1
|
Wang Z, Yueh H, Chau M, Veenstra-VanderWeele J, O'Reilly KC. Circuits underlying social function and dysfunction. Autism Res 2023; 16:1268-1288. [PMID: 37458578 DOI: 10.1002/aur.2978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 06/13/2023] [Indexed: 08/01/2023]
Abstract
Substantial advances have been made toward understanding the genetic and environmental risk factors for autism, a neurodevelopmental disorder with social impairment as a core feature. In combination with optogenetic and chemogenetic tools to manipulate neural circuits in vivo, it is now possible to use model systems to test how specific neural circuits underlie social function and dysfunction. Here, we review the literature that has identified circuits associated with social interest (sociability), social reward, social memory, dominance, and aggression, and we outline a preliminary roadmap of the neural circuits driving these social behaviors. We highlight the neural circuitry underlying each behavioral domain, as well as develop an interactive map of how these circuits overlap across domains. We find that some of the circuits underlying social behavior are general and are involved in the control of multiple behavioral aspects, whereas other circuits appear to be specialized for specific aspects of social behavior. Our overlapping circuit map therefore helps to delineate the circuits involved in the various domains of social behavior and to identify gaps in knowledge.
Collapse
Affiliation(s)
- Ziwen Wang
- Department of Psychiatry, Columbia University; New York State Psychiatric Institute, New York, New York, USA
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, Maryland, USA
| | - Hannah Yueh
- Department of Psychiatry, Columbia University; New York State Psychiatric Institute, New York, New York, USA
| | - Mirabella Chau
- Department of Psychiatry, Columbia University; New York State Psychiatric Institute, New York, New York, USA
| | - Jeremy Veenstra-VanderWeele
- Department of Psychiatry, Columbia University; New York State Psychiatric Institute, New York, New York, USA
| | - Kally C O'Reilly
- Department of Psychiatry, Columbia University; New York State Psychiatric Institute, New York, New York, USA
| |
Collapse
|
2
|
Serotonin 5-HT 1B receptors mediate the antidepressant- and anxiolytic-like effects of ventromedial prefrontal cortex deep brain stimulation in a mouse model of social defeat. Psychopharmacology (Berl) 2022; 239:3875-3892. [PMID: 36282287 DOI: 10.1007/s00213-022-06259-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 09/28/2022] [Indexed: 10/31/2022]
Abstract
BACKGROUND Deep brain stimulation (DBS) delivered to the ventromedial prefrontal cortex (vmPFC) induces antidepressant- and anxiolytic-like responses in various animal models. Electrophysiology and neurochemical studies suggest that these effects may be dependent, at least in part, on the serotonergic system. In rodents, vmPFC DBS reduces raphe cell firing and increases serotonin (5-HT) release and the expression of serotonergic receptors in different brain regions. METHODS We examined whether the behavioural responses of chronic vmPFC DBS are mediated by 5-HT1A or 5-HT1B receptors through a series of experiments. First, we delivered stimulation to mice undergoing chronic social defeat stress (CSDS), followed by a battery of behavioural tests. Second, we measured the expression of 5-HT1A and 5-HT1B receptors in different brain regions with western blot. Finally, we conducted pharmacological experiments to mitigate the behavioural effects of DBS using the 5-HT1A antagonist, WAY-100635, or the 5-HT1B antagonist, GR-127935. RESULTS We found that chronic DBS delivered to stressed animals reduced the latency to feed in the novelty suppressed feeding test (NSF) and immobility in the forced swim test (FST). Though no significant changes were observed in receptor expression, 5-HT1B levels in DBS-treated animals were found to be non-significantly increased in the vmPFC, hippocampus, and nucleus accumbens and reduced in the raphe compared to non-stimulated controls. Finally, while animals given vmPFC stimulation along with WAY-100635 still presented significant responses in the NSF and FST, these were mitigated following GR-127935 administration. CONCLUSIONS The antidepressant- and anxiolytic-like effects of DBS in rodents may be partially mediated by 5-HT1B receptors.
Collapse
|
3
|
Yu XD, Zhu Y, Sun QX, Deng F, Wan J, Zheng D, Gong W, Xie SZ, Shen CJ, Fu JY, Huang H, Lai HY, Jin J, Li Y, Li XM. Distinct serotonergic pathways to the amygdala underlie separate behavioral features of anxiety. Nat Neurosci 2022; 25:1651-1663. [PMID: 36446933 DOI: 10.1038/s41593-022-01200-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 10/12/2022] [Indexed: 11/30/2022]
Abstract
Anxiety-like behaviors in mice include social avoidance and avoidance of bright spaces. Whether these features are distinctly regulated is unclear. We demonstrate that in mice, social and anxiogenic stimuli, respectively, increase and decrease serotonin (5-HT) levels in basal amygdala (BA). In dorsal raphe nucleus (DRN), 5-HT∩vGluT3 neurons projecting to BA parvalbumin (DRN5-HT∩vGluT3-BAPV) and pyramidal (DRN5-HT∩vGluT3-BAPyr) neurons have distinct intrinsic properties and gene expression and respond to anxiogenic and social stimuli, respectively. Activation of DRN5-HT∩vGluT3→BAPV inhibits 5-HT release via GABAB receptors on serotonergic terminals in BA, inducing social avoidance and avoidance of bright spaces. Activation of DRN5-HT∩vGluT3→BA neurons inhibits two subsets of BAPyr neurons via 5-HT1A receptors (HTR1A) and 5-HT1B receptors (HTR1B). Pharmacological inhibition of HTR1A and HTR1B in BA induces avoidance of bright spaces and social avoidance, respectively. These findings highlight the functional significance of heterogenic inputs from DRN to BA subpopulations in the regulation of separate anxiety-related behaviors.
Collapse
Affiliation(s)
- Xiao-Dan Yu
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Center of Brain Science and Brain-machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China.,Department of Neurology of the Second Affiliated Hospital, Interdisciplinary Institute of Neuroscience and Technology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China
| | - Yi Zhu
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Center of Brain Science and Brain-machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Qi-Xin Sun
- NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Center of Brain Science and Brain-machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Fei Deng
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China
| | - Jinxia Wan
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China
| | - Di Zheng
- NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Center of Brain Science and Brain-machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Wankun Gong
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shi-Ze Xie
- NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Center of Brain Science and Brain-machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Chen-Jie Shen
- NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Center of Brain Science and Brain-machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Jia-Yu Fu
- NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Center of Brain Science and Brain-machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Huiqian Huang
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Hsin-Yi Lai
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Department of Neurology of the Second Affiliated Hospital, Interdisciplinary Institute of Neuroscience and Technology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, China.,College of Biomedical Engineering and Instrument Science, Key Laboratory for Biomedical Engineering of Ministry of Education, Zhejiang University, Hangzhou, China.,Affiliated Mental Health Center & Hangzhou Seventh People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Jin Jin
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology, Life Sciences Institute, Zhejiang University, Hangzhou, China
| | - Yulong Li
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China
| | - Xiao-Ming Li
- Department of Neurobiology and Department of Neurology of Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China. .,NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Center of Brain Science and Brain-machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China. .,Center for Brain Science and Brain-Inspired Intelligence, Research Units for Emotion and Emotion Disorders, Chinese Academy of Medical Sciences/Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangzhou, China.
