serotonergic neuron subpopulations with neuropsychiatric disorders.
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Affiliation(s)
- Charline Jansch
- Division of Molecular Psychiatry, Center of Mental Health, University of Würzburg, Margarete-Höppel-Platz 1, 97080, Würzburg, Germany
| | - Georg C Ziegler
- Division of Molecular Psychiatry, Center of Mental Health, University of Würzburg, Margarete-Höppel-Platz 1, 97080, Würzburg, Germany.
- Department of Psychiatry, Psychosomatics and Psychotherapy, Center of Mental Health, University of Würzburg, Würzburg, Germany.
| | - Andrea Forero
- Division of Molecular Psychiatry, Center of Mental Health, University of Würzburg, Margarete-Höppel-Platz 1, 97080, Würzburg, Germany
| | - Sina Gredy
- Institute of Physiology, Molecular Electrophysiology, University of Würzburg, Würzburg, Germany
- Laboratory of Psychiatric Neurobiology, Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia
| | - Sina Wäldchen
- Department of Biotechnology and Biophysics, Biocenter, University of Würzburg, Würzburg, Germany
| | - Maria Rosaria Vitale
- Division of Molecular Psychiatry, Center of Mental Health, University of Würzburg, Margarete-Höppel-Platz 1, 97080, Würzburg, Germany
- Laboratory of Psychiatric Neurobiology, Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia
| | - Evgeniy Svirin
- Division of Molecular Psychiatry, Center of Mental Health, University of Würzburg, Margarete-Höppel-Platz 1, 97080, Würzburg, Germany
- Laboratory of Psychiatric Neurobiology, Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia
| | - Johanna E M Zöller
- Division of Molecular Psychiatry, Center of Mental Health, University of Würzburg, Margarete-Höppel-Platz 1, 97080, Würzburg, Germany
- Department of Translational Neuroscience, School for Mental Health and Neuroscience (MHeNS), Maastricht University, Maastricht, The Netherlands
| | - Jonas Waider
- Division of Molecular Psychiatry, Center of Mental Health, University of Würzburg, Margarete-Höppel-Platz 1, 97080, Würzburg, Germany
| | - Katharina Günther
- Department of Genomics, Stem Cell Biology and Regenerative Medicine, Institute of Molecular Biology and CMBI, Leopold-Franzens-University Innsbruck, Innsbruck, Austria
- Institute of Molecular Regenerative Medicine, SCI-TReCS, Paracelsus Medical University, Salzburg, Austria
| | - Frank Edenhofer
- Department of Genomics, Stem Cell Biology and Regenerative Medicine, Institute of Molecular Biology and CMBI, Leopold-Franzens-University Innsbruck, Innsbruck, Austria
| | - Markus Sauer
- Department of Biotechnology and Biophysics, Biocenter, University of Würzburg, Würzburg, Germany
| | - Erhard Wischmeyer
- Division of Molecular Psychiatry, Center of Mental Health, University of Würzburg, Margarete-Höppel-Platz 1, 97080, Würzburg, Germany
- Institute of Physiology, Molecular Electrophysiology, University of Würzburg, Würzburg, Germany
| | - Klaus-Peter Lesch
- Division of Molecular Psychiatry, Center of Mental Health, University of Würzburg, Margarete-Höppel-Platz 1, 97080, Würzburg, Germany.
- Laboratory of Psychiatric Neurobiology, Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, Russia.
- Department of Translational Neuroscience, School for Mental Health and Neuroscience (MHeNS), Maastricht University, Maastricht, The Netherlands.
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Charvériat M, Guiard BP. Serotonergic neurons in the treatment of mood disorders: The dialogue with astrocytes. PROGRESS IN BRAIN RESEARCH 2021; 259:197-228. [PMID: 33541677 DOI: 10.1016/bs.pbr.2021.01.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Astrocytes were traditionally regarded as cells important to neuronal activity, providing both metabolic and structural supports. Recent evidence suggests that they may also play a crucial role in the control of higher brain functions. In keeping with this hypothesis, it is now well accepted that astrocytes contribute to stress but also react to antidepressant drugs as they express serotonergic transporters and receptors. However, the downstream mechanisms leading to the fine-tuned regulation of mood are still unknown. This chapter pays attention to the role of astrocytes in the regulation of emotional behavior and related serotonergic neurotransmission. In particular, it gives a current state of the clinical and preclinical evidence showing that astrocytes respond to environmental conditions and antidepressant drugs through the release of gliotransmitters and neurotrophic factors which in turn, influence serotonergic tone in discrete brain areas. This state-of-the-art review aims at demonstrating the remarkable potential for novel therapeutic antidepressant strategies targeting these glial cells.
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Affiliation(s)
| | - Bruno P Guiard
- Centre de Recherches sur la Cognition Animale, Centre de Biologie Intégrative, Université de Toulouse, CNRS, Toulouse, France.
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13
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Yaman B, Bal R. Pindolol potentiates the antidepressant effect of venlafaxine by inhibiting 5-HT1A receptor in DRN neurons of mice. Int J Neurosci 2020; 132:23-30. [DOI: 10.1080/00207454.2020.1797723] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Burak Yaman
- Medicine Faculty, Department of Physiology, Gaziantep University, Gaziantep, Turkey
| | - Ramazan Bal
- Medicine Faculty, Department of Physiology, Gaziantep University, Gaziantep, Turkey
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14
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Serotonin hyperpolarizes the dorsal raphe nucleus neurons of mice by activating G protein–coupled inward rectifier potassium channels. Neuroreport 2020; 31:928-935. [DOI: 10.1097/wnr.0000000000001501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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15
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Li X, Sun X, Sun J, Zu Y, Zhao S, Sun X, Li L, Zhang X, Wang W, Liang Y, Wang W, Liang X, Sun C, Guan X, Tang M. Depressive-like state sensitizes 5-HT 1A and 5-HT 1B auto-receptors in the dorsal raphe nucleus sub-system. Behav Brain Res 2020; 389:112618. [PMID: 32360167 DOI: 10.1016/j.bbr.2020.112618] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 03/16/2020] [Accepted: 03/17/2020] [Indexed: 12/14/2022]
Abstract
Dorsal raphe (DR) and median raphe (MR) 5-HT neurons are two distinct sub-systems known to be regulated by 5-HT1A and 5-HT1B auto-receptors. Whether the auto-receptors in each sub-system are functionally altered in depressive-like state remains unknown. The present study is aimed to study a specific circuit (DR-ventral hippocampus and MR-dorsal hippocampus) within each sub-system to investigate changes in receptor sensitivity in the pathogenesis of depression. A mouse model of depression was developed through the social defeat paradigm, and was then treated with fluoxetine (FLX). 5-HT1A auto-receptor in the neuronal cell body (DR or MR) and 5-HT1B auto-receptor in the axonal terminal (ventral or dorsal hippocampus) were directly targeted by local perfusion of antagonists (5-HT1A: WAY100635; 5-HT1B: GR127935) through reverse microdialysis. Time courses of dialysate 5-HT measured at the axonal terminal were subsequently determined for each circuit. At baseline, 5-HT1A and 5-HT1B antagonists dose-dependently increased dialysate 5-HT, with sub-circuit specificity. In the depressive-like state, greater increases in dialysate 5-HT were observed only in the DR-ventral hippocampus circuit following local delivery of both antagonists, which were then fully restored following the FLX treatment. In contrast, no changes were observed in the MR-dorsal hippocampus circuit. Our results demonstrate differential changes in sensitivities of 5-HT1A and 5-HT1B auto-receptors in the DR-ventral hippocampus and MR-dorsal hippocampus circuits. 5-HT1A and 5-HT1B auto-receptors in the DR-ventral hippocampus circuit are sensitized in the depressive-like state. Taken together, these results suggest that the DR sub-system maybe the neural substrate mediating depressive phenotypes.
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Affiliation(s)
- Xiang Li
- Department of Pharmacy, The Fourth Affiliated Hospital of China Medical University, Shenyang, 110032, China
| | - Xianan Sun
- Department of Clinical Pharmacology, School of Pharmacy, China Medical University, Shenyang, 110122, China
| | - Jing Sun
- Department of Outpatient, Rocket Force University of Engineering Clinic Affiliated to 986 Hospital of Air Force, Xi'an, 710043, China
| | - Yi Zu
- Department of Academic Quality Assurance, China Medical University, Shenyang, 110122, China
| | - Shulei Zhao
- Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, Maryland, 20993, USA
| | - Xiao Sun
- Department of Internal Medicine, Shenyang Women's and Children's Hospital, Shenyang, 110011, China
| | - Lu Li
- Department of Clinical Pharmacology, School of Pharmacy, China Medical University, Shenyang, 110122, China
| | - Xinjing Zhang
- Department of Clinical Pharmacology, School of Pharmacy, China Medical University, Shenyang, 110122, China
| | - Wei Wang
- Department of Clinical Pharmacology, School of Pharmacy, China Medical University, Shenyang, 110122, China
| | - Yuezhu Liang
- Department of Clinical Pharmacology, School of Pharmacy, China Medical University, Shenyang, 110122, China
| | - Wenyao Wang
- Department of Clinical Pharmacology, School of Pharmacy, China Medical University, Shenyang, 110122, China
| | - Xuankai Liang
- Department of Clinical Pharmacology, School of Pharmacy, China Medical University, Shenyang, 110122, China
| | - Chi Sun
- Department of Academic Quality Assurance, China Medical University, Shenyang, 110122, China
| | - Xue Guan
- Department of Academic Quality Assurance, China Medical University, Shenyang, 110122, China
| | - Man Tang
- Department of Clinical Pharmacology, School of Pharmacy, China Medical University, Shenyang, 110122, China.
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16
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Pascovich C, Lagos P, Urbanavicius J, Devera A, Rivas M, Costa A, López Hill X, Falconi A, Scorza C, Torterolo P. Melanin-concentrating hormone (MCH) in the median raphe nucleus: Fibers, receptors and cellular effects. Peptides 2020; 126:170249. [PMID: 31911169 DOI: 10.1016/j.peptides.2019.170249] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 11/11/2019] [Accepted: 12/26/2019] [Indexed: 11/20/2022]
Abstract
Serotonergic neurons of the median raphe nucleus (MnR) and hypothalamic melanin-concentrating hormone (MCH)-containing neurons, have been involved in the control of REM sleep and mood. In the present study, we examined in rats and cats the anatomical relationship between MCH-containing fibers and MnR neurons, as well as the presence of MCHergic receptors in these neurons. In addition, by means of in vivo unit recording in urethane anesthetized rats, we determined the effects of MCH in MnR neuronal firing. Our results showed that MCH-containing fibers were present in the central and paracentral regions of the MnR. MCHergic fibers were in close apposition to serotonergic and non-serotonergic neurons. By means of an indirect approach, we also analyzed the presence of MCHergic receptors within the MnR. Accordingly, we microinjected MCH conjugated with the fluorophore rhodamine (R-MCH) into the lateral ventricle. R-MCH was internalized into serotonergic and non-serotonergic MnR neurons; some of these neurons were GABAergic. Furthermore, we determined that intracerebroventricular administration of MCH induced a significant decrease in the firing rate of 53 % of MnR neurons, while the juxtacellular administration of MCH reduced the frequency of discharge in 67 % of these neurons. Finally, the juxtacellular administration of the MCH-receptor antagonist ATC-0175 produced an increase in the firing rate in 78 % of MnR neurons. Hence, MCH produces a strong regulation of MnR neuronal activity. We hypothesize that MCHergic modulation of the MnR neuronal activity may be involved in the promotion of REM sleep and in the pathophysiology of depressive disorders.
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Affiliation(s)
- Claudia Pascovich
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Patricia Lagos
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Jessika Urbanavicius
- Departamento de Neurofarmacología Experimental, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
| | - Andrea Devera
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Mayda Rivas
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Alicia Costa
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Ximena López Hill
- Departamento de Neurofarmacología Experimental, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
| | - Atilio Falconi
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Cecilia Scorza
- Departamento de Neurofarmacología Experimental, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
| | - Pablo Torterolo
- Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay.