| |
Collapse
|
4
|
Liu XJ, Wang HJ, Wang XY, Ning YX, Gao J. GABABR1 in DRN mediated GABA to regulate 5-HT expression in multiple brain regions in male rats with high and low aggressive behavior. Neurochem Int 2021; 150:105180. [PMID: 34509561 DOI: 10.1016/j.neuint.2021.105180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 08/26/2021] [Accepted: 09/06/2021] [Indexed: 11/21/2022]
Abstract
The identity of the mechanism that controls aggressive behavior in rodents is unclear. Serotonin (5-HT) and GABA are associated with aggressive behavior in rodents. However, the regulatory relationship between these chemicals in the different brain regions of rats has not been fully defined. This study aimed to clarify the role of GABABR1 in DRN-mediated GABA to regulate 5-HT expression in multiple brain regions in male rats with high and low aggressive behavior. Rat models of highly and less aggressive behavior were established through social isolation plus resident intruder. On this basis, GABA content in the DRN and 5-HT contents in the PFC, hypothalamus, hippocampus and DRN were detected using ELISA. Co-expression of 5-HT and GB1 in the DRN was detected by immunofluorescence and immunoelectron microscopy at the tissue and subcellular levels, respectively. GB1-specific agonist baclofen and GB1-specific inhibitor CGP35348 were injected into the DRN by stereotaxic injection. Changes in 5-HT levels in the PFC, hypothalamus and hippocampus were detected afterward. After modeling, rats with highly aggressive behavior exhibited higher aggressive behavior scores, shorter latencies of aggression, and higher total distances in the open field test than rats with less aggressive behavior. The contents of 5-HT in the PFC, hypothalamus and hippocampus of rats with high and low aggressive behavior (no difference between the two groups) were significantly decreased, but the change in GABA content in the DRN was the opposite. GB1 granules could be found on synaptic membranes containing 5-HT granules, which indicated that 5-HT neurons in the DRN co-expressed with GB1, which also occurred in double immunofluorescence results. At the same time, we found that the expression of GB1 in the DRN of rats with high and low aggressive behavior was significantly increased, and the expression of GB1 in the DRN of rats with low aggressive behavior was significantly higher than that in rats with high aggressive behavior. Nevertheless, the expression of 5-HT in DRN was opposite in these two groups. After microinjection of baclofen into the DRN, the 5-HT contents in the PFC, hypothalamus and hippocampus of rats in each group decreased significantly. In contrast, the 5-HT contents in the PFC, hypothalamus and hippocampus of rats in each group increased significantly after injection with CGP35348. The significant increase in GABA in the DRN combined with the significant increase in GB1 in the DRN further mediated the synaptic inhibition effect, which reduced the 5-HT level of 5-HT neurons in the DRN, resulting in a significant decrease in 5-HT levels in the PFC, hypothalamus and hippocampus. Therefore, GB1-mediated GABA regulation of 5-HT levels in the PFC, hypothalamus and hippocampus is one of the mechanisms of highly and less aggressive behavior originating in the DRN. The increased GB1 level in the DRN of LA-behavior rats exhibited a greater degree of change than in the HA-group rats, which indicated that differently decreased 5-HT levels in the DRN may be the internal mechanisms of high and low aggression behaviors.
Collapse
Affiliation(s)
- Xiao-Ju Liu
- Shandong University of Traditional Chinese Medicine, Jinan, 250355, People's Republic of China
| | - Hai-Juan Wang
- Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, 250117, People's Republic of China
| | - Xiao-Yu Wang
- Shandong University of Traditional Chinese Medicine, Jinan, 250355, People's Republic of China
| | - Yin-Xia Ning
- Shandong University of Traditional Chinese Medicine, Jinan, 250355, People's Republic of China
| | - Jie Gao
- Shandong University of Traditional Chinese Medicine, Jinan, 250355, People's Republic of China.
| |
Collapse
|
5
|
Takakura AC, Malheiros-Lima MR, Moreira TS. Excitatory and inhibitory modulation of parafacial respiratory neurons in the control of active expiration. Respir Physiol Neurobiol 2021; 289:103657. [PMID: 33781931 DOI: 10.1016/j.resp.2021.103657] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 02/22/2021] [Accepted: 03/21/2021] [Indexed: 01/21/2023]
Abstract
In order to increase ventilation, the respiratory system engages active expiration through recruitment of abdominal muscles. Here, we reviewed the new advances in the modulation of parafacial respiratory (pF) region to trigger active expiration. In addition, we also made a comprehensive discussion of experiments indicating that the lateral aspect of the pF (pFL) is anatomically and functionally distinct from the adjacent and partially overlapping chemosensitive neurons of the ventral aspect of the pF (pFV) also named the retrotrapezoid nucleus. Recent evidence suggest a complex network responsible for the generation of active expiration and neuromodulatory systems that influence its activity. The activity of the pFL is tonically inhibited by inhibitory inputs and also receives excitatory inputs from chemoreceptors (central x peripheral) as well as from catecholaminergic C1 neurons. Therefore, the modulatory inputs and the physiological conditions under which these mechanisms are used to recruit active expiration and increase ventilation need further investigation.
Collapse
Affiliation(s)
- Ana C Takakura
- Department of Pharmacology, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, 05508-000, São Paulo, SP, Brazil.
| | - Milene R Malheiros-Lima
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, 05508-000, São Paulo, SP, Brazil
| | - Thiago S Moreira
- Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, 05508-000, São Paulo, SP, Brazil.
| |
Collapse
|
6
|
Silva JDN, Oliveira LM, Souza FC, Moreira TS, Takakura AC. GABAergic neurons of the medullary raphe regulate active expiration during hypercapnia. J Neurophysiol 2020; 123:1933-1943. [PMID: 32267190 DOI: 10.1152/jn.00698.2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The parafacial respiratory group (pFRG), located in the lateral aspect of the rostroventral lateral medulla, has been described as a conditional expiratory oscillator that emerges mainly in conditions of high metabolic challenges to increase breathing. The convergence of inhibitory and excitatory inputs to pFRG and the generation of active expiration may be more complex than previously thought. We hypothesized that the medullary raphe, a region that has long been described to be involved in breathing activity, is also responsible for the expiratory activity under hypercapnic condition. To test this hypothesis, we performed anatomical and physiological experiments in urethane-anesthetized adult male Wistar rats. Our data showed anatomical projections from serotonergic (5-HT-ergic) and GABAergic neurons of raphe magnus (RMg) and obscurus (ROb) to the pFRG region. Pharmacological inhibition of RMg or ROb with muscimol (60 pmol/30 nL) did not change the frequency or amplitude of diaphragm activity and did not generate active expiration. However, under hypercapnia (9-10% CO2), the inhibition of RMg or ROb increased the amplitude of abdominal activity, without changing the increased amplitude of diaphragm activity. Depletion of serotonergic neurons with saporin anti-SERT injections into ROb and RMg did not increase the amplitude of abdominal activity during hypercapnia. These results show that the presumably GABAergic neurons within the RMg and ROb may be the inhibitory source to modulate the activity of pFRG during hypercapnia condition.NEW & NOTEWORTHY Medullary raphe has been involved in the inspiratory response to central chemoreflex; however, these reports have never addressed the role of raphe neurons on active expiration induced by hypercapnia. Here, we showed that a subset of GABA cells within the medullary raphe directly project to the parafacial respiratory region, modulating active expiration under high levels of CO2.
Collapse
Affiliation(s)
- Josiane do N Silva
- Departamento de Farmacologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, São Paulo, Brazil
| | - Luiz M Oliveira
- Departamento de Farmacologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, São Paulo, Brazil
| | - Felipe C Souza
- Departamento de Farmacologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, São Paulo, Brazil
| | - Thiago S Moreira
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biomedicas, Universidade de São Paulo, São Paulo, Brazil
| | - Ana C Takakura
- Departamento de Farmacologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, São Paulo, Brazil
| |
Collapse
|
7
|
Passos ADCF, Herculano AM, Oliveira KRHM, de Lima SMA, Rocha FAF, Freitas HR, da Silva Sampaio L, Figueiredo DP, da Costa Calaza K, de Melo Reis RA, do Nascimento JLM. Regulation of the Serotonergic System by Kainate in the Avian Retina. Cell Mol Neurobiol 2019; 39:1039-1049. [PMID: 31197744 DOI: 10.1007/s10571-019-00701-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 06/07/2019] [Indexed: 12/20/2022]
Abstract
Serotonin (5-HT) has been recognized as a neurotransmitter in the vertebrate retina, restricted mainly to amacrine and bipolar cells. It is involved with synaptic processing and possibly as a mitogenic factor. We confirm that chick retina amacrine and bipolar cells are, respectively, heavily and faintly immunolabeled for 5-HT. Amacrine serotonergic cells also co-express tyrosine hydroxylase (TH), a marker of dopaminergic cells in the retina. Previous reports demonstrated that serotonin transport can be modulated by neurotransmitter receptor activation. As 5-HT is diffusely released as a neuromodulator and co-localized with other transmitters, we evaluated if 5-HT uptake or release is modulated by several mediators in the avian retina. The role of different glutamate receptors on serotonin transport and release in vitro and in vivo was also studied. We show that L-glutamate induces an inhibitory effect on [3H]5-HT uptake and this effect was specific to kainate receptor activation. Kainate-induced decrease in [3H]5-HT uptake was blocked by CNQX, an AMPA/kainate receptor antagonist, but not by MK-801, a NMDA receptor antagonist. [3H]5-HT uptake was not observed in the presence of AMPA, thus suggesting that the decrease in serotonin uptake is mediated by kainate. 5-HT (10-50 μM) had no intrinsic activity in raising intracellular Ca2+, but addition of 10 μM 5-HT decreased Ca2+ shifts induced by KCl in retinal neurons. Moreover, kainate decreased the number of bipolar and amacrine cells labeled to serotonin in chick retina. In conclusion, our data suggest a highly selective effect of kainate receptors in the regulation of serotonin functions in the retinal cells.
Collapse
Affiliation(s)
- Adelaide da Conceição Fonseca Passos
- Laboratório de Neuroquímica Molecular e Celular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Campus Universitário do Guamá, Rua Augusto Correa 01, Belém-PA, 66075-110, Brazil
| | - Anderson Manoel Herculano
- Laboratório de Neuroquímica Molecular e Celular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Campus Universitário do Guamá, Rua Augusto Correa 01, Belém-PA, 66075-110, Brazil
| | - Karen R H M Oliveira
- Laboratório de Neuroquímica Molecular e Celular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Campus Universitário do Guamá, Rua Augusto Correa 01, Belém-PA, 66075-110, Brazil
| | - Silene Maria A de Lima
- Lab de Neurobiologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém-PA, Brazil
| | - Fernando A F Rocha
- Lab de Neurobiologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém-PA, Brazil
| | - Hércules Rezende Freitas
- Laboratório de Neuroquímica, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio De Janeiro-RJ, Brazil
- Escola de Ciências da Saúde, Centro Universitário IBMR, Rio De Janeiro-RJ, Brazil
| | - Luzia da Silva Sampaio
- Laboratório de Neuroquímica, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio De Janeiro-RJ, Brazil
| | - Danniel Pereira Figueiredo
- Laboratório de Neuroquímica, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio De Janeiro-RJ, Brazil
| | - Karin da Costa Calaza
- Lab Neurobiologia da Retina, Programa de Pós-graduação em Neurociências, Universidade Federal Fluminense, Rio De Janeiro-RJ, Brazil
| | - Ricardo Augusto de Melo Reis
- Laboratório de Neuroquímica, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio De Janeiro-RJ, Brazil
| | - José Luiz Martins do Nascimento
- Laboratório de Neuroquímica Molecular e Celular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Campus Universitário do Guamá, Rua Augusto Correa 01, Belém-PA, 66075-110, Brazil.
| |
Collapse
|
8
|
Cathala A, Devroye C, Drutel G, Revest JM, Artigas F, Spampinato U. Serotonin 2B receptors in the rat dorsal raphe nucleus exert a GABA-mediated tonic inhibitory control on serotonin neurons. Exp Neurol 2018; 311:57-66. [PMID: 30257183 DOI: 10.1016/j.expneurol.2018.09.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 09/10/2018] [Accepted: 09/22/2018] [Indexed: 11/30/2022]
Abstract
The central serotonin2B receptor (5-HT2BR) is a well-established modulator of dopamine (DA) neuron activity in the rodent brain. Recent studies in rats have shown that the effect of 5-HT2BR antagonists on accumbal and medial prefrontal cortex (mPFC) DA outflow results from a primary action in the dorsal raphe nucleus (DRN), where they activate 5-HT neurons innervating the mPFC. Although the mechanisms underlying this interaction remain largely unknown, data in the literature suggest the involvement of DRN GABAergic interneurons in the control of 5-HT activity. The present study examined this hypothesis using in vivo (intracerebral microdialysis) and in vitro (immunohistochemistry coupled to reverse transcription-polymerase chain reaction) experimental approaches in rats. Intraperitoneal (0.16 mg/kg) or intra-DRN (1 μM) administration of the selective 5-HT2BR antagonist RS 127445 increased 5-HT outflow in both the DRN and the mPFC, these effects being prevented by the intra-DRN perfusion of the GABAA antagonist bicuculline (100 μM), as well as by the subcutaneous (0.16 mg/kg) or the intra-DRN (0.1 μM) administration of the selective 5-HT1AR antagonist WAY 100635. The increase in DRN 5-HT outflow induced by the intra-DRN administration of the selective 5-HT reuptake inhibitor citalopram (0.1 μM) was potentiated by the intra-DRN administration (0.5 μM) of RS 127445 only in the absence of bicuculline perfusion. Finally, in vitro experiments revealed the presence of the 5-HT2BR mRNA on DRN GABAergic interneurons. Altogether, these results show that, in the rat DRN, 5-HT2BRs are located on GABAergic interneurons, and exert a tonic inhibitory control on 5-HT neurons innervating the mPFC.
Collapse
Affiliation(s)
- Adeline Cathala
- Inserm U1215, Neurocentre Magendie, Physiopathology and therapeutic approaches of stress-related diseases, Bordeaux F-33000, France; Université de Bordeaux, Bordeaux F-33000, France.
| | - Céline Devroye
- Inserm U1215, Neurocentre Magendie, Physiopathology and therapeutic approaches of stress-related diseases, Bordeaux F-33000, France; Université de Bordeaux, Bordeaux F-33000, France.
| | - Guillaume Drutel
- Inserm U1215, Neurocentre Magendie, Physiopathology and therapeutic approaches of stress-related diseases, Bordeaux F-33000, France; Université de Bordeaux, Bordeaux F-33000, France.
| | - Jean-Michel Revest
- Inserm U1215, Neurocentre Magendie, Physiopathology and therapeutic approaches of stress-related diseases, Bordeaux F-33000, France; Université de Bordeaux, Bordeaux F-33000, France.
| | - Francesc Artigas
- Department of Neurochemistry and Neuropharmacology, Institut d'Investigacions Biomèdiques de Barcelona, CSIC-IDIBAPS, Rosselló 161, 08036 Barcelona, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain.
| | - Umberto Spampinato
- Inserm U1215, Neurocentre Magendie, Physiopathology and therapeutic approaches of stress-related diseases, Bordeaux F-33000, France; Université de Bordeaux, Bordeaux F-33000, France.
| |
Collapse
|
9
|
Jacobson LH, Vlachou S, Slattery DA, Li X, Cryan JF. The Gamma-Aminobutyric Acid B Receptor in Depression and Reward. Biol Psychiatry 2018; 83:963-976. [PMID: 29759132 DOI: 10.1016/j.biopsych.2018.02.006] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2017] [Revised: 01/14/2018] [Accepted: 02/06/2018] [Indexed: 12/31/2022]
Abstract
The metabotropic gamma-aminobutyric acid B (GABAB) receptor was the first described obligate G protein-coupled receptor heterodimer and continues to set the stage for discoveries in G protein-coupled receptor signaling complexity. In this review, dedicated to the life and work of Athina Markou, we explore the role of GABAB receptors in depression, reward, and the convergence of these domains in anhedonia, a shared symptom of major depressive disorder and withdrawal from drugs of abuse. GABAB receptor expression and function are enhanced by antidepressants and reduced in animal models of depression. Generally, GABAB receptor antagonists are antidepressant-like and agonists are pro-depressive. Exceptions to this rule likely reflect the differential influence of GABAB1 isoforms in depression-related behavior and neurobiology, including the anhedonic effects of social stress. A wealth of data implicate GABAB receptors in the rewarding effects of drugs of abuse. We focus on nicotine as an example. GABAB receptor activation attenuates, and deactivation enhances, nicotine reward and associated neurobiological changes. In nicotine withdrawal, however, GABAB receptor agonists, antagonists, and positive allosteric modulators enhance anhedonia, perhaps owing to differential effects of GABAB1 isoforms on the dopaminergic system. Nicotine cue-induced reinstatement is more reliably attenuated by GABAB receptor activation. Separation of desirable and undesirable side effects of agonists is achievable with positive allosteric modulators, which are poised to enter clinical studies for drug abuse. GABAB1 isoforms are key to understanding the neurobiology of anhedonia, whereas allosteric modulators may offer a mechanism for targeting specific brain regions and processes associated with reward and depression.