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17
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Abstract
Neurons that synthesize and release 5-hydroxytryptamine (5-HT; serotonin) express a core set of genes that establish and maintain this neurotransmitter phenotype and distinguish these neurons from other brain cells. Beyond a shared 5-HTergic phenotype, these neurons display divergent cellular properties in relation to anatomy, morphology, hodology, electrophysiology and gene expression, including differential expression of molecules supporting co-transmission of additional neurotransmitters. This diversity suggests that functionally heterogeneous subtypes of 5-HT neurons exist, but linking subsets of these neurons to particular functions has been technically challenging. We discuss recent data from molecular genetic, genomic and functional methods that, when coupled with classical findings, yield a reframing of the 5-HT neuronal system as a conglomeration of diverse subsystems with potential to inspire novel, more targeted therapies for clinically distinct 5-HT-related disorders.
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18
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Abela AR, Browne CJ, Sargin D, Prevot TD, Ji XD, Li Z, Lambe EK, Fletcher PJ. Median raphe serotonin neurons promote anxiety-like behavior via inputs to the dorsal hippocampus. Neuropharmacology 2020; 168:107985. [PMID: 32035145 DOI: 10.1016/j.neuropharm.2020.107985] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 01/29/2020] [Accepted: 01/31/2020] [Indexed: 11/16/2022]
Abstract
Anxiety disorders may be mediated in part by disruptions in serotonin (5-hydroxytryptamine, 5-HT) system function. Behavioral measures of approach-avoidance conflict suggest that serotonin neurons within the median raphe nucleus (MRN) promote an anxiogenic state, and some evidence indicates this may be mediated by serotonergic signaling within the dorsal hippocampus. Here, we test this hypothesis using an optogenetic approach to examine the contribution of MRN 5-HT neurons and 5-HT innervation of the dorsal hippocampus (dHC) to anxiety-like behaviours in female mice. Mice expressing the excitatory opsin ChR2 were generated by crossing the ePet-cre serotonergic cre-driver line with the conditional Ai32 ChR2 reporter line, resulting in selective expression of ChR2 in 5-HT neurons. Electrophysiological recordings confirmed that this approach enabled reliable optogenetic stimulation of MRN 5-HT neurons, and this stimulation produced downstream 5-HT release in the dHC as measured by in vivo microdialysis. Optogenetic stimulation of the MRN elicited behavioral responses indicative of an anxiogenic effect in three behavioural tests: novelty-suppressed feeding, marble burying and exploration on the elevated-plus maze. These effects were shown to be behaviourally-specific. Stimulation of 5-HT terminals in the dHC recapitulated the anxiety-like behaviour in the novelty-suppressed feeding and marble burying tests. These results show that activation of 5-HT efferents from the MRN rapidly induces expression of anxiety-like behaviour, in part via projections to the dHC. These findings reveal an important neural circuit implicated in the expression of anxiety in female mice.
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Affiliation(s)
- Andrew R Abela
- Preclinical Research and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St., Toronto, ON, M5T 1R8, Canada; Dept. of Psychiatry, University of Toronto, Toronto, ON, Canada.
| | - Caleb J Browne
- Preclinical Research and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St., Toronto, ON, M5T 1R8, Canada; Dept. of Psychology, University of Toronto, Toronto, ON, Canada; Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, New York, NY, 10029, USA
| | - Derya Sargin
- Dept. of Physiology, University of Toronto, Toronto, ON, Canada; Dept. of Psychology, University of Calgary, Calgary, AB, Canada
| | - Thomas D Prevot
- Preclinical Research and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St., Toronto, ON, M5T 1R8, Canada
| | - Xiao Dong Ji
- Preclinical Research and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St., Toronto, ON, M5T 1R8, Canada
| | - Zhaoxia Li
- Preclinical Research and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St., Toronto, ON, M5T 1R8, Canada
| | - Evelyn K Lambe
- Dept. of Psychiatry, University of Toronto, Toronto, ON, Canada; Dept. of Physiology, University of Toronto, Toronto, ON, Canada; Dept. of Obstetrics and Gynaecology, University of Toronto, ON, Canada
| | - Paul J Fletcher
- Preclinical Research and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St., Toronto, ON, M5T 1R8, Canada; Dept. of Psychiatry, University of Toronto, Toronto, ON, Canada; Dept. of Psychology, University of Toronto, Toronto, ON, Canada
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19
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Mark MD, Wollenweber P, Gesk A, Kösters K, Batzke K, Janoschka C, Maejima T, Han J, Deneris ES, Herlitze S. RGS2 drives male aggression in mice via the serotonergic system. Commun Biol 2019; 2:373. [PMID: 31633064 PMCID: PMC6789038 DOI: 10.1038/s42003-019-0622-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 09/19/2019] [Indexed: 12/23/2022] Open
Abstract
Aggressive behavior in our modern, civilized society is often counterproductive and destructive. Identifying specific proteins involved in the disease can serve as therapeutic targets for treating aggression. Here, we found that overexpression of RGS2 in explicitly serotonergic neurons augments male aggression in control mice and rescues male aggression in Rgs2-/- mice, while anxiety is not affected. The aggressive behavior is directly correlated to the immediate early gene c-fos induction in the dorsal raphe nuclei and ventrolateral part of the ventromedial nucleus hypothalamus, to an increase in spontaneous firing in serotonergic neurons and to a reduction in the modulatory action of Gi/o and Gq/11 coupled 5HT and adrenergic receptors in serotonergic neurons of Rgs2-expressing mice. Collectively, these findings specifically identify that RGS2 expression in serotonergic neurons is sufficient to drive male aggression in mice and as a potential therapeutic target for treating aggression.
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Affiliation(s)
- Melanie D. Mark
- Department of General Zoology and Neurobiology, Ruhr-University Bochum, 44780 Bochum, Germany
| | - Patric Wollenweber
- Department of General Zoology and Neurobiology, Ruhr-University Bochum, 44780 Bochum, Germany
| | - Annika Gesk
- Department of General Zoology and Neurobiology, Ruhr-University Bochum, 44780 Bochum, Germany
| | - Katja Kösters
- Department of General Zoology and Neurobiology, Ruhr-University Bochum, 44780 Bochum, Germany
| | - Katharina Batzke
- Department of General Zoology and Neurobiology, Ruhr-University Bochum, 44780 Bochum, Germany
| | - Claudia Janoschka
- Department of General Zoology and Neurobiology, Ruhr-University Bochum, 44780 Bochum, Germany
| | - Takashi Maejima
- Department of Integrative Neurophysiology, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, 920-8640 Japan
| | - Jing Han
- Institute for Applied Cancer Science, University of Texas, MD Anderson Cancer Center, Houston, TX 77030 USA
| | - Evan S. Deneris
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH USA
| | - Stefan Herlitze
- Department of General Zoology and Neurobiology, Ruhr-University Bochum, 44780 Bochum, Germany
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20
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Vahid-Ansari F, Zhang M, Zahrai A, Albert PR. Overcoming Resistance to Selective Serotonin Reuptake Inhibitors: Targeting Serotonin, Serotonin-1A Receptors and Adult Neuroplasticity. Front Neurosci 2019; 13:404. [PMID: 31114473 PMCID: PMC6502905 DOI: 10.3389/fnins.2019.00404] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 04/09/2019] [Indexed: 12/14/2022] Open
Abstract
Major depressive disorder (MDD) is the most prevalent mental illness contributing to global disease burden. Selective serotonin (5-HT) reuptake inhibitors (SSRIs) are the first-line treatment for MDD, but are only fully effective in 30% of patients and require weeks before improvement may be seen. About 30% of SSRI-resistant patients may respond to augmentation or switching to another antidepressant, often selected by trial and error. Hence a better understanding of the causes of SSRI resistance is needed to provide models for optimizing treatment. Since SSRIs enhance 5-HT, in this review we discuss new findings on the circuitry, development and function of the 5-HT system in modulating behavior, and on how 5-HT neuronal activity is regulated. We focus on the 5-HT1A autoreceptor, which controls 5-HT activity, and the 5-HT1A heteroreceptor that mediates 5-HT actions. A series of mice models now implicate increased levels of 5-HT1A autoreceptors in SSRI resistance, and the requirement of hippocampal 5-HT1A heteroreceptor for neurogenic and behavioral response to SSRIs. We also present clinical data that show promise for identifying biomarkers of 5-HT activity, 5-HT1A regulation and regional changes in brain activity in MDD patients that may provide biomarkers for tailored interventions to overcome or bypass resistance to SSRI treatment. We identify a series of potential strategies including inhibiting 5-HT auto-inhibition, stimulating 5-HT1A heteroreceptors, other monoamine systems, or cortical stimulation to overcome SSRI resistance.
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Affiliation(s)
| | | | | | - Paul R. Albert
- Brain and Mind Research Institute, Ottawa Hospital Research Institute (Neuroscience), University of Ottawa, Ottawa, ON, Canada
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21
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Vilela-Costa HH, Spiacci A, Bissolli IG, Zangrossi H. A Shift in the Activation of Serotonergic and Non-serotonergic Neurons in the Dorsal Raphe Lateral Wings Subnucleus Underlies the Panicolytic-Like Effect of Fluoxetine in Rats. Mol Neurobiol 2019; 56:6487-6500. [DOI: 10.1007/s12035-019-1536-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 02/22/2019] [Indexed: 01/04/2023]
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22
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Quentin E, Belmer A, Maroteaux L. Somato-Dendritic Regulation of Raphe Serotonin Neurons; A Key to Antidepressant Action. Front Neurosci 2018; 12:982. [PMID: 30618598 PMCID: PMC6307465 DOI: 10.3389/fnins.2018.00982] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 12/07/2018] [Indexed: 11/22/2022] Open
Abstract
Several lines of evidence implicate serotonin (5-hydroxytryptamine, 5-HT)in regulating personality traits and mood control. Serotonergic neurons are classically thought to be tonic regular-firing, “clock-like” neurons. Neurotransmission by serotonin is tightly regulated by the serotonin transporter (SERT) and by autoreceptors (serotonin receptors expressed by serotonin neurons) through negative feedback inhibition at the cell bodies and dendrites (5-HT1A receptors) of the dorsal raphe nuclei or at the axon terminals (5-HT1B receptors). In dorsal raphe neurons, the release of serotonin from vesicles in the soma, dendrites, and/or axonal varicosities is independent of classical synapses and can be induced by neuron depolarization, by the stimulation of L-type calcium channels, by activation of glutamatergic receptors, and/or by activation of 5-HT2 receptors. The resulting serotonin release displays a slow kinetic and a large diffusion. This process called volume transmission may ultimately affect the rate of discharge of serotonergic neurons, and their tonic activity. The therapeutic effects induced by serotonin-selective reuptake inhibitor (SSRI) antidepressants are initially triggered by blocking SERT but rely on consequences of chronic exposure, i.e., a selective desensitization of somatodendritic 5-HT1A autoreceptors. Agonist stimulation of 5-HT2B receptors mimicked behavioral and neurogenic SSRI actions, and increased extracellular serotonin in dorsal raphe. By contrast, a lack of effects of SSRIs was observed in the absence of 5-HT2B receptors (knockout-KO), even restricted to serotonergic neurons (Htr2b5-HTKO mice). The absence of 5-HT2B receptors in serotonergic neurons is associated with a higher 5-HT1A-autoreceptor reactivity and thus a lower firing activity of these neurons. In agreement, mice with overexpression of 5-HT1A autoreceptor show decreased neuronal activity and increased depression-like behavior that is resistant to SSRI treatment. We propose thus that the serotonergic tone results from the opposite control exerted by somatodendritic (Gi-coupled) 5-HT1A and (Gq-coupled) 5-HT2B receptors on dorsal raphe neurons. Therefore, 5-HT2B receptors may contribute to SSRI therapeutic effects by their positive regulation of adult raphe serotonergic neurons. Deciphering the molecular mechanism controlling extrasynaptic release of serotonin, and how autoreceptors interact in regulating the tonic activity of serotonergic neurons, is critical to fully understand the therapeutic effect of SSRIs.