Collapse
Affiliation(s)
- Laura H Jacobson
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Victoria, Australia; Department of Pharmacology and Therapeutics, University of Melbourne, Victoria, Australia.
| | - Styliani Vlachou
- School of Nursing and Human Sciences, Faculty of Science and Health, Dublin City University, Glasnevin, Dublin
| | - David A Slattery
- Klinik für Psychiatrie, Psychosomatik und Psychotherapie, Universitätsklinikum Frankfurt, Frankfurt am Main, Germany
| | - Xia Li
- Department of Psychiatry, School of Medicine, University of California San Diego, La Jolla, California
| | - John F Cryan
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland
| |
Collapse
|
10
|
de Beaurepaire R. A Review of the Potential Mechanisms of Action of Baclofen in Alcohol Use Disorder. Front Psychiatry 2018; 9:506. [PMID: 30459646 PMCID: PMC6232933 DOI: 10.3389/fpsyt.2018.00506] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 09/25/2018] [Indexed: 12/17/2022] Open
Abstract
Baclofen, a GABA-B receptor agonist, is a promising treatment for alcohol use disorder (AUD). Its mechanism of action in this condition is unknown. GABA-B receptors interact with many biological systems potentially involved in AUD, including transduction pathways and neurotransmitter systems. Preclinical studies have shown that GABA-B receptors are involved in memory storage and retrieval, reward, motivation, mood and anxiety; neuroimaging studies in humans show that baclofen produces region-specific alterations in cerebral activity; GABA-B receptor activation may have neuroprotective effects; baclofen also has anti-inflammatory properties that may be of interest in the context of addiction. However, none of these biological effects fully explain the mechanism of action of baclofen in AUD. Data from clinical studies have provided a certain number of elements which may be useful for the comprehension of its mechanism of action: baclofen typically induces a state of indifference toward alcohol; the effective dose of baclofen in AUD is extremely variable from one patient to another; higher treatment doses correlate with the severity of the addiction; many of the side effects of baclofen resemble those of alcohol, raising the possibility that baclofen acts as a substitution drug; usually, however, there is no tolerance to the effects of baclofen during long-term AUD treatment. In the present article, the biological effects of baclofen are reviewed in the light of its clinical effects in AUD, assuming that, in many instances, clinical effects can be reliable indicators of underlying biological processes. In conclusion, it is proposed that baclofen may suppress the Pavlovian association between cues and rewards through an action in a critical part of the dopaminergic network (the amygdala), thereby normalizing the functional connectivity in the reward network. It is also proposed that this action of baclofen is made possible by the fact that baclofen and alcohol act on similar brain systems in certain regions of the brain.
Collapse
|
11
|
Rolland B, Simon N, Franchitto N. Safety Challenges of Using High Dose Baclofen for Alcohol Use Disorder: A Focused Review. Front Psychiatry 2018; 9:367. [PMID: 30186187 PMCID: PMC6113385 DOI: 10.3389/fpsyt.2018.00367] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 07/24/2018] [Indexed: 01/13/2023] Open
Abstract
Since the early 2000s, the gamma-aminobutyric acid type B (GABA-B) receptor agonist baclofen has been extensively used for treating alcohol use disorder (AUD). In some countries, like France, Australia, or Germany, baclofen has been used at patient-tailored dose regimens, which can reach 300 mgpd or even more in some patients. The GABA-B-related pharmacology of baclofen expose patients to a specific profile of neuropsychiatric adverse drug reactions (ADRs), primarily some frequent sedative symptoms whose risk of occurrence and severity are both related to the absolute baclofen dosing and the kinetics of dose variations. Other frequent neuropsychiatric ADRs can occur, i.e., tinnitus, insomnia, or dizziness. More rarely, other serious ADRs have been reported, like seizures, manic symptoms, or sleep apnea. However, real-life AUD patients are also exposed to other sedative drugs, like alcohol of course, but also benzodiazepines, other drugs of abuse, or other sedative medications. Consequently, the occurrence of neuropsychiatric safety issues in these patients is essentially the result of a complex multifactorial exposure, in which baclofen causality is rarely obvious by itself. As a result, the decision of initiating baclofen, as well as the daily dose management should be patient-tailored, according the medical history but also the immediate clinical situation of the patient. The overall safety profile of baclofen, as well as the clinical context in which baclofen is used, have many similarities with the use of opiate substitution medications for opiate use disorder. This empirical statement has many implications on how baclofen should be managed and dosing should be adjusted. Moreover, this constant patient-tailored adjustment can be difficult to adapt in the design of clinical trials, which may explain inconsistent findings in baclofen-related literature on AUD.
Collapse
Affiliation(s)
- Benjamin Rolland
- Service Universitaire d'Addictologie de Lyon (SUAL), Pôle MOPHA, CH Le Vinatier, Bron, France.,Univ Lyon, Inserm U1028, CNRS UMR5292, UCBL, CRNL, Lyon, France
| | - Nicolas Simon
- APHM, INSERM, IRD, SESSTIM, Hop Sainte Marguerite, Service de Pharmacologie Clinique, CAP-TV, Aix Marseille Univ, Marseille, France
| | | |
Collapse
|
12
|
Xiao J, Song M, Li F, Liu X, Anwar A, Zhao H. Effects of GABA microinjection into dorsal raphe nucleus on behavior and activity of lateral habenular neurons in mice. Exp Neurol 2017; 298:23-30. [DOI: 10.1016/j.expneurol.2017.08.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 07/28/2017] [Accepted: 08/23/2017] [Indexed: 01/23/2023]
|
13
|
Tokunaga R, Shimoju R, Shibata H, Kurosawa M. Somatosensory regulation of serotonin release in the central nucleus of the amygdala is mediated via corticotropin releasing factor and gamma-aminobutyric acid in the dorsal raphe nucleus. J Physiol Sci 2017; 67:689-698. [PMID: 27744641 PMCID: PMC10718013 DOI: 10.1007/s12576-016-0498-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 10/06/2016] [Indexed: 10/20/2022]
Abstract
Noxious cutaneous stimulation increases, whereas innocuous cutaneous stimulation decreases serotonin (5-HT) release in the central nucleus of the amygdala (CeA) in anesthetized rats. In the present study, we investigated the contribution of corticotropin releasing factor (CRF) receptors and gamma-aminobutyric acid (GABA) receptors in the dorsal raphe nucleus (DRN) to those responses. Release of 5-HT in the CeA was monitored by microdialysis before and after 10-min stimulation by pinching or stroking. Increased 5-HT release in the CeA in response to pinching was abolished by CRF2 receptor antagonism in the DRN. Decreased 5-HT release in the CeA in response to stroking was abolished by either CRF1 receptor antagonism or GABAA receptor antagonism in the DRN. These results suggest that opposite responses of 5-HT release in the CeA to noxious versus innocuous stimulation of the skin are due to separate contributions of CRF2, CRF1 and GABAA receptors in the DRN.
Collapse
Affiliation(s)
- Ryota Tokunaga
- Center for Medical Science, International University of Health and Welfare, 2600-1 Kitakanemaru, Otawara, Tochigi, 324-8501, Japan
| | - Rie Shimoju
- Division of Physical Therapy, Graduate School of Health and Welfare Sciences, International University of Health and Welfare, Otawara, Tochigi, 324-8501, Japan
| | - Hideshi Shibata
- Laboratory of Veterinary Anatomy, Institute of Agriculture, Tokyo University of Agriculture and Technology, Fuchu, Tokyo, 183-8509, Japan
| | - Mieko Kurosawa
- Center for Medical Science, International University of Health and Welfare, 2600-1 Kitakanemaru, Otawara, Tochigi, 324-8501, Japan.
- Division of Physical Therapy, Graduate School of Health and Welfare Sciences, International University of Health and Welfare, Otawara, Tochigi, 324-8501, Japan.
- Department of Pharmaceutical Sciences, International University of Health and Welfare, Otawara, Tochigi, 324-8501, Japan.
| |
Collapse
|
14
|
Neuroprotective role of GABAB receptor modulation against streptozotocin-induced behavioral and biochemical abnormalities in rats. Neuroscience 2017; 357:67-74. [DOI: 10.1016/j.neuroscience.2017.05.054] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Revised: 05/22/2017] [Accepted: 05/30/2017] [Indexed: 11/18/2022]
|
15
|
Jacobson LH, Hoyer D, Fehlmann D, Bettler B, Kaupmann K, Cryan JF. Blunted 5-HT 1A receptor-mediated responses and antidepressant-like behavior in mice lacking the GABA B1a but not GABA B1b subunit isoforms. Psychopharmacology (Berl) 2017; 234:1511-1523. [PMID: 28070618 DOI: 10.1007/s00213-016-4521-5] [Citation(s) in RCA: 9] [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: 10/02/2016] [Accepted: 12/19/2016] [Indexed: 12/13/2022]
Abstract
RATIONALE There is accumulating evidence for a role of GABAB receptors in depression. GABAB receptors are heterodimers of GABAB1 and GABAB2 receptor subunits. The predominant GABAB1 subunit isoforms are GABAB1a and GABAB1b. GABAB1 isoforms in mice differentially influence cognition, conditioned fear, and susceptibility to stress, yet their influence in tests of antidepressant-like activity has not been fully investigated. OBJECTIVES Given the interactions between GABAB receptors and the serotonergic system and the involvement of 5-HT1A receptors (5-HT1AR) in antidepressant action, we sought to evaluate 5-HT1AR function in GABAB1a-/- and GABAB1b-/- mice. METHODS GABAB1a-/- and GABAB1b-/- mice were assessed in the forced swim test (FST), and body temperature and hypothalamic-pituitary-adrenal (HPA) responses to the 5-HT1AR agonist 8-OH-DPAT were determined. Brain 5-HT1AR expression was assessed by [3H]-MPPF and [3H]-8-OH-DPAT autoradiography and 5-HT1AR G-protein coupling by [35S]GTP-γ-S autoradiography. RESULTS As previously described, GABAB1a-/- mice showed an antidepressant-like profile in the FST. GABAB1a-/- mice also demonstrated profoundly blunted hypothermic and motoric responses to 8-OH-DPAT. Furthermore, 8-OH-DPAT-induced corticosterone and adrenocorticotropic hormone (ACTH) release were both attenuated in GABAB1a-/- mice. Interestingly, [3H]-MPPF and [3H]-8-OH-DPAT binding was largely unaffected by genotype. [35S]GTP-γ-S autoradiography suggested that altered 5-HT1AR G-protein coupling only partially contributes to the functional presynaptic 5-HT1AR desensitization, and not at all to the blunted postsynaptic 5-HT1AR-mediated responses, seen in GABAB1a-/- mice. CONCLUSION These data demonstrate distinct functional links between 5-HT1ARs and the GABAB1a subunit isoform and suggest that the GABAB1a isoform may be implicated in the antidepressant-like effects of GABAB receptor antagonists and in neurobiological mechanisms underlying depression.
Collapse
Affiliation(s)
- Laura H Jacobson
- Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3052, Australia.
- Department of Pharmacology and Therapeutics, University of Melbourne, Parkville, VIC, 3052, Australia.
| | - Daniel Hoyer
- Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3052, Australia
- Department of Pharmacology and Therapeutics, University of Melbourne, Parkville, VIC, 3052, Australia
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Dominique Fehlmann
- Autoimmunity, Transplantation and Inflammation, Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4002, Basel, Switzerland
| | - Bernhard Bettler
- Department of Biomedicine, Pharmazentrum, University of Basel, CH-4056, Basel, Switzerland
| | - Klemens Kaupmann
- Autoimmunity, Transplantation and Inflammation, Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4002, Basel, Switzerland
| | - John F Cryan
- APC Microbiome Institute, University College Cork, Cork, Ireland.
- Department of Anatomy and Neuroscience, University College Cork, Western Gateway Building, Cork, Ireland.
| |
Collapse
|
16
|
Involvement of 5-HT 3 receptors in the action of vortioxetine in rat brain: Focus on glutamatergic and GABAergic neurotransmission. Neuropharmacology 2016; 108:73-81. [DOI: 10.1016/j.neuropharm.2016.04.023] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 04/18/2016] [Accepted: 04/18/2016] [Indexed: 01/03/2023]
|
17
|
The influence of electrical stimulation on dorsal raphe nucleus with different current intensities on morphine-induced conditioned place preference in male rats. Pharmacol Rep 2015; 67:832-6. [DOI: 10.1016/j.pharep.2015.01.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Revised: 01/12/2015] [Accepted: 01/13/2015] [Indexed: 01/23/2023]
|
18
|
Luo M, Zhou J, Liu Z. Reward processing by the dorsal raphe nucleus: 5-HT and beyond. ACTA ACUST UNITED AC 2015; 22:452-60. [PMID: 26286655 PMCID: PMC4561406 DOI: 10.1101/lm.037317.114] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 07/06/2015] [Indexed: 12/20/2022]
Abstract
The dorsal raphe nucleus (DRN) represents one of the most sensitive reward sites in the brain. However, the exact relationship between DRN neuronal activity and reward signaling has been elusive. In this review, we will summarize anatomical, pharmacological, optogenetics, and electrophysiological studies on the functions and circuit mechanisms of DRN neurons in reward processing. The DRN is commonly associated with serotonin (5-hydroxytryptamine; 5-HT), but this nucleus also contains neurons of the neurotransmitter phenotypes of glutamate, GABA and dopamine. Pharmacological studies indicate that 5-HT might be involved in modulating reward- or punishment-related behaviors. Recent optogenetic stimulations demonstrate that transient activation of DRN neurons produces strong reinforcement signals that are carried out primarily by glutamate. Moreover, activation of DRN 5-HT neurons enhances reward waiting. Electrophysiological recordings reveal that the activity of DRN neurons exhibits diverse behavioral correlates in reward-related tasks. Studies so far thus demonstrate the strong power of DRN neurons in reward signaling and at the same time invite additional efforts to dissect the roles and mechanisms of different DRN neuron types in various processes of reward-related behaviors.
Collapse
Affiliation(s)
- Minmin Luo
- National Institute of Biological Sciences, Beijing 102206, China School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Jingfeng Zhou
- National Institute of Biological Sciences, Beijing 102206, China
| | - Zhixiang Liu
- National Institute of Biological Sciences, Beijing 102206, China
| |
Collapse
|
19
|
Glutamate input in the dorsal raphe nucleus as a determinant of escalated aggression in male mice. J Neurosci 2015; 35:6452-63. [PMID: 25904796 DOI: 10.1523/jneurosci.2450-14.2015] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Although the dorsal raphe nucleus (DRN) has long been linked to neural control of aggression, little is known about the regulatory influences of the DRN when an animal engages in either adaptive species-typical aggressive behavior or escalated aggression. Therefore it is important to explore which neurotransmitter inputs into the DRN determine the escalation of aggression in male mice. Previously, we observed that microinjection of the GABAB receptor agonist baclofen into the DRN escalates aggressive behavior in male mice. Here, we used a serotonin (5-HT) neuron-specific GABAB receptor knock-out mouse to demonstrate that baclofen acts on nonserotonergic neurons to escalate aggression. Intra-DRN baclofen administration increased glutamate release, but did not alter GABA release, within the DRN. Microinjection of l-glutamate into the DRN escalated dose-dependently attack bites toward an intruder. In vivo microdialysis showed that glutamate release increased in the DRN during an aggressive encounter, and the level of glutamate was further increased when the animal was engaged in escalated aggressive behavior after social instigation. Finally, 5-HT release was increased within the DRN and also in the medial prefrontal cortex when animals were provoked by social instigation, and during escalated aggression after social instigation, but this increase in 5-HT release was not observed when animals were engaged in species-typical aggression. In summary, glutamate input into the DRN is enhanced during escalated aggression, which causes a phasic increase of 5-HT release from the DRN 5-HT neurons.