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Affiliation(s)
- Emily Quentin
- INSERM UMR-S 839, Institut du Fer à Moulin, Paris, France.,Sorbonne Universités, UPMC University Paris 6, Paris, France.,Institut du Fer à Moulin, Paris, France
| | - Arnauld Belmer
- INSERM UMR-S 839, Institut du Fer à Moulin, Paris, France.,Sorbonne Universités, UPMC University Paris 6, Paris, France.,Institut du Fer à Moulin, Paris, France
| | - Luc Maroteaux
- INSERM UMR-S 839, Institut du Fer à Moulin, Paris, France.,Sorbonne Universités, UPMC University Paris 6, Paris, France.,Institut du Fer à Moulin, Paris, France
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23
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Cham KL, Soga T, Parhar IS. Expression of RING Finger Protein 38 in Serotonergic Neurons in the Brain of Nile Tilapia, Oreochromis niloticus. Front Neuroanat 2018; 12:109. [PMID: 30574074 PMCID: PMC6292424 DOI: 10.3389/fnana.2018.00109] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 11/21/2018] [Indexed: 11/13/2022] Open
Abstract
Serotonin (5-hydroxytryptamine, 5-HT) is one of the major neurotransmitters, modulating diverse behaviours and physiological functions. Really interesting new gene (RING) finger protein 38 (RNF38) is an E3 ubiquitin ligase whose function remains unclear. A recent study has shown a possible regulatory relationship between RNF38 and the 5-HT system. Therefore, to gain insight into the role of RNF38 in the central 5-HT system, we identified the neuroanatomical location of 5-HT positive cells and investigated the relationship between RNF38 and the 5-HT system in the brain of the Nile tilapia, Oreochromis niloticus. Immunocytochemistry revealed three neuronal populations of 5-HT in the brain of tilapia; the paraventricular organ (PVO), the dorsal and ventral periventricular pretectal nuclei (PPd and PPv), and, the superior and inferior raphe (SR and IR). The 5-HT neuronal number was highest in the raphe (90.4 in SR, 284.6 in IR), followed by the pretectal area (22.3 in PPd, 209.8 in PPv). Double-label immunocytochemistry showed that the majority of 5-HT neurons express RNF38 nuclear proteins (66.5% in PPd; 77.9% in PPv; 35.7% in SR; 49.1% in IR). These findings suggest that RNF38 could be involved in E3 ubiquitination in the central 5-HT system.
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Affiliation(s)
- Kai Lin Cham
- Brain Research Institute, School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Malaysia
| | - Tomoko Soga
- Brain Research Institute, School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Malaysia
| | - Ishwar S Parhar
- Brain Research Institute, School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Malaysia
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24
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Nissen NI, Anderson KR, Wang H, Lee HS, Garrison C, Eichelberger SA, Ackerman K, Im W, Miwa JM. Augmenting the antinociceptive effects of nicotinic acetylcholine receptor activity through lynx1 modulation. PLoS One 2018; 13:e0199643. [PMID: 29969495 PMCID: PMC6029753 DOI: 10.1371/journal.pone.0199643] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 06/11/2018] [Indexed: 12/13/2022] Open
Abstract
Neuronal nicotinic acetylcholine receptors (nAChRs) of the cholinergic system have been linked to antinociception, and therefore could be an alternative target for pain alleviation. nAChR activity has been shown to be regulated by the nicotinic modulator, lynx1, which forms stable complexes with nAChRs and has a negative allosteric action on their function. The objective in this study was to investigate the contribution of lynx1 to nicotine-mediated antinociception. Lynx1 contribution was investigated by mRNA expression analysis and electrophysiological responses to nicotine in the dorsal raphe nucleus (DRN), a part of the pain signaling pathway. In vivo antinociception was investigated in a test of nociception, the hot-plate analgesia assay with behavioral pharmacology. Lynx1/α4β2 nAChR interactions were investigated using molecular dynamics computational modeling. Nicotine evoked responses in serotonergic and GABAergic neurons in the DRN are augmented in slices lacking lynx1 (lynx1KO). The antinociceptive effect of nicotine and epibatidine is enhanced in lynx1KO mice and blocked by mecamylamine and DHβE. Computer simulations predict preferential binding affinity of lynx1 to the α:α interface that exists in the stoichiometry of the low sensitivity (α4)3(β2)2 nAChRs. Taken together, these data point to a role of lynx1 in mediating pain signaling in the DRN through preferential affinity to the low sensitivity α4β2 nAChRs. This study suggests that lynx1 is a possible alternative avenue for nociceptive modulation outside of opioid-based strategies.
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Affiliation(s)
- Neel I. Nissen
- Department of Biological Science, Lehigh University, Bethlehem, PA, United States of America
- Department of Health Science and Technology, Aalborg University, Aalborg, Denmark
| | - Kristin R. Anderson
- Department of Biological Science, Lehigh University, Bethlehem, PA, United States of America
| | - Huaixing Wang
- Department of Biological Science, Lehigh University, Bethlehem, PA, United States of America
| | - Hui Sun Lee
- Department of Biological Science, Lehigh University, Bethlehem, PA, United States of America
| | - Carly Garrison
- Department of Biological Science, Lehigh University, Bethlehem, PA, United States of America
| | | | - Kasarah Ackerman
- Department of Biological Science, Lehigh University, Bethlehem, PA, United States of America
| | - Wonpil Im
- Department of Biological Science, Lehigh University, Bethlehem, PA, United States of America
| | - Julie M. Miwa
- Department of Biological Science, Lehigh University, Bethlehem, PA, United States of America
- * E-mail:
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25
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Llamosas N, Ugedo L, Torrecilla M. Inactivation of GIRK channels weakens the pre- and postsynaptic inhibitory activity in dorsal raphe neurons. Physiol Rep 2018; 5:5/3/e13141. [PMID: 28196855 PMCID: PMC5309581 DOI: 10.14814/phy2.13141] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 12/26/2016] [Accepted: 01/06/2017] [Indexed: 01/17/2023] Open
Abstract
The serotonergic tone of the dorsal raphe (DR) is regulated by 5-HT1A receptors, which negatively control serotonergic activity via the activation of G protein-coupled inwardly rectifying K+ (GIRK) channels. In addition, DR activity is modulated by local GABAergic transmission, which is believed to play a key role in the development of mood-related disorders. Here, we sought to characterize the role of GIRK2 subunit-containing channels on the basal electrophysiological properties of DR neurons and to investigate whether the presynaptic and postsynaptic activities of 5-HT1A, GABAB, and GABAA receptors are affected by Girk2 gene deletion. Whole-cell patch-clamp recordings in brain slices from GIRK2 knockout mice revealed that the GIRK2 subunit contributes to maintenance of the resting membrane potential and to the membrane input resistance of DR neurons. 5-HT1A and GABAB receptor-mediated postsynaptic currents were almost absent in the mutant mice. Spontaneous and evoked GABAA receptor-mediated transmissions were markedly reduced in GIRK2 KO mice, as the frequency and amplitude of spontaneous IPSCs were reduced, the paired-pulse ratio was increased and GABA-induced whole-cell currents were decreased. Similarly, the pharmacological blockade of GIRK channels with tertiapin-Q prevented the 5-HT1A and GABAB receptor-mediated postsynaptic currents and increased the paired-pulse ratio. Finally, deletion of the Girk2 gene also limited the presynaptic inhibition of GABA release exerted by 5-HT1A and GABAB receptors. These results indicate that the properties and inhibitory activity of DR neurons are highly regulated by GIRK2 subunit-containing channels, introducing GIRK channels as potential candidates for studying the pathophysiology and treatment of affective disorders.
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Affiliation(s)
- Nerea Llamosas
- Department of Pharmacology, Faculty of Medicine and Nursing, University of the Basque Country UPV/EHU, Leioa, Spain
| | - Luisa Ugedo
- Department of Pharmacology, Faculty of Medicine and Nursing, University of the Basque Country UPV/EHU, Leioa, Spain
| | - Maria Torrecilla
- Department of Pharmacology, Faculty of Medicine and Nursing, University of the Basque Country UPV/EHU, Leioa, Spain
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26
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Belmer A, Quentin E, Diaz SL, Guiard BP, Fernandez SP, Doly S, Banas SM, Pitychoutis PM, Moutkine I, Muzerelle A, Tchenio A, Roumier A, Mameli M, Maroteaux L. Positive regulation of raphe serotonin neurons by serotonin 2B receptors. Neuropsychopharmacology 2018; 43:1623-1632. [PMID: 29453444 PMCID: PMC5983540 DOI: 10.1038/s41386-018-0013-0] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 01/10/2018] [Accepted: 01/17/2018] [Indexed: 01/03/2023]
Abstract
Serotonin is a neurotransmitter involved in many psychiatric diseases. In humans, a lack of 5-HT2B receptors is associated with serotonin-dependent phenotypes, including impulsivity and suicidality. A lack of 5-HT2B receptors in mice eliminates the effects of molecules that directly target serotonergic neurons including amphetamine derivative serotonin releasers, and selective serotonin reuptake inhibitor antidepressants. In this work, we tested the hypothesis that 5-HT2B receptors directly and positively regulate raphe serotonin neuron activity. By ex vivo electrophysiological recordings, we report that stimulation by the 5-HT2B receptor agonist, BW723C86, increased the firing frequency of serotonin Pet1-positive neurons. Viral overexpression of 5-HT2B receptors in these neurons increased their excitability. Furthermore, in vivo 5-HT2B-receptor stimulation by BW723C86 counteracted 5-HT1A autoreceptor-dependent reduction in firing rate and hypothermic response in wild-type mice. By a conditional genetic ablation that eliminates 5-HT2B receptor expression specifically and exclusively from Pet1-positive serotonin neurons (Htr2b 5-HTKO mice), we demonstrated that behavioral and sensitizing effects of MDMA (3,4-methylenedioxy-methamphetamine), as well as acute behavioral and chronic neurogenic effects of the antidepressant fluoxetine, require 5-HT2B receptor expression in serotonergic neurons. In Htr2b 5-HTKO mice, dorsal raphe serotonin neurons displayed a lower firing frequency compared to control Htr2b lox/lox mice as assessed by in vivo extracellular recordings and a stronger hypothermic effect of 5-HT1A-autoreceptor stimulation was observed. The increase in head-twitch response to DOI (2,5-dimethoxy-4-iodoamphetamine) further confirmed the lower serotonergic tone resulting from the absence of 5-HT2B receptors in serotonin neurons. Together, these observations indicate that the 5-HT2B receptor acts as a direct positive modulator of serotonin Pet1-positive neurons in an opposite way as the known 5-HT1A-negative autoreceptor.