Collapse
|
20
|
Haduch A, Bromek E, Kot M, Kamińska K, Gołembiowska K, Daniel WA. The cytochrome P450 2D-mediated formation of serotonin from 5-methoxytryptamine in the brain in vivo
: a microdialysis study. J Neurochem 2015; 133:83-92. [DOI: 10.1111/jnc.13031] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 12/26/2014] [Indexed: 01/14/2023]
Affiliation(s)
- Anna Haduch
- Institute of Pharmacology; Polish Academy of Sciences; Kraków Poland
| | - Ewa Bromek
- Institute of Pharmacology; Polish Academy of Sciences; Kraków Poland
| | - Marta Kot
- Institute of Pharmacology; Polish Academy of Sciences; Kraków Poland
| | | | | | | |
Collapse
|
21
|
The modulatory action of harmane on serotonergic neurotransmission in rat brain. Brain Res 2015; 1597:57-64. [DOI: 10.1016/j.brainres.2014.11.056] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 10/27/2014] [Accepted: 11/27/2014] [Indexed: 02/06/2023]
|
22
|
Martin CBP, Gassmann M, Chevarin C, Hamon M, Rudolph U, Bettler B, Lanfumey L, Mongeau R. Effect of genetic and pharmacological blockade of GABA receptors on the 5-HT2C receptor function during stress. J Neurochem 2014; 131:566-72. [PMID: 25113583 DOI: 10.1111/jnc.12929] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 07/27/2014] [Accepted: 08/08/2014] [Indexed: 11/28/2022]
Abstract
Serotonin (5-HT)2C receptors play a role in psychoaffective disorders and often contribute to the antidepressant and anxiolytic effects of psychotropic drugs. During stress, activation of these receptors exerts a negative feedback on 5-HT release, probably by increasing the activity of GABAergic interneurons. However, to date, the GABA receptor types that mediate the 5-HT2C receptor-induced feedback inhibition are still unknown. To address this question, we assessed the inhibition of 5-HT turnover by a 5-HT2C receptor agonist (RO 60-0175) at the hippocampal level and under conditions of stress, after pharmacological or genetic inactivation of either GABA-A or GABA-B receptors in mice. Neither the GABA-B receptor antagonist phaclofen nor the specific genetic ablation of either GABA-B1a or GABA-B1b subunits altered the inhibitory effect of RO 60-0175, although 5-HT turnover was markedly decreased in GABA-B1a knock-out mice in both basal and stress conditions. In contrast, the 5-HT2C receptor-mediated inhibition of 5-HT turnover was reduced by the GABA-A receptor antagonist bicuculline. However, a significant effect of 5-HT2C receptor activation persisted in mutant mice deficient in the α3 subunit of GABA-A receptors. It can be inferred that non-α3 subunit-containing GABA-A receptors, but not GABA-B receptors, mediate the 5-HT2C -induced inhibition of stress-induced increase in hippocampal 5-HT turnover in mice.
Collapse
Affiliation(s)
- Cédric B P Martin
- Paris Descartes, University of Paris, Paris, France; UPMC, University of Paris, Paris, France; Inserm UMR S894, Centre de Psychiatrie et Neurosciences, Paris, France
| | | | | | | | | | | | | | | |
Collapse
|
23
|
Iceman KE, Corcoran AE, Taylor BE, Harris MB. CO2-inhibited neurons in the medullary raphé are GABAergic. Respir Physiol Neurobiol 2014; 203:28-34. [PMID: 25087734 DOI: 10.1016/j.resp.2014.07.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2014] [Revised: 07/24/2014] [Accepted: 07/24/2014] [Indexed: 11/28/2022]
Abstract
Previous studies have reported subsets of medullary raphé neurons that are either stimulated or inhibited by CO2/pH in vitro, in situ, and in vivo. We tested the hypothesis that medullary raphé CO2-inhibited neurons are GABAergic. Extracellular recordings in unanesthetized juvenile in situ rat preparations showed reversible hypercapnia-induced suppression of 19% (63/323) of medullary raphé neurons, and this suppression persisted after antagonism of NMDA, AMPA/kainate, and GABAA receptors. We stained a subset of CO2-inhibited cells and found that most (11/12) had glutamic acid decarboxylase 67 immunoreactivity (GAD67-ir). These data indicate that the majority of acidosis-inhibited medullary raphé neurons are GABAergic, and that their chemosensitivity is independent of major fast synaptic inputs. Thus, CO2-sensitive GABAergic neurons may play a role in central CO2/pH chemoreception.
Collapse
Affiliation(s)
- Kimberly E Iceman
- Institute of Arctic Biology and Department of Biology and Wildlife, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
| | - Andrea E Corcoran
- Institute of Arctic Biology and Department of Biology and Wildlife, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
| | - Barbara E Taylor
- Institute of Arctic Biology and Department of Biology and Wildlife, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
| | - Michael B Harris
- Institute of Arctic Biology and Department of Biology and Wildlife, University of Alaska Fairbanks, Fairbanks, AK 99775, USA.
| |
Collapse
|
24
|
Ferreira MD, Menescal-de-Oliveira L. Nociceptive vocalization response in guinea pigs modulated by opioidergic, GABAergic and serotonergic neurotransmission in the dorsal raphe nucleus. Brain Res Bull 2014; 106:21-9. [DOI: 10.1016/j.brainresbull.2014.05.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Revised: 05/02/2014] [Accepted: 05/03/2014] [Indexed: 12/01/2022]
|
25
|
El zahaf NA, Elhwuegi AS. The effect of GABAmimetics on the duration of immobility in the forced swim test in albino mice. Libyan J Med 2014; 9:23480. [PMID: 24560379 PMCID: PMC3929996 DOI: 10.3402/ljm.v9.23480] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2013] [Revised: 01/21/2014] [Accepted: 01/21/2014] [Indexed: 11/23/2022] Open
Abstract
OBJECTIVES Studies regarding the role of gamma aminobutyric acid (GABA) in depression are conflicting. Therefore, it was decided to examine the effect of different drugs that enhance the GABA system on the time of immobility induced by the forced swim test (FST). MATERIALS AND METHODS Adult albino mice were divided into several groups of six animals. Each group received an intraperitoneal injection of either imipramine (10, 20, or 30 mg/kg), diazepam (0.5, 1, or 2 mg/kg), vigabatrin (100, 200, or 300 mg/kg), zolpidem (2.5, 5, or 10 mg/kg), or alprazolam (1, 2.5, or 5 mg/kg). Control groups received the appropriate vehicle. One hour after injection, the duration of immobility was measured for 5 min in the FST. The percentage change in the duration of immobility from the control was calculated for each group. The statistical test of the difference between the treated and the control groups was calculated using unpaired Student's t-test. RESULTS Imipramine produced a significant dose-dependent decrease in the duration of immobility (78, 74, and 56%, respectively). Different doses of diazepam, vigabatrin, and zolpidem produced a significant increase in the duration of immobility (119, 126, and 128%), (116, 124, and 128%), and (108, 109, and 119%), respectively. The two low doses of alprazolam produced a significant increase (115 and 120%), while the high dose produced a significant decrease in the duration of immobility (74%). CONCLUSION Increasing central GABAergic activity by different mechanisms has resulted in a depressant-like activity measured as an increase in the duration of immobility in the FST model of depression.