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Affiliation(s)
- Arnauld Belmer
- 0000000121866389grid.7429.8INSERM UMR-S 839, 75005 Paris, France ,0000 0001 2308 1657grid.462844.8Sorbonne Universités, UPMC Univ Paris 6, 75005 Paris, France ,0000 0004 0520 8345grid.462192.aInstitut du Fer à Moulin, 75005 Paris, France ,0000000089150953grid.1024.7Translational Research Institute, Queensland University of Technology, Brisbane, QLD 4059 Australia
| | - Emily Quentin
- 0000000121866389grid.7429.8INSERM UMR-S 839, 75005 Paris, France ,0000 0001 2308 1657grid.462844.8Sorbonne Universités, UPMC Univ Paris 6, 75005 Paris, France ,0000 0004 0520 8345grid.462192.aInstitut du Fer à Moulin, 75005 Paris, France
| | - Silvina L. Diaz
- 0000000121866389grid.7429.8INSERM UMR-S 839, 75005 Paris, France ,0000 0001 2308 1657grid.462844.8Sorbonne Universités, UPMC Univ Paris 6, 75005 Paris, France ,0000 0004 0520 8345grid.462192.aInstitut du Fer à Moulin, 75005 Paris, France ,grid.441705.3Instituto de Biología Celular y Neurociencia, Fac. de Cs. Exactas, Químicas y Naturales, Universidad de Morón, UBA-CONICET – Paraguay 2155, 3° piso, C1121ABG Buenos Aires, Argentina
| | - Bruno P. Guiard
- Research Center on Animal Cognition, Center for Integrative Biology, 31062 Toulouse, France ,0000 0001 0723 035Xgrid.15781.3aUniversité Paul Sabatier, 31062 Toulouse, France ,UMR5169 CNRS, 31062 Toulouse, France
| | - Sebastian P. Fernandez
- 0000000121866389grid.7429.8INSERM UMR-S 839, 75005 Paris, France ,0000 0001 2308 1657grid.462844.8Sorbonne Universités, UPMC Univ Paris 6, 75005 Paris, France ,0000 0004 0520 8345grid.462192.aInstitut du Fer à Moulin, 75005 Paris, France ,0000 0004 0638 0649grid.429194.3IPMC – CNRS UMR7275 660 Route des Lucioles Sophia-Antipolis, 06560 Valbonne, France
| | - Stéphane Doly
- 0000000121866389grid.7429.8INSERM UMR-S 839, 75005 Paris, France ,0000 0001 2308 1657grid.462844.8Sorbonne Universités, UPMC Univ Paris 6, 75005 Paris, France ,0000 0004 0520 8345grid.462192.aInstitut du Fer à Moulin, 75005 Paris, France ,grid.503334.2Université Clermont Auvergne, INSERM, NEURO-DOL, 63000 Clermont-Ferrand, France
| | - Sophie M. Banas
- 0000000121866389grid.7429.8INSERM UMR-S 839, 75005 Paris, France ,0000 0001 2308 1657grid.462844.8Sorbonne Universités, UPMC Univ Paris 6, 75005 Paris, France ,0000 0004 0520 8345grid.462192.aInstitut du Fer à Moulin, 75005 Paris, France
| | - Pothitos M. Pitychoutis
- 0000000121866389grid.7429.8INSERM UMR-S 839, 75005 Paris, France ,0000 0001 2308 1657grid.462844.8Sorbonne Universités, UPMC Univ Paris 6, 75005 Paris, France ,0000 0004 0520 8345grid.462192.aInstitut du Fer à Moulin, 75005 Paris, France ,0000 0001 2175 167Xgrid.266231.2Department of Biology and Center for Tissue Regeneration and Engineering at Dayton (TREND), University of Dayton, Dayton, OH USA
| | - Imane Moutkine
- 0000000121866389grid.7429.8INSERM UMR-S 839, 75005 Paris, France ,0000 0001 2308 1657grid.462844.8Sorbonne Universités, UPMC Univ Paris 6, 75005 Paris, France ,0000 0004 0520 8345grid.462192.aInstitut du Fer à Moulin, 75005 Paris, France
| | - Aude Muzerelle
- 0000000121866389grid.7429.8INSERM UMR-S 839, 75005 Paris, France ,0000 0001 2308 1657grid.462844.8Sorbonne Universités, UPMC Univ Paris 6, 75005 Paris, France ,0000 0004 0520 8345grid.462192.aInstitut du Fer à Moulin, 75005 Paris, France
| | - Anna Tchenio
- 0000000121866389grid.7429.8INSERM UMR-S 839, 75005 Paris, France ,0000 0001 2308 1657grid.462844.8Sorbonne Universités, UPMC Univ Paris 6, 75005 Paris, France ,0000 0004 0520 8345grid.462192.aInstitut du Fer à Moulin, 75005 Paris, France ,0000 0001 2165 4204grid.9851.5Dept. Fundamental Neurosciences (DNF) The University of Lausanne, Lausanne, Switzerland
| | - Anne Roumier
- 0000000121866389grid.7429.8INSERM UMR-S 839, 75005 Paris, France ,0000 0001 2308 1657grid.462844.8Sorbonne Universités, UPMC Univ Paris 6, 75005 Paris, France ,0000 0004 0520 8345grid.462192.aInstitut du Fer à Moulin, 75005 Paris, France
| | - Manuel Mameli
- 0000000121866389grid.7429.8INSERM UMR-S 839, 75005 Paris, France ,0000 0001 2308 1657grid.462844.8Sorbonne Universités, UPMC Univ Paris 6, 75005 Paris, France ,0000 0004 0520 8345grid.462192.aInstitut du Fer à Moulin, 75005 Paris, France ,0000 0001 2165 4204grid.9851.5Dept. Fundamental Neurosciences (DNF) The University of Lausanne, Lausanne, Switzerland
| | - Luc Maroteaux
- INSERM UMR-S 839, 75005, Paris, France. .,Sorbonne Universités, UPMC Univ Paris 6, 75005, Paris, France. .,Institut du Fer à Moulin, 75005, Paris, France.
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Abstract
Investigation of how anesthetics produce hypnosis requires knowledge of their effects at the molecular, neuronal, circuit, and whole-brain network level. Anesthetic photolabels have long been used to explore how anesthetics bind and affect known protein targets, but they could potentially assist in investigation of anesthetic effects at higher organizational levels of the central nervous system. Here, we advocate the use and provide detailed methods for the application of anesthetic photolabels in slice electrophysiology and in intact animals as a means of investigating anesthetic effects on distinct circuits and brain centers.
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28
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Wong-Lin K, Wang DH, Moustafa AA, Cohen JY, Nakamura K. Toward a multiscale modeling framework for understanding serotonergic function. J Psychopharmacol 2017; 31:1121-1136. [PMID: 28417684 PMCID: PMC5606304 DOI: 10.1177/0269881117699612] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Despite its importance in regulating emotion and mental wellbeing, the complex structure and function of the serotonergic system present formidable challenges toward understanding its mechanisms. In this paper, we review studies investigating the interactions between serotonergic and related brain systems and their behavior at multiple scales, with a focus on biologically-based computational modeling. We first discuss serotonergic intracellular signaling and neuronal excitability, followed by neuronal circuit and systems levels. At each level of organization, we will discuss the experimental work accompanied by related computational modeling work. We then suggest that a multiscale modeling approach that integrates the various levels of neurobiological organization could potentially transform the way we understand the complex functions associated with serotonin.
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Affiliation(s)
- KongFatt Wong-Lin
- Intelligent Systems Research Centre, School of Computing and Intelligent Systems, University of Ulster, Magee Campus, Derry~Londonderry, UK
| | - Da-Hui Wang
- School of Systems Science, and National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China
| | - Ahmed A Moustafa
- School of Social Sciences and Psychology, and Marcs Institute for Brain and Behaviour, University of Western Sydney, Sydney, Australia
| | - Jeremiah Y Cohen
- Solomon H. Snyder Department of Neuroscience, Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Kae Nakamura
- Department of Physiology, Kansai Medical University, Hirakata, Osaka, Japan
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29
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Oliveira MAP, Balling R, Smidt MP, Fleming RMT. Embryonic development of selectively vulnerable neurons in Parkinson's disease. NPJ Parkinsons Dis 2017; 3:21. [PMID: 28685157 PMCID: PMC5484687 DOI: 10.1038/s41531-017-0022-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 05/24/2017] [Accepted: 06/01/2017] [Indexed: 02/07/2023] Open
Abstract
A specific set of brainstem nuclei are susceptible to degeneration in Parkinson's disease. We hypothesise that neuronal vulnerability reflects shared phenotypic characteristics that confer selective vulnerability to degeneration. Neuronal phenotypic specification is mainly the cumulative result of a transcriptional regulatory program that is active during the development. By manual curation of the developmental biology literature, we comprehensively reconstructed an anatomically resolved cellular developmental lineage for the adult neurons in five brainstem regions that are selectively vulnerable to degeneration in prodromal or early Parkinson's disease. We synthesised the literature on transcription factors that are required to be active, or required to be inactive, in the development of each of these five brainstem regions, and at least two differentially vulnerable nuclei within each region. Certain transcription factors, e.g., Ascl1 and Lmx1b, seem to be required for specification of many brainstem regions that are susceptible to degeneration in early Parkinson's disease. Some transcription factors can even distinguish between differentially vulnerable nuclei within the same brain region, e.g., Pitx3 is required for specification of the substantia nigra pars compacta, but not the ventral tegmental area. We do not suggest that Parkinson's disease is a developmental disorder. In contrast, we consider identification of shared developmental trajectories as part of a broader effort to identify the molecular mechanisms that underlie the phenotypic features that are shared by selectively vulnerable neurons. Systematic in vivo assessment of fate determining transcription factors should be completed for all neuronal populations vulnerable to degeneration in early Parkinson's disease.
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Affiliation(s)
- Miguel A. P. Oliveira
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, 6 Avenue du Swing, Belvaux, L-4362 Luxembourg
| | - Rudi Balling
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, 6 Avenue du Swing, Belvaux, L-4362 Luxembourg
| | - Marten P. Smidt
- Department of Molecular Neuroscience, Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, Sciencepark 904, 1098 XH Amsterdam, The Netherlands
| | - Ronan M. T. Fleming
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, 6 Avenue du Swing, Belvaux, L-4362 Luxembourg
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30
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Andrade TGCSD, Silva JVDS, Batistela MF, Frei F, Sant'Ana AB. Interaction between estradiol and 5-HT 1A receptors in the median raphe nucleus on acquisition of aversive information and association to the context in ovariectomized rats. Neurobiol Stress 2017. [PMID: 28626786 PMCID: PMC5470534 DOI: 10.1016/j.ynstr.2017.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The median raphe nucleus (MRN) is related to stress resistance and defensive responses, a crucial source of serotonergic neurons that project to prosencephalic structures related to stress and anxiety. Estrogen receptors were identified in this mesencephalic structure. It is possible that the estrogen action is related to serotonin effect on somatodendritic 5-HT1A receptors, inhibiting the function of serotonergic neurons and thus preventing of the stress effect and inducing anxiolysis. So, in order to evaluate these aspects, female Wistar rats were ovariectomized and 21 days later were given a direct microinjection of estradiol benzoate (EB) (1200 ng) into the MRN, preceded by microinjections of saline or WAY100.635 (100 ng), a 5-HT1A receptor antagonist. Immediately after the two microinjections, the ovariectomized rats were conditioned with an aversive event (foot shock) session in a Skinner box. Twenty-four hours later, they were exposed to the same context in a test session for 5 min for behavioral assessment: freezing, rearing, locomotion, grooming, and autonomic responses (fecal boluses and micturition). EB microinjection in the MRN prior to the exposure of animals to the foot shocks in the conditioning session did not alter their behavior in this session, but neutralized the association of the aversive experience to the context: there was a decrease in the expression of freezing and an increased rearing activity in the test session. This effect was reversed by prior microinjection of WAY100.635. In conclusion, EB acted on serotonergic neurons in the MRN of the ovariectomized rats, impairing the association of the aversive experience to the context, by co-modulating the functionality of somatodendritic 5-HT1A.
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Affiliation(s)
| | | | | | - Fernando Frei
- UNESP - Univ Estadual Paulista, FCL, Department of Biological Science, Avenida Dom Antonio, 2100, 19.806-900 Assis, São Paulo, Brazil
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31
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Sargin D, Oliver DK, Lambe EK. Chronic social isolation reduces 5-HT neuronal activity via upregulated SK3 calcium-activated potassium channels. eLife 2016; 5. [PMID: 27874831 PMCID: PMC5119885 DOI: 10.7554/elife.21416] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 11/02/2016] [Indexed: 01/24/2023] Open
Abstract
The activity of serotonin (5-HT) neurons is critical for mood regulation. In a mouse model of chronic social isolation, a known risk factor for depressive illness, we show that 5-HT neurons in the dorsal raphe nucleus are less responsive to stimulation. Probing the responsible cellular mechanisms pinpoints a disturbance in the expression and function of small-conductance Ca2+-activated K+ (SK) channels and reveals an important role for both SK2 and SK3 channels in normal regulation of 5-HT neuronal excitability. Chronic social isolation renders 5-HT neurons insensitive to SK2 blockade, however inhibition of the upregulated SK3 channels restores normal excitability. In vivo, we demonstrate that inhibiting SK channels normalizes chronic social isolation-induced anxiety/depressive-like behaviors. Our experiments reveal a causal link for the first time between SK channel dysregulation and 5-HT neuron activity in a lifelong stress paradigm, suggesting these channels as targets for the development of novel therapies for mood disorders.