Collapse
Affiliation(s)
| | - Abdalla Salem Elhwuegi
- Faculty of Pharmacy, Department of Pharmacology and Clinical Pharmacy, Tripoli University Tripoli, Libya
| |
Collapse
|
26
|
|
27
|
Iceman KE, Harris MB. A group of non-serotonergic cells is CO2-stimulated in the medullary raphé. Neuroscience 2013; 259:203-13. [PMID: 24333211 DOI: 10.1016/j.neuroscience.2013.11.060] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Revised: 11/13/2013] [Accepted: 11/30/2013] [Indexed: 01/22/2023]
Abstract
Serotonin/substance P synthesizing cells in the raphé nuclei of the brain are candidates for designation as central chemoreceptors that are stimulated by CO2/pH. We have previously demonstrated that these neurons are CO2-stimulated in situ. Evidence also suggests that CO2-inhibited raphé neurons recorded in vitro and in situ synthesize GABA. Unknown is whether there are other types of chemosensitive cells in the raphé. Here, we showed that a previously unrecognized pool of raphé neurons also exhibit chemosensitivity, and that they are not serotonergic. We used extracellular recording of individual raphé neurons in the unanesthetized juvenile rat in situ perfused decerebrate brainstem preparation to assess chemosensitivity of raphé neurons. Subsequent juxtacellular labeling of individually recorded cells, and immunohistochemistry for the serotonin synthesizing enzyme tryptophan hydroxylase and for neurokinin-1 receptor (NK1R; the receptor for substance P) indicated a group of CO2-stimulated cells that are not serotonergic, but express NK1R and are closely apposed to surrounding serotonergic cells. CO2-stimulated 5-HT and non-5-HT cells constitute distinct groups that have different firing characteristics and hypercapnic sensitivities. Non-5-HT cells fire faster and are more robustly stimulated by CO2 than are 5-HT cells. Thus, we have characterized a previously unrecognized type of CO2-stimulated medullary raphé neuron that is not serotonergic, but may receive input from neighboring serotonin/substance P synthesizing chemosensitive neurons. The potential network properties of the three types of chemosensitive raphé neurons (the present non-5-HT cells, serotonergic cells, and CO2-inhibited cells) remain to be elucidated.
Collapse
Affiliation(s)
- K E Iceman
- Institute of Arctic Biology, University of Alaska, Fairbanks, AK 99775, USA; Department of Biology and Wildlife, University of Alaska, Fairbanks, AK 99775, USA.
| | - M B Harris
- Institute of Arctic Biology, University of Alaska, Fairbanks, AK 99775, USA; Department of Biology and Wildlife, University of Alaska, Fairbanks, AK 99775, USA
| |
Collapse
|
28
|
Takahashi A, Schilit AN, Kim J, DeBold JF, Koide T, Miczek KA. Behavioral characterization of escalated aggression induced by GABA(B) receptor activation in the dorsal raphe nucleus. Psychopharmacology (Berl) 2012; 224:155-66. [PMID: 22395428 PMCID: PMC3694325 DOI: 10.1007/s00213-012-2654-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Accepted: 01/26/2012] [Indexed: 01/15/2023]
Abstract
RATIONALE Pharmacological activation of GABA(B) receptors in the dorsal raphe nucleus (DRN) can escalate territorial aggression in male mice. OBJECTIVES We characterized this escalated aggression in terms of its behavioral and environmental determinants. METHODS Aggressive behavior of resident male (CFW or ICR mouse) was assessed in confrontations with a group-housed intruder. Either baclofen (0.06 nmol/0.2 μl) or vehicle (saline) was microinjected into the DRN 10 min before the confrontation. We examined baclofen-heightened aggression in five situations: aggression in a neutral arena and after social instigation (experiment 1), aggression during the light phase of the cycle (experiment 2), aggression without prior fighting experience (experiment 3), aggression toward a female (experiment 4), and aggression after defeat experiences (experiment 5). In addition, we examined the body targets towards which bites are directed and the duration of aggressive bursts after baclofen treatment. RESULTS Regardless of the past social experience, baclofen escalated aggressive behaviors. Even in the neutral arena and after defeat experiences, where aggressive behaviors were inhibited, baclofen significantly increased aggression. Baclofen increased attack bites directed at vulnerable body areas of male intruders but not toward a female and only in the dark. Also, baclofen prolonged the duration of aggressive bursts. CONCLUSIONS For baclofen to escalate aggression, specific stimulation (male intruder) and tonic level of serotonin (dark cycle) are required. Once aggressive behavior is triggered, intra-DRN baclofen escalates the level of aggression to abnormal levels and renders it difficult to terminate. Also, baclofen counteracts the effects of novelty or past experiences of defeat.
Collapse
Affiliation(s)
- Aki Takahashi
- Mouse Genomics Resource Laboratory, National Institute of Genetics (NIG), 1111 Yata, Mishima, Shizuoka 411-8540, Japan.
| | - Arielle N. Schilit
- Department of Psychology, Tufts University, Medford, Massachusetts 02155, USA
| | - Jisoo Kim
- Department of Psychology, Tufts University, Medford, Massachusetts 02155, USA
| | - Joseph F. DeBold
- Department of Psychology, Tufts University, Medford, Massachusetts 02155, USA
| | - Tsuyoshi Koide
- Mouse Genomics Resource Laboratory, National Institute of Genetics (NIG), Mishima, Shizuoka, 411-8540 Japan
| | - Klaus A. Miczek
- Department of Psychology, Tufts University, Medford, Massachusetts 02155, USA,Departments of Psychiatry, Pharmacology and Neuroscience, Tufts University School of Medicine, Boston, Massachusetts 02110, USA
| |
Collapse
|
29
|
Opioidergic, GABAergic and serotonergic neurotransmission in the dorsal raphe nucleus modulates tonic immobility in guinea pigs. Physiol Behav 2012; 106:109-16. [DOI: 10.1016/j.physbeh.2012.01.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2011] [Revised: 01/04/2012] [Accepted: 01/05/2012] [Indexed: 11/24/2022]
|
30
|
Waselus M, Valentino RJ, Van Bockstaele EJ. Collateralized dorsal raphe nucleus projections: a mechanism for the integration of diverse functions during stress. J Chem Neuroanat 2011; 41:266-80. [PMID: 21658442 PMCID: PMC3156417 DOI: 10.1016/j.jchemneu.2011.05.011] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Revised: 05/18/2011] [Accepted: 05/20/2011] [Indexed: 01/01/2023]
Abstract
The midbrain dorsal raphe nucleus (DR) is the origin of the central serotonin (5-HT) system, a key neurotransmitter system that has been implicated in the expression of normal behaviors and in diverse psychiatric disorders, particularly affective disorders such as depression and anxiety. One link between the DR-5-HT system and affective disorders is exposure to stressors. Stress is a major risk factor for affective disorders, and stressors alter activity of DR neurons in an anatomically specific manner. Stress-induced changes in DR neuronal activity are transmitted to targets of the DR via ascending serotonergic projections, many of which collateralize to innervate multiple brain regions. Indeed, the collateralization of DR efferents allows for the coordination of diverse components of the stress response. This review will summarize our current understanding of the organization of the ascending DR system and its collateral projections. Using the neuropeptide corticotropin-releasing factor (CRF) system as an example of a stress-related initiator of DR activity, we will discuss how topographic specificity of afferent regulation of ascending DR circuits serves to coordinate activity in functionally diverse target regions under appropriate conditions.