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Affiliation(s)
- Derya Sargin
- Department of Physiology, University of Toronto, Toronto, Canada
| | - David K Oliver
- Department of Physiology, University of Toronto, Toronto, Canada
| | - Evelyn K Lambe
- Department of Physiology, University of Toronto, Toronto, Canada.,Department of Obstetrics and Gynaecology, University of Toronto, Toronto, Canada.,Department of Psychiatry, University of Toronto, Toronto, Canada
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32
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Pet-1 Switches Transcriptional Targets Postnatally to Regulate Maturation of Serotonin Neuron Excitability. J Neurosci 2016; 36:1758-74. [PMID: 26843655 DOI: 10.1523/jneurosci.3798-15.2016] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
UNLABELLED Newborn neurons enter an extended maturation stage, during which they acquire excitability characteristics crucial for development of presynaptic and postsynaptic connectivity. In contrast to earlier specification programs, little is known about the regulatory mechanisms that control neuronal maturation. The Pet-1 ETS (E26 transformation-specific) factor is continuously expressed in serotonin (5-HT) neurons and initially acts in postmitotic precursors to control acquisition of 5-HT transmitter identity. Using a combination of RNA sequencing, electrophysiology, and conditional targeting approaches, we determined gene expression patterns in maturing flow-sorted 5-HT neurons and the temporal requirements for Pet-1 in shaping these patterns for functional maturation of mouse 5-HT neurons. We report a profound disruption of postmitotic expression trajectories in Pet-1(-/-) neurons, which prevented postnatal maturation of 5-HT neuron passive and active intrinsic membrane properties, G-protein signaling, and synaptic responses to glutamatergic, lysophosphatidic, and adrenergic agonists. Unexpectedly, conditional targeting revealed a postnatal stage-specific switch in Pet-1 targets from 5-HT synthesis genes to transmitter receptor genes required for afferent modulation of 5-HT neuron excitability. Five-HT1a autoreceptor expression depended transiently on Pet-1, thus revealing an early postnatal sensitive period for control of 5-HT excitability genes. Chromatin immunoprecipitation followed by sequencing revealed that Pet-1 regulates 5-HT neuron maturation through direct gene activation and repression. Moreover, Pet-1 directly regulates the 5-HT neuron maturation factor Engrailed 1, which suggests Pet-1 orchestrates maturation through secondary postmitotic regulatory factors. The early postnatal switch in Pet-1 targets uncovers a distinct neonatal stage-specific function for Pet-1, during which it promotes maturation of 5-HT neuron excitability. SIGNIFICANCE STATEMENT The regulatory mechanisms that control functional maturation of neurons are poorly understood. We show that in addition to inducing brain serotonin (5-HT) synthesis and reuptake, the Pet-1 ETS (E26 transformation-specific) factor subsequently globally coordinates postmitotic expression trajectories of genes necessary for maturation of 5-HT neuron excitability. Further, Pet-1 switches its transcriptional targets as 5-HT neurons mature from 5-HT synthesis genes to G-protein-coupled receptors, which are necessary for afferent synaptic modulation of 5-HT neuron excitability. Our findings uncover gene-specific switching of downstream targets as a previously unrecognized regulatory strategy through which continuously expressed transcription factors control acquisition of neuronal identity at different stages of development.
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Glover ME, Clinton SM. Of rodents and humans: A comparative review of the neurobehavioral effects of early life SSRI exposure in preclinical and clinical research. Int J Dev Neurosci 2016; 51:50-72. [PMID: 27165448 PMCID: PMC4930157 DOI: 10.1016/j.ijdevneu.2016.04.008] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 04/20/2016] [Accepted: 04/20/2016] [Indexed: 02/08/2023] Open
Abstract
Selective serotonin reuptake inhibitors (SSRIs) have been a mainstay pharmacological treatment for women experiencing depression during pregnancy and postpartum for the past 25 years. SSRIs act via blockade of the presynaptic serotonin transporter and result in a transient increase in synaptic serotonin. Long-lasting changes in cellular function such as serotonergic transmission, neurogenesis, and epigenetics, are thought to underlie the therapeutic benefits of SSRIs. In recent years, though, growing evidence in clinical and preclinical settings indicate that offspring exposed to SSRIs in utero or as neonates exhibit long-lasting behavioral adaptions. Clinically, children exposed to SSRIs in early life exhibit increased internalizing behavior reduced social behavior, and increased risk for depression in adolescence. Similarly, rodents exposed to SSRIs perinatally exhibit increased traits of anxiety- or depression-like behavior. Furthermore, certain individuals appear to be more susceptible to early life SSRI exposure than others, suggesting that perinatal SSRI exposure may pose greater risks for negative outcome within certain populations. Although SSRIs trigger a number of intracellular processes that likely contribute to their therapeutic effects, early life antidepressant exposure during critical neurodevelopmental periods may elicit lasting negative effects in offspring. In this review, we cover the basic development and structure of the serotonin system, how the system is affected by early life SSRI exposure, and the behavioral outcomes of perinatal SSRI exposure in both clinical and preclinical settings. We review recent evidence indicating that perinatal SSRI exposure perturbs the developing limbic system, including altered serotonergic transmission, neurogenesis, and epigenetic processes in the hippocampus, which may contribute to behavioral domains (e.g., sociability, cognition, anxiety, and behavioral despair) that are affected by perinatal SSRI treatment. Identifying the molecular mechanisms that underlie the deleterious behavioral effects of perinatal SSRI exposure may highlight biological mechanisms in the etiology of mood disorders. Moreover, because recent studies suggest that certain individuals may be more susceptible to the negative consequences of early life SSRI exposure than others, understanding mechanisms that drive such susceptibility could lead to individualized treatment strategies for depressed women who are or plan to become pregnant.
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Affiliation(s)
| | - Sarah M Clinton
- Department of Psychiatry, University of Alabama-Birmingham, USA.
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de Paula BB, Leite-Panissi CRA. Distinct effect of 5-HT1A and 5-HT2A receptors in the medial nucleus of the amygdala on tonic immobility behavior. Brain Res 2016; 1643:152-8. [PMID: 27150816 DOI: 10.1016/j.brainres.2016.04.073] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 04/26/2016] [Accepted: 04/30/2016] [Indexed: 02/03/2023]
Abstract
The tonic immobility (TI) response is an innate fear behavior associated with intensely dangerous situations, exhibited by many species of invertebrate and vertebrate animals. In humans, it is possible that TI predicts the severity of posttraumatic stress disorder symptoms. This behavioral response is initiated and sustained by the stimulation of various groups of neurons distributed in the telencephalon, diencephalon and brainstem. Previous research has found the highest Fos-IR in the posteroventral part of the medial nucleus of the amygdala (MEA) during TI behavior; however, the neurotransmission of this amygdaloid region involved in the modulation of this innate fear behavior still needs to be clarified. Considering that a major drug class used for the treatment of psychopathology is based on serotonin (5-HT) neurotransmission, we investigated the effects of serotonergic receptor activation in the MEA on the duration of TI. The results indicate that the activation of the 5HT1A receptors or the blocking of the 5HT2 receptors of the MEA can promote a reduction in fear and/or anxiety, consequently decreasing TI duration in guinea pigs. In contrast, blocking the 5HT1A receptors or activating the 5HT2 receptors in this amygdalar region increased the TI duration, suggesting an increase in fear and/or anxiety. These alterations do not appear to be due to a modification of spontaneous motor activity, which might non-specifically affect TI duration. Thus, these results suggest a distinct role of the 5HT receptors in the MEA in innate fear modulation.
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Affiliation(s)
- Bruna Balbino de Paula
- Psychobiology Graduate Program, University of São Paulo - Ribeirão Preto Dentistry School - Dept. Morphology, Physiology and Basic Pathology 14040-901, SP, Brazil
| | - Christie Ramos Andrade Leite-Panissi
- Psychobiology Graduate Program, University of São Paulo - Ribeirão Preto Dentistry School - Dept. Morphology, Physiology and Basic Pathology 14040-901, SP, Brazil; Departament of Morphology, Physiology and Basic Pathology of Dentistry School of Ribeirão Preto, University of São Paulo, 14040-904 SP, Brazil.
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35
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Domonkos A, Nikitidou Ledri L, Laszlovszky T, Cserép C, Borhegyi Z, Papp E, Nyiri G, Freund TF, Varga V. Divergent in vivo activity of non-serotonergic and serotonergic VGluT3-neurones in the median raphe region. J Physiol 2016; 594:3775-90. [PMID: 27028801 PMCID: PMC4929318 DOI: 10.1113/jp272036] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 03/22/2016] [Indexed: 01/12/2023] Open
Abstract
KEY POINTS The median raphe is a key subcortical modulatory centre involved in several brain functions, such as regulation of the sleep-wake cycle, emotions and memory storage. A large proportion of median raphe neurones are glutamatergic and implement a radically different mode of communication compared to serotonergic cells, although their in vivo activity is unknown. We provide the first description of the in vivo, brain state-dependent firing properties of median raphe glutamatergic neurones identified by immunopositivity for the vesicular glutamate transporter type 3 (VGluT3) and serotonin (5-HT). Glutamatergic populations (VGluT3+/5-HT- and VGluT3+/5-HT+) were compared with the purely serotonergic (VGluT3-/5-HT+ and VGluT3-/5-HT-) neurones. VGluT3+/5-HT+ neurones fired similar to VGluT3-/5-HT+ cells, whereas they significantly diverged from the VGluT3+/5-HT- population. Activity of the latter subgroup resembled the spiking of VGluT3-/5-HT- cells, except for their diverging response to sensory stimulation. The VGluT3+ population of the median raphe may broadcast rapidly varying signals on top of a state-dependent, tonic modulation. ABSTRACT Subcortical modulation is crucial for information processing in the cerebral cortex. Besides the canonical neuromodulators, glutamate has recently been identified as a key cotransmitter of numerous monoaminergic projections. In the median raphe, a pure glutamatergic neurone population projecting to limbic areas was also discovered with a possibly novel, yet undetermined function. In the present study, we report the first functional description of the vesicular glutamate transporter type 3 (VGluT3)-expressing median raphe neurones. Because there is no appropriate genetic marker for the separation of serotonergic (5-HT+) and non-serotonergic (5-HT-) VGluT3+ neurones, we utilized immunohistochemistry after recording and juxtacellular labelling in anaesthetized rats. VGluT3+/5-HT- neurones fired faster, more variably and were permanently activated during sensory stimulation, as opposed to the transient response of the slow firing VGluT3-/5-HT+ subgroup. VGluT3+/5-HT- cells were also more active during hippocampal theta. In addition, the VGluT3-/5-HT- population, comprising putative GABAergic cells, resembled the firing of VGluT3+/5-HT- neurones but without any significant reaction to the sensory stimulus. Interestingly, the VGluT3+/5-HT+ group, spiking slower than the VGluT3+/5-HT- population, exhibited a mixed response (i.e. the initial transient activation was followed by a sustained elevation of firing). Phase coupling to hippocampal and prefrontal slow oscillations was found in VGluT3+/5-HT- neurones, also differentiating them from the VGluT3+/5-HT+ subpopulation. Taken together, glutamatergic neurones in the median raphe may implement multiple, highly divergent forms of modulation in parallel: a slow, tonic mode interrupted by sensory-evoked rapid transients, as well as a fast one capable of conveying complex patterns influenced by sensory inputs.
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Affiliation(s)
- Andor Domonkos
- Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary.,János Szentágothai Doctoral School of Neurosciences, Semmelweis University, Budapest, Hungary
| | - Litsa Nikitidou Ledri
- Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Tamás Laszlovszky
- Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Csaba Cserép
- Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Zsolt Borhegyi
- Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary.,Present address: MTA-ELTE-NAP B-Opto-Neuropharmacology Group, Eötvös Loránd University, Budapest, Hungary
| | - Edit Papp
- Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Gábor Nyiri
- Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Tamás F Freund
- Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Viktor Varga
- Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
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36
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You IJ, Wright SR, Garcia-Garcia AL, Tapper AR, Gardner PD, Koob GF, David Leonardo E, Bohn LM, Wee S. 5-HT1A Autoreceptors in the Dorsal Raphe Nucleus Convey Vulnerability to Compulsive Cocaine Seeking. Neuropsychopharmacology 2016; 41:1210-22. [PMID: 26324408 PMCID: PMC4793105 DOI: 10.1038/npp.2015.268] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 08/02/2015] [Accepted: 08/11/2015] [Indexed: 11/09/2022]
Abstract
Cocaine addiction and depression are comorbid disorders. Although it is well recognized that 5-hydroxytryptamine (5-HT; serotonin) plays a central role in depression, our understanding of its role in addiction is notably lacking. The 5-HT system in the brain is carefully controlled by a combined process of regulating 5-HT neuron firing through 5-HT autoreceptors, neurotransmitter release, enzymatic degradation, and reuptake by transporters. This study tests the hypothesis that activation of 5-HT1A autoreceptors, which would lessen 5-HT neuron firing, contributes to cocaine-seeking behaviors. Using 5-HT neuron-specific reduction of 5-HT1A autoreceptor gene expression in mice, we demonstrate that 5-HT1A autoreceptors are necessary for cocaine conditioned place preference. In addition, using designer receptors exclusively activated by designer drugs (DREADDs) technology, we found that stimulation of the serotonergic dorsal raphe nucleus (DRN) afferents to the nucleus accumbens (NAc) abolishes cocaine reward and promotes antidepressive-like behaviors. Finally, using a rat model of compulsive-like cocaine self-administration, we found that inhibition of dorsal raphe 5-HT1A autoreceptors attenuates cocaine self-administration in rats with 6 h extended access, but not 1 h access to the drug. Therefore, our findings suggest an important role for 5-HT1A autoreceptors, and thus DRNNAc 5-HT neuronal activity, in the etiology and vulnerability to cocaine reward and addiction. Moreover, our findings support a strategy for antagonizing 5-HT1A autoreceptors for treating cocaine addiction.
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Affiliation(s)
- In-Jee You
- Department of Psychiatry, Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, MA, USA,Department of Molecular Therapeutics, The Scripps Research Institute-Florida, Jupiter, FL, USA,Department of Psychiatry, Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, MA 01604, USA, Tel: +1 508 455 4293, Fax: +1 508 455 4281, E-mail:
| | - Sherie R Wright
- Department of Molecular Therapeutics, The Scripps Research Institute-Florida, Jupiter, FL, USA
| | | | - Andrew R Tapper
- Department of Psychiatry, Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Paul D Gardner
- Department of Psychiatry, Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - George F Koob
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, CA, USA,National Institute on Alcohol Abuse and Alcoholism, Rockville, MD, USA
| | - E David Leonardo
- Department of Psychiatry, Columbia University, New York, NY, USA,New York State Psychiatric Institute, New York, NY, USA
| | - Laura M Bohn
- Department of Molecular Therapeutics, The Scripps Research Institute-Florida, Jupiter, FL, USA
| | - Sunmee Wee
- Department of Molecular Therapeutics, The Scripps Research Institute-Florida, Jupiter, FL, USA
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37
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Ye R, Quinlan MA, Iwamoto H, Wu HH, Green NH, Jetter CS, McMahon DG, Veestra-VanderWeele J, Levitt P, Blakely RD. Physical Interactions and Functional Relationships of Neuroligin 2 and Midbrain Serotonin Transporters. Front Synaptic Neurosci 2016; 7:20. [PMID: 26793096 PMCID: PMC4707279 DOI: 10.3389/fnsyn.2015.00020] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 12/14/2015] [Indexed: 12/31/2022] Open
Abstract
The neurotransmitter serotonin [5-hydroxytryptamine (5-HT)] modulates many key brain functions including those subserving sensation, emotion, reward, and cognition. Efficient clearance of 5-HT after release is achieved by the antidepressant-sensitive 5-HT transporter (SERT, SLC6A4). To identify novel SERT regulators, we pursued a proteomic analysis of mouse midbrain SERT complexes, evaluating findings in the context of prior studies that established a SERT-linked transcriptome. Remarkably, both efforts converged on a relationship of SERT with the synaptic adhesion protein neuroligin 2 (NLGN2), a post-synaptic partner for presynaptic neurexins, and a protein well-known to organize inhibitory GABAergic synapses. Western blots of midbrain reciprocal immunoprecipitations confirmed SERT/NLGN2 associations, and also extended to other NLGN2 associated proteins [e.g., α-neurexin (NRXN), gephyrin]. Midbrain SERT/NLGN2 interactions were found to be Ca(2+)-independent, supporting cis vs. trans-synaptic interactions, and were absent in hippocampal preparations, consistent with interactions arising in somatodendritic compartments. Dual color in situ hybridization confirmed co-expression of Tph2 and Nlgn2 mRNA in the dorsal raphe, with immunocytochemical studies confirming SERT:NLGN2 co-localization in raphe cell bodies but not axons. Consistent with correlative mRNA expression studies, loss of NLGN2 expression in Nlgn2 null mice produced significant reductions in midbrain and hippocampal SERT expression and function. Additionally, dorsal raphe 5-HT neurons from Nlgn2 null mice exhibit reduced excitability, a loss of GABAA receptor-mediated IPSCs, and increased 5-HT1A autoreceptor sensitivity. Finally, Nlgn2 null mice display significant changes in behaviors known to be responsive to SERT and/or 5-HT receptor manipulations. We discuss our findings in relation to the possible coordination of intrinsic and extrinsic regulation afforded by somatodendritic SERT:NLGN2 complexes.
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Affiliation(s)
- Ran Ye
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville TN, USA
| | - Meagan A Quinlan
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville TN, USA
| | - Hideki Iwamoto
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville TN, USA
| | - Hsiao-Huei Wu
- Department of Psychiatry, Vanderbilt University School of Medicine, Nashville TN, USA
| | - Noah H Green
- Department of Biological Sciences, Vanderbilt University School of Medicine, Nashville TN, USA
| | - Christopher S Jetter
- Department of Psychiatry, Vanderbilt University School of Medicine, Nashville TN, USA
| | - Douglas G McMahon
- Department of Pharmacology, Vanderbilt University School of Medicine, NashvilleTN, USA; Department of Biological Sciences, Vanderbilt University School of Medicine, NashvilleTN, USA
| | - Jeremy Veestra-VanderWeele
- Department of Psychiatry, NYS Psychiatric Institute, Columbia University Medical Center, New York NY, USA
| | - Pat Levitt
- Department of Psychiatry, Vanderbilt University School of Medicine, Nashville TN, USA
| | - Randy D Blakely
- Department of Pharmacology, Vanderbilt University School of Medicine, NashvilleTN, USA; Department of Psychiatry, Vanderbilt University School of Medicine, NashvilleTN, USA
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Fernandez SP, Cauli B, Cabezas C, Muzerelle A, Poncer JC, Gaspar P. Multiscale single-cell analysis reveals unique phenotypes of raphe 5-HT neurons projecting to the forebrain. Brain Struct Funct 2015; 221:4007-4025. [PMID: 26608830 DOI: 10.1007/s00429-015-1142-4] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 11/02/2015] [Indexed: 11/28/2022]
Abstract
Serotonergic neurons of the raphe nuclei exhibit anatomical, neurochemical and elecrophysiological heterogeneity that likely underpins their specific role in multiple behaviors. However, the precise organization of serotonin (5-HT) neurons to orchestrate 5-HT release patterns throughout the brain is not well understood. We compared the electrophysiological and neurochemical properties of dorsal and median raphe 5-HT neurons projecting to the medial prefrontal cortex (mPFC), amygdala (BLA) and dorsal hippocampus (dHP), combining retrograde tract tracing with brain slice electrophysiology and single-cell RT-PCR in Pet1-EGFP mice. Our results show that 5-HT neurons projecting to the dHP and the mPFC and the BLA form largely non-overlapping populations and that BLA-projecting neurons have characteristic excitability and membrane properties. In addition, using an unbiased clustering method that correlates anatomical, molecular and electrophysiological phenotypes, we find that 5-HT neurons with projections to the mPFC and the dHP segregate from those projecting to the BLA. Single-cell gene profiling showed a restricted expression of the peptide galanin in the population of 5-HT neurons projecting to the mPFC. Finally, cluster analysis allowed identifying an atypical subtype of 5-HT neuron with low excitability, long firing delays and preferential expression of the vesicular glutamate transporter type 3. Overall, these findings allow to define correlated anatomical and physiological identities of serotonin raphe neurons that help understanding how discrete raphe cells subpopulations account for the heterogeneous activities of the midbrain serotonergic system.
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Affiliation(s)
- Sebastian Pablo Fernandez
- Institut du Fer à Moulin, INSERM U839, 17 rue du Fer à Moulin, 75005, Paris, France. .,Université Pierre et Marie Curie, Paris, France. .,Institut du Fer a Moulin, Paris, France.
| | - Bruno Cauli
- Université Pierre et Marie Curie, Paris, France.,CNRS, UMR 8246, Neuroscience Paris Seine, 75005, Paris, France.,Inserm UMR-S 1130, Neuroscience Paris Seine, 75005, Paris, France
| | - Carolina Cabezas
- Institut du Fer à Moulin, INSERM U839, 17 rue du Fer à Moulin, 75005, Paris, France.,Université Pierre et Marie Curie, Paris, France.,Institut du Fer a Moulin, Paris, France
| | - Aude Muzerelle
- Institut du Fer à Moulin, INSERM U839, 17 rue du Fer à Moulin, 75005, Paris, France.,Université Pierre et Marie Curie, Paris, France.,Institut du Fer a Moulin, Paris, France
| | - Jean-Christophe Poncer
- Institut du Fer à Moulin, INSERM U839, 17 rue du Fer à Moulin, 75005, Paris, France.,Université Pierre et Marie Curie, Paris, France.,Institut du Fer a Moulin, Paris, France
| | - Patricia Gaspar
- Institut du Fer à Moulin, INSERM U839, 17 rue du Fer à Moulin, 75005, Paris, France. .,Université Pierre et Marie Curie, Paris, France. .,Institut du Fer a Moulin, Paris, France.
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Kusek M, Sowa J, Kamińska K, Gołembiowska K, Tokarski K, Hess G. 5-HT7 receptor modulates GABAergic transmission in the rat dorsal raphe nucleus and controls cortical release of serotonin. Front Cell Neurosci 2015; 9:324. [PMID: 26347612 PMCID: PMC4539517 DOI: 10.3389/fncel.2015.00324] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 08/05/2015] [Indexed: 01/17/2023] Open
Abstract
The 5-HT7 receptor is one of the several serotonin (5-HT) receptor subtypes that are expressed in the dorsal raphe nucleus (DRN). Some earlier findings suggested that 5-HT7 receptors in the DRN were localized on GABAergic interneurons modulating the activity of 5-HT projection neurons. The aim of the present study was to find out how the 5-HT7 receptor modulates the GABAergic synaptic input to putative 5-HT DRN neurons, and whether blockade of the 5-HT7 receptor would affect the release of 5-HT in the target structure. Male Wistar rats with microdialysis probes implanted in the prefrontal cortex (PFC) received injections of the 5-HT7 receptor antagonist (2R)-1-[(3-hydroxyphenyl)sulfonyl]-2-[2-(4-methyl-1-piperidinyl)ethyl]pyrrolidine hydrochloride (SB 269970), which induced an increase in the levels of 5-HT and its metabolite, 5-hydroxyindoleacetic acid (5-HIAA) in the PFC. In another set of experiments whole-cell recordings from presumed projection neurons were carried out using DRN slices. SB 269970 application resulted in depolarization and in an increase in the firing frequency of the cells. In order to activate 5-HT7 receptors, 5-carboxamidotryptamine (5-CT) was applied in the presence of N-[2-[4-(2-methoxyphenyl)-1piperazinyl]ethyl]-N-2-pyridinylcyclohexanecarboxamide (WAY100635). Hyperpolarization of cells and a decrease in the firing frequency were observed after activation of the 5-HT7 receptor. Blockade of 5-HT7 receptors caused a decrease in the mean frequency of spontaneous inhibitory postsynaptic currents (sIPSCs), while its activation induced an increase. The mechanism of these effects appears to involve tonically-active 5-HT7 receptors modulating firing and/or GABA release from inhibitory interneurons which regulate the activity of DRN serotonergic projection neurons.
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Affiliation(s)
- Magdalena Kusek
- Department of Physiology, Institute of Pharmacology, Polish Academy of Sciences Krakow, Poland
| | - Joanna Sowa
- Department of Physiology, Institute of Pharmacology, Polish Academy of Sciences Krakow, Poland
| | - Katarzyna Kamińska
- Department of Pharmacology, Institute of Pharmacology, Polish Academy of Sciences Krakow, Poland
| | - Krystyna Gołembiowska
- Department of Pharmacology, Institute of Pharmacology, Polish Academy of Sciences Krakow, Poland
| | - Krzysztof Tokarski
- Department of Physiology, Institute of Pharmacology, Polish Academy of Sciences Krakow, Poland
| | - Grzegorz Hess
- Department of Physiology, Institute of Pharmacology, Polish Academy of Sciences Krakow, Poland ; Institute of Zoology, Jagiellonian University Krakow, Poland
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Hainer C, Mosienko V, Koutsikou S, Crook JJ, Gloss B, Kasparov S, Lumb BM, Alenina N. Beyond Gene Inactivation: Evolution of Tools for Analysis of Serotonergic Circuitry. ACS Chem Neurosci 2015; 6:1116-29. [PMID: 26132472 DOI: 10.1021/acschemneuro.5b00045] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
In the brain, serotonin (5-hydroxytryptamine, 5-HT) controls a multitude of physiological and behavioral functions. Serotonergic neurons in the raphe nuclei give rise to a complex and extensive network of axonal projections throughout the whole brain. A major challenge in the analysis of these circuits is to understand how the serotonergic networks are linked to the numerous functions of this neurotransmitter. In the past, many studies employed approaches to inactivate different genes involved in serotonergic neuron formation, 5-HT transmission, or 5-HT metabolism. Although these approaches have contributed significantly to our understanding of serotonergic circuits, they usually result in life-long gene inactivation. As a consequence, compensatory changes in serotonergic and other neurotransmitter systems may occur and complicate the interpretation of the observed phenotypes. To dissect the complexity of the serotonergic system with greater precision, approaches to reversibly manipulate subpopulations of serotonergic neurons are required. In this review, we summarize findings on genetic animal models that enable control of 5-HT neuronal activity or mapping of the serotonergic system. This includes a comparative analysis of several mouse and rat lines expressing Cre or Flp recombinases under Tph2, Sert, or Pet1 promoters with a focus on specificity and recombination efficiency. We further introduce applications for Cre-mediated cell-type specific gene expression to optimize spatial and temporal precision for the manipulation of serotonergic neurons. Finally, we discuss other temporally regulated systems, such as optogenetics and designer receptors exclusively activated by designer drugs (DREADD) approaches to control 5-HT neuron activity.
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Affiliation(s)
- Cornelia Hainer
- Max-Delbrück-Center for Molecular Medicine (MDC), Berlin 13125, Germany
| | | | | | | | - Bernd Gloss
- National Institute of Environmental Health Science, Durham, North Carolina 27709, United States
| | | | | | - Natalia Alenina
- Max-Delbrück-Center for Molecular Medicine (MDC), Berlin 13125, Germany
- Institute
of Translational Biomedicine, St. Petersburg State University, St. Petersburg 199034, Russia
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Beliveau V, Svarer C, Frokjaer VG, Knudsen GM, Greve DN, Fisher PM. Functional connectivity of the dorsal and median raphe nuclei at rest. Neuroimage 2015; 116:187-95. [PMID: 25963733 DOI: 10.1016/j.neuroimage.2015.04.065] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 03/31/2015] [Accepted: 04/28/2015] [Indexed: 10/23/2022] Open
Abstract
Serotonin (5-HT) is a neurotransmitter critically involved in a broad range of brain functions and implicated in the pathophysiology of neuropsychiatric illnesses including major depression, anxiety and sleep disorders. Despite being widely distributed throughout the brain, there is limited knowledge on the contribution of 5-HT to intrinsic brain activity. The dorsal raphe (DR) and median raphe (MR) nuclei are the source of most serotonergic neurons projecting throughout the brain and thus provide a compelling target for a seed-based probe of resting-state activity related to 5-HT. Here we implemented a novel multimodal neuroimaging approach for investigating resting-state functional connectivity (FC) between DR and MR and cortical, subcortical and cerebellar target areas. Using [(11)C]DASB positron emission tomography (PET) images of the brain serotonin transporter (5-HTT) combined with structural MRI from 49 healthy volunteers, we delineated DR and MR and performed a seed-based resting-state FC analysis. The DR and MR seeds produced largely similar FC maps: significant positive FC with brain regions involved in cognitive and emotion processing including anterior cingulate, amygdala, insula, hippocampus, thalamus, basal ganglia and cerebellum. Significant negative FC was observed within pre- and postcentral gyri for the DR but not for the MR seed. We observed a significant association between DR and MR FC and regional 5-HTT binding. Our results provide evidence for a resting-state network related to DR and MR and comprising regions receiving serotonergic innervation and centrally involved in 5-HT related behaviors including emotion, cognition and reward processing. These findings provide a novel advance in estimating resting-state FC related to 5-HT signaling, which can benefit our understanding of its role in behavior and neuropsychiatric illnesses.
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Affiliation(s)
- Vincent Beliveau
- Neurobiology Research Unit and Center for Integrated Molecular Brain Imaging, Rigshospitalet, Copenhagen, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Claus Svarer
- Neurobiology Research Unit and Center for Integrated Molecular Brain Imaging, Rigshospitalet, Copenhagen, Denmark
| | - Vibe G Frokjaer
- Neurobiology Research Unit and Center for Integrated Molecular Brain Imaging, Rigshospitalet, Copenhagen, Denmark
| | - Gitte M Knudsen
- Neurobiology Research Unit and Center for Integrated Molecular Brain Imaging, Rigshospitalet, Copenhagen, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Douglas N Greve
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA
| | - Patrick M Fisher
- Neurobiology Research Unit and Center for Integrated Molecular Brain Imaging, Rigshospitalet, Copenhagen, Denmark.
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Llamosas N, Bruzos-Cidón C, Rodríguez JJ, Ugedo L, Torrecilla M. Deletion of GIRK2 Subunit of GIRK Channels Alters the 5-HT1A Receptor-Mediated Signaling and Results in a Depression-Resistant Behavior. Int J Neuropsychopharmacol 2015; 18:pyv051. [PMID: 25956878 PMCID: PMC4756724 DOI: 10.1093/ijnp/pyv051] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Accepted: 05/04/2015] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Targeting dorsal raphe 5-HT1A receptors, which are coupled to G-protein inwardly rectifying potassium (GIRK) channels, has revealed their contribution not only to behavioral and functional aspects of depression but also to the clinical response to its treatment. Although GIRK channels containing GIRK2 subunits play an important role controlling excitability of several brain areas, their impact on the dorsal raphe activity is still unknown. Thus, the goal of the present study was to investigate the involvement of GIRK2 subunit-containing GIRK channels in depression-related behaviors and physiology of serotonergic neurotransmission. METHODS Behavioral, functional, including in vivo extracellular recordings of dorsal raphe neurons, and neurogenesis studies were carried out in wild-type and GIRK2 mutant mice. RESULTS Deletion of the GIRK2 subunit promoted a depression-resistant phenotype and determined the behavioral response to the antidepressant citalopram without altering hippocampal neurogenesis. In dorsal raphe neurons of GIRK2 knockout mice, and also using GIRK channel blocker tertiapin-Q, the basal firing rate was higher than that obtained in wild-type animals, although no differences were observed in other firing parameters. 5-HT1A receptors were desensitized in GIRK2 knockout mice, as demonstrated by a lower sensitivity of dorsal raphe neurons to the inhibitory effect of the 5-HT1A receptor agonist, 8-OH-DPAT, and the antidepressant citalopram. CONCLUSIONS Our results indicate that GIRK channels formed by GIRK2 subunits determine depression-related behaviors as well as basal and 5-HT1A receptor-mediated dorsal raphe neuronal activity, becoming alternative therapeutic targets for psychiatric diseases underlying dysfunctional serotonin transmission.
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Affiliation(s)
| | | | | | | | - Maria Torrecilla
- Department of Pharmacology, Faculty of Medicine and Dentistry, University of the Basque Country UPV/EHU, Leioa, Spain (Drs Llamosas, Bruzos-Cidón, Ugedo, and Torrecilla); Achucarro Center for Neuroscience, IKERBASQUE, Basque Foundation for Science, Bilbao, Spain (Dr Rodríguez); Department of Neuroscience, University of the Basque Country UPV/EHU and CIBERNED, Leioa, Spain (Dr Rodríguez).
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Pezzato FA, Can A, Hoshino K, Horta JDAC, Mijares MG, Gould TD. Effect of lithium on behavioral disinhibition induced by electrolytic lesion of the median raphe nucleus. Psychopharmacology (Berl) 2015; 232:1441-50. [PMID: 25345734 PMCID: PMC4388762 DOI: 10.1007/s00213-014-3775-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Accepted: 10/13/2014] [Indexed: 11/28/2022]
Abstract
RATIONALE Alterations in brainstem circuits have been proposed as a possible mechanism underlying the etiology of mood disorders. Projections from the median raphe nucleus (MnR) modulate dopaminergic activity in the forebrain and are also part of a behavioral disinhibition/inhibition system that produces phenotypes resembling behavioral variations manifested during manic and depressive phases of bipolar disorder. OBJECTIVE The aim of this study is to assess the effect of chronic lithium treatment on behavioral disinhibition induced by MnR lesions. METHODS MnR electrolytic lesions were performed in C57BL/6J mice, with sham-operated and intact animals as control groups. Following recovery, mice were chronically treated with lithium (LiCl, added in chow) followed by behavioral testing. RESULTS MnR lesion induced manic-like behavioral alterations including hyperactivity in the open field (OF), stereotyped circling, anxiolytic/risk taking in the elevated plus maze (EPM) and light/dark box (LDB) tests, and increased basal body temperature. Lithium was specifically effective in reducing OF hyperactivity and stereotypy but did not reverse (EPM) or had a nonspecific effect (LDB) on anxiety/risk-taking measures. Additionally, lithium decreased saccharin preference and prevented weight loss during single housing. CONCLUSIONS Our data support electrolytic lesions of the MnR as an experimental model of a hyper-excitable/disinhibited phenotype consistent with some aspects of mania that are attenuated by the mood stabilizer lithium. Given lithium's relatively specific efficacy in treating mania, these data support the hypothesis that manic symptoms derive not only from the stimulation of excitatory systems but also from inactivation or decreased activity of inhibitory mechanisms.
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Craige CP, Lewandowski S, Kirby LG, Unterwald EM. Dorsal raphe 5-HT(2C) receptor and GABA networks regulate anxiety produced by cocaine withdrawal. Neuropharmacology 2015; 93:41-51. [PMID: 25656481 DOI: 10.1016/j.neuropharm.2015.01.021] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 01/21/2015] [Accepted: 01/22/2015] [Indexed: 01/17/2023]
Abstract
The serotonin system is intimately linked to both the mediation of anxiety and long-term effects of cocaine, potentially through interaction of inhibitory 5-HT2C receptor and gamma-aminobutyric acid (GABA) networks. This study characterized the function of the dorsal raphe (DR) 5-HT2C receptor and GABA network in anxiety produced by chronic cocaine withdrawal. C57BL/6 mice were injected with saline or cocaine (15 mg/kg) 3 times daily for 10 days, and tested on the elevated plus maze 30 min, 25 h, or 7 days after the last injection. Cocaine-withdrawn mice showed heightened anxiety-like behavior at 25 h of withdrawal, as compared to saline controls. Anxiety-like behavior was not different when mice were tested 30 min or 7 days after the last cocaine injection. Electrophysiology data revealed that serotonin cells from cocaine-withdrawn mice exhibited increased GABA inhibitory postsynaptic currents (IPSCs) in specific DR subregions dependent on withdrawal time (25 h or 7 d), an effect that was absent in cells from non-withdrawn mice (30 min after the last cocaine injection). Increased IPSC activity was restored to baseline levels following bath application of the 5-HT2C receptor antagonist, SB 242084. In a separate cohort of cocaine-injected mice at 25 h of withdrawal, both global and intra-DR blockade of 5-HT2C receptors prior to elevated plus maze testing attenuated anxiety-like behavior. This study demonstrates that DR 5-HT2C receptor blockade prevents anxiety-like behavior produced by cocaine withdrawal, potentially through attenuation of heightened GABA activity, supporting a role for the 5-HT2C receptor in mediating anxiety produced by cocaine withdrawal.
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Affiliation(s)
- Caryne P Craige
- Department of Pharmacology, Temple University School of Medicine, Philadelphia, PA, USA; Center for Substance Abuse Research, Temple University School of Medicine, Philadelphia, PA, USA.
| | - Stacia Lewandowski
- Center for Substance Abuse Research, Temple University School of Medicine, Philadelphia, PA, USA
| | - Lynn G Kirby
- Department of Anatomy and Cell Biology, Temple University School of Medicine, Philadelphia, PA, USA; Center for Substance Abuse Research, Temple University School of Medicine, Philadelphia, PA, USA
| | - Ellen M Unterwald
- Department of Pharmacology, Temple University School of Medicine, Philadelphia, PA, USA; Center for Substance Abuse Research, Temple University School of Medicine, Philadelphia, PA, USA
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45
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Olivier B. Serotonin: a never-ending story. Eur J Pharmacol 2014; 753:2-18. [PMID: 25446560 DOI: 10.1016/j.ejphar.2014.10.031] [Citation(s) in RCA: 166] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 10/12/2014] [Accepted: 10/16/2014] [Indexed: 12/30/2022]
Abstract
The neurotransmitter serotonin is an evolutionary ancient molecule that has remarkable modulatory effects in almost all central nervous system integrative functions, such as mood, anxiety, stress, aggression, feeding, cognition and sexual behavior. After giving a short outline of the serotonergic system (anatomy, receptors, transporter) the author's contributions over the last 40 years in the role of serotonin in depression, aggression, anxiety, stress and sexual behavior is outlined. Each area delineates the work performed on animal model development, drug discovery and development. Most of the research work described has started from an industrial perspective, aimed at developing animals models for psychiatric diseases and leading to putative new innovative psychotropic drugs, like in the cases of the SSRI fluvoxamine, the serenic eltoprazine and the anxiolytic flesinoxan. Later this research work mainly focused on developing translational animal models for psychiatric diseases and implicating them in the search for mechanisms involved in normal and diseased brains and finding new concepts for appropriate drugs.
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Affiliation(s)
- Berend Olivier
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences & Brain Center Rudolf Magnus, Utrecht University, Universiteitsweg 99, 3584CG Utrecht, The Netherlands; Department of Psychiatry, Yale University School of Medicine, New Haven, USA
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Prevention of alcohol-heightened aggression by CRF-R1 antagonists in mice: critical role for DRN-PFC serotonin pathway. Neuropsychopharmacology 2014; 39:2874-83. [PMID: 24917195 PMCID: PMC4200498 DOI: 10.1038/npp.2014.139] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Revised: 06/03/2014] [Accepted: 06/05/2014] [Indexed: 12/22/2022]
Abstract
Alcohol can escalate aggressive behavior in a significant subgroup of rodents, humans, and nonhuman primates. The present study investigated whether blockade of corticotropin-releasing factor receptor type 1 (CRF-R1) could prevent the emergence of alcohol-heightened aggression in mice. The serotonin (5-HT) pathway from the dorsal raphe nucleus (DRN) to the medial prefrontal cortex (mPFC) by CRF-R1 was investigated as a possible target for the prevention of alcohol-heightened aggressive behavior. Male CFW mice that reliably exhibited aggressive behaviors after consuming 1 g/kg of alcohol received systemic or intra-DRN administration of CRF-R1 antagonists, CP-154,526 or MTIP, before a confrontation with a male conspecific. Blockade of DRN CRF-R1 receptors with both antagonists significantly reduced only alcohol-heightened aggression, whereas systemic administration reduced both alcohol-heightened and species-typical aggression. Next, a 5-HT1A agonist, 8-OH-DPAT, was coadministered with CP-154,526 into the DRN to temporarily disrupt 5-HT activity. This manipulation abolished the antiaggressive effects of intra-DRN CP-154,526. In the mPFC, in vivo microdialysis revealed that extracellular 5-HT levels were increased in mice that consumed alcohol and were then injected with CP-154,526, both systemically or intra-DRN. Neither alcohol nor CP-154,526 alone affected 5-HT release in the mPFC. The present results suggest the DRN as a critical site for CRF-R1 to modulate alcohol-heightened aggression via action on the serotonergic DRN-PFC pathway.
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47
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Serotonin in anxiety and panic: Contributions of the elevated T-maze. Neurosci Biobehav Rev 2014; 46 Pt 3:397-406. [DOI: 10.1016/j.neubiorev.2014.03.007] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 02/05/2014] [Accepted: 03/03/2014] [Indexed: 11/21/2022]
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48
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Loveland JL, Uy N, Maruska KP, Carpenter RE, Fernald RD. Social status differences regulate the serotonergic system of a cichlid fish, Astatotilapia burtoni. ACTA ACUST UNITED AC 2014; 217:2680-90. [PMID: 24855673 DOI: 10.1242/jeb.100685] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Serotonin (5-HT) inhibits aggression and modulates aspects of sexual behaviour in many species, but the mechanisms responsible are not well understood. Here, we exploited the social dominance hierarchy of Astatotilapia burtoni to understand the role of the serotonergic system in long-term maintenance of social status. We identified three populations of 5-HT cells in dorsal and ventral periventricular pretectal nuclei (PPd, PPv), the nucleus of the paraventricular organ (PVO) and raphe. Dominant males had more 5-HT cells than subordinates in the raphe, but the size of these cells did not differ between social groups. Subordinates had higher serotonergic turnover in the raphe and preoptic area (POA), a nucleus essential for hypothalamic-pituitary-gonadal (HPG) axis function. The relative abundance of mRNAs for 5-HT receptor (5-HTR) subtypes 1A and 2A (htr1a, htr2a) was higher in subordinates, a difference restricted to the telencephalon. Because social status is tightly linked to reproductive capacity, we asked whether serotonin turnover and the expression of its receptors correlated with testes size and circulating levels of 11-ketotestosterone (11-KT). We found negative correlations between both raphe and POA serotonin turnover and testes size, as well as between htr1a mRNA levels and circulating 11-KT. Thus, increased serotonin turnover in non-aggressive males is restricted to specific brain nuclei and is associated with increased expression of 5-HTR subtypes 1A and 2A exclusively in the telencephalon.
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Affiliation(s)
- Jasmine L Loveland
- Department of Biological Sciences, Stanford University, Stanford, CA 94305, USA
| | - Natalie Uy
- Department of Biological Sciences, Stanford University, Stanford, CA 94305, USA
| | - Karen P Maruska
- Department of Biological Sciences, Stanford University, Stanford, CA 94305, USA
| | - Russ E Carpenter
- Department of Biological Sciences, Stanford University, Stanford, CA 94305, USA
| | - Russell D Fernald
- Department of Biological Sciences, Stanford University, Stanford, CA 94305, USA
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Masseck OA, Spoida K, Dalkara D, Maejima T, Rubelowski JM, Wallhorn L, Deneris ES, Herlitze S. Vertebrate cone opsins enable sustained and highly sensitive rapid control of Gi/o signaling in anxiety circuitry. Neuron 2014; 81:1263-1273. [PMID: 24656249 DOI: 10.1016/j.neuron.2014.01.041] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/21/2014] [Indexed: 10/25/2022]
Abstract
G protein-coupled receptors (GPCRs) coupling to Gi/o signaling pathways are involved in the control of important physiological functions, which are difficult to investigate because of the limitation of tools to control the signaling pathway with precise kinetics and specificity. We established two vertebrate cone opsins, short- and long-wavelength opsin, for long-lasting and repetitive activation of Gi/o signaling pathways in vitro and in vivo. We demonstrate for both opsins the repetitive fast, membrane-delimited, ultra light-sensitive, and wavelength-dependent activation of the Gi/o pathway in HEK cells. We also show repetitive control of Gi/o pathway activation in 5-HT1A receptor domains in the dorsal raphe nucleus (DRN) in brain slices and in vivo, which is sufficient to modulate anxiety behavior in mice. Thus, vertebrate cone opsins represent a class of tools for understanding the role of Gi/o-coupled GPCRs in health and disease.
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Affiliation(s)
- Olivia A Masseck
- Department of General Zoology and Neurobiology, ND7/31, Ruhr-University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Katharina Spoida
- Department of General Zoology and Neurobiology, ND7/31, Ruhr-University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Deniz Dalkara
- INSERM, U968, Sorbonne Universités, UPMC Univ Paris 06, UMR_S 968, CNRS, UMR_7210 Institut de la Vision, Paris, F-75012, France
| | - Takashi Maejima
- Department of General Zoology and Neurobiology, ND7/31, Ruhr-University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Johanna M Rubelowski
- Department of General Zoology and Neurobiology, ND7/31, Ruhr-University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Lutz Wallhorn
- Department of General Zoology and Neurobiology, ND7/31, Ruhr-University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Evan S Deneris
- Department of Neurosciences, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Stefan Herlitze
- Department of General Zoology and Neurobiology, ND7/31, Ruhr-University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany.
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Tuckwell HC, Penington NJ. Computational modeling of spike generation in serotonergic neurons of the dorsal raphe nucleus. Prog Neurobiol 2014; 118:59-101. [PMID: 24784445 DOI: 10.1016/j.pneurobio.2014.04.001] [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: 10/11/2012] [Revised: 04/14/2014] [Accepted: 04/21/2014] [Indexed: 01/14/2023]
Abstract
Serotonergic neurons of the dorsal raphe nucleus, with their extensive innervation of limbic and higher brain regions and interactions with the endocrine system have important modulatory or regulatory effects on many cognitive, emotional and physiological processes. They have been strongly implicated in responses to stress and in the occurrence of major depressive disorder and other psychiatric disorders. In order to quantify some of these effects, detailed mathematical models of the activity of such cells are required which describe their complex neurochemistry and neurophysiology. We consider here a single-compartment model of these neurons which is capable of describing many of the known features of spike generation, particularly the slow rhythmic pacemaking activity often observed in these cells in a variety of species. Included in the model are 11 kinds of ion channels: a fast sodium current INa, a delayed rectifier potassium current IKDR, a transient potassium current IA, a slow non-inactivating potassium current IM, a low-threshold calcium current IT, two high threshold calcium currents IL and IN, small and large conductance potassium currents ISK and IBK, a hyperpolarization-activated cation current IH and a leak current ILeak. In Sections 3-8, each current type is considered in detail and parameters estimated from voltage clamp data where possible. Three kinds of model are considered for the BK current and two for the leak current. Intracellular calcium ion concentration Cai is an additional component and calcium dynamics along with buffering and pumping is discussed in Section 9. The remainder of the article contains descriptions of computed solutions which reveal both spontaneous and driven spiking with several parameter sets. Attention is focused on the properties usually associated with these neurons, particularly long duration of action potential, steep upslope on the leading edge of spikes, pacemaker-like spiking, long-lasting afterhyperpolarization and the ramp-like return to threshold after a spike. In some cases the membrane potential trajectories display doublets or have humps or notches as have been reported in some experimental studies. The computed time courses of IA and IT during the interspike interval support the generally held view of a competition between them in influencing the frequency of spiking. Spontaneous activity was facilitated by the presence of IH which has been found in these neurons by some investigators. For reasonable sets of parameters spike frequencies between about 0.6Hz and 1.2Hz are obtained, but frequencies as high as 6Hz could be obtained with special parameter choices. Topics investigated and compared with experiment include shoulders, notches, anodal break phenomena, the effects of noradrenergic input, frequency versus current curves, depolarization block, effects of cell size and the effects of IM. The inhibitory effects of activating 5-HT1A autoreceptors are also investigated. There is a considerable discussion of in vitro versus in vivo firing behavior, with focus on the roles of noradrenergic input, corticotropin-releasing factor and orexinergic inputs. Location of cells within the nucleus is probably a major factor, along with the state of the animal.
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Affiliation(s)
- Henry C Tuckwell
- Max Planck Institute for Mathematics in the Sciences, Inselstr. 22, 04103 Leipzig, Germany; School of Electrical and Electronic Engineering, University of Adelaide, Adelaide, South Australia 5005, Australia.
| | - Nicholas J Penington
- Department of Physiology and Pharmacology, State University of New York, Downstate Medical Center, Box 29, 450 Clarkson Avenue, Brooklyn, NY 11203-2098, USA; Program in Neural and Behavioral Science and Robert F. Furchgott Center for Neural and Behavioral Science, State University of New York, Downstate Medical Center, Box 29, 450 Clarkson Avenue, Brooklyn, NY 11203-2098, USA
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