Collapse
Affiliation(s)
- Maria Waselus
- Molecular and Behavioral Neuroscience Institute, University of Michigan, Ann Arbor, MI 48109, United States.
| | | | | |
Collapse
|
31
|
Brain serotonin receptors and transporters: initiation vs. termination of escalated aggression. Psychopharmacology (Berl) 2011; 213:183-212. [PMID: 20938650 PMCID: PMC3684010 DOI: 10.1007/s00213-010-2000-y] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Accepted: 08/09/2010] [Indexed: 12/24/2022]
Abstract
RATIONALE Recent findings have shown a complexly regulated 5-HT system as it is linked to different kinds of aggression. OBJECTIVE We focus on (1) phasic and tonic changes of 5-HT and (2) state and trait of aggression, and emphasize the different receptor subtypes, their role in specific brain regions, feed-back regulation and modulation by other amines, acids and peptides. RESULTS New pharmacological tools differentiate the first three 5-HT receptor families and their modulation by GABA, glutamate and CRF. Activation of 5-HT(1A), 5-HT(1B) and 5-HT(2A/2C) receptors in mesocorticolimbic areas, reduce species-typical and other aggressive behaviors. In contrast, agonists at 5-HT(1A) and 5-HT(1B) receptors in the medial prefrontal cortex or septal area can increase aggressive behavior under specific conditions. Activation of serotonin transporters reduce mainly pathological aggression. Genetic analyses of aggressive individuals have identified several molecules that affect the 5-HT system directly (e.g., Tph2, 5-HT(1B), 5-HT transporter, Pet1, MAOA) or indirectly (e.g., Neuropeptide Y, αCaMKII, NOS, BDNF). Dysfunction in genes for MAOA escalates pathological aggression in rodents and humans, particularly in interaction with specific experiences. CONCLUSIONS Feedback to autoreceptors of the 5-HT(1) family and modulation via heteroreceptors are important in the expression of aggressive behavior. Tonic increase of the 5-HT(2) family expression may cause escalated aggression, whereas the phasic increase of 5-HT(2) receptors inhibits aggressive behaviors. Polymorphisms in the genes of 5-HT transporters or rate-limiting synthetic and metabolic enzymes of 5-HT modulate aggression, often requiring interaction with the rearing environment.
Collapse
|
32
|
Santos IMDS, Freitas RLMD, Saldanha GB, Tomé ADR, Jordán J, Freitas RMD. Alterations on monoamines concentration in rat hippocampus produced by lipoic acid. ARQUIVOS DE NEURO-PSIQUIATRIA 2011; 68:362-6. [PMID: 20602036 DOI: 10.1590/s0004-282x2010000300006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Accepted: 11/04/2009] [Indexed: 11/22/2022]
Abstract
The purposes of the present study were to verify monoamines (dopamine (DA), norepinephrine (NE), serotonin (5-HT)), and their metabolites (3,4-hydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA)) contents in rat hippocampus after lipoic acid (LA) administration. Wistar rats were treated with 0.9% saline (i.p., control group) and LA (10, 20 or 30 mg/kg, i.p., LA10, LA20 and LA30 groups, respectively). After the treatments all groups were observed for 24 h. The NE and DA levels were increased only in 20 mg/kg dose of LA in rat hippocampus. Serotonin content and in their metabolite 5-HIAA levels was decreased in same dose of LA. On the other hand, in DOPAC and HVA levels did not show any significant change. The alterations in hippocampal monoamines can be suggested as a possible of brain mechanism of action from this antioxidant. The outcome of the study may have therapeutic implications in the treatment of neurodegenerative diseases.
Collapse
|
33
|
Takahashi A, Quadros IM, de Almeida RMM, Miczek KA. Behavioral and pharmacogenetics of aggressive behavior. Curr Top Behav Neurosci 2011; 12:73-138. [PMID: 22297576 DOI: 10.1007/7854_2011_191] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Serotonin (5-HT) has long been considered as a key transmitter in the neurocircuitry controlling aggression. Impaired regulation of each subtype of 5-HT receptor, 5-HT transporter, synthetic and metabolic enzymes has been linked particularly to impulsive aggression. The current summary focuses mostly on recent findings from pharmacological and genetic studies. The pharmacological treatments and genetic manipulations or polymorphisms of aspecific target (e.g., 5-HT1A receptor) can often result in inconsistent results on aggression, due to "phasic" effects of pharmacological agents versus "trait"-like effects of genetic manipulations. Also, the local administration of a drug using the intracranial microinjection technique has shown that activation of specific subtypes of 5-HT receptors (5-HT1A and 5-HT1B) in mesocorticolimbic areas can reduce species-typical and other aggressive behaviors, but the same receptors in the medial prefrontal cortex or septal area promote escalated forms of aggression. Thus, there are receptor populations in specific brain regions that preferentially modulate specific types of aggression. Genetic studies have shown important gene-environment interactions; it is likely that the polymorphisms in the genes of 5-HT transporters or rate-limiting synthetic and metabolic enzymes of 5-HT (e.g., MAOA) determine the vulnerability to adverse environmental factors that escalate aggression. We also discuss the interaction between the 5-HT system and other systems. Modulation of 5-HT neurons in the dorsalraphe nucleus by GABA, glutamate and CRF profoundly regulate aggressive behaviors. Also, interactions of the 5-HT system with other neuropeptides(arginine vasopressin, oxytocin, neuropeptide Y, opioid) have emerged as important neurobiological determinants of aggression. Studies of aggression in genetically modified mice identified several molecules that affect the 5-HT system directly (e.g., Tph2, 5-HT1B, 5-HT transporter, Pet1, MAOA) or indirectly[e.g., BDNF, neuronal nitric oxide (nNOS), aCaMKII, Neuropeptide Y].The future agenda delineates specific receptor subpopulations for GABA, glutamate and neuropeptides as they modulate the canonical aminergic neurotransmitters in brainstem, limbic and cortical regions with the ultimate outcome of attenuating or escalating aggressive behavior.
Collapse
|
34
|
Gartside SE, Griffith NC, Kaura V, Ingram CD. The neurosteroid dehydroepiandrosterone (DHEA) and its metabolites alter 5-HT neuronal activity via modulation of GABAA receptors. J Psychopharmacol 2010; 24:1717-24. [PMID: 19493957 DOI: 10.1177/0269881109105836] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Dehydroepiandrosterone (DHEA) and its metabolites, DHEA-sulphate (DHEA-S) and androsterone, have neurosteroid activity. In this study, we examined whether DHEA, DHEA-S and androsterone, can influence serotonin (5-HT) neuronal firing activity via modulation of γ-aminobutryic acid (GABA(A)) receptors. The firing of presumed 5-HT neurones in a slice preparation containing rat dorsal raphe nucleus was inhibited by the GABA(A) receptor agonists 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridinyl-3-ol (THIP) (25 μM) and GABA (100 μM). DHEA (100 and 300 μM) and DHEA-S (1, 10 and 100 μM) caused a rapid and reversible attenuation of the response to THIP. DHEA (100 μM) and DHEA-S (100 μM) also attenuated the effect of GABA. Androsterone (10 and 30 μM) markedly enhanced the inhibitory response to THIP (25 μM). The effect was apparent during androsterone administration but persisted and even increased in magnitude after drug wash-out. The data indicate that GABA(A) receptor-mediated regulation of 5-HT neuronal firing is sensitive to negative modulation by DHEA and its metabolite DHEA-S is sensitive to positive modulation by the metabolite androsterone. The effects of these neurosteroids on GABA(A) receptor-mediated regulation of 5-HT firing may underlie some of the reported behavioural and psychological effects of endogenous and exogenous DHEA.
Collapse
Affiliation(s)
- S E Gartside
- Institute of Neuroscience, Newcastle University, Framlington Place, Newcastle upon Tyne, UK.
| | | | | | | |
Collapse
|
35
|
GABA(B) receptor modulation of serotonin neurons in the dorsal raphé nucleus and escalation of aggression in mice. J Neurosci 2010; 30:11771-80. [PMID: 20810897 DOI: 10.1523/jneurosci.1814-10.2010] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The serotonin (5-HT) system in the brain has been studied more than any other neurotransmitter for its role in the neurobiological basis of aggression. However, which mechanisms modulate the 5-HT system to promote escalated aggression is not clear. We here explore the role of GABAergic modulation in the raphé nuclei, from which most 5-HT in the forebrain originates, on escalated aggression in male mice. Pharmacological activation of GABA(B), but not GABA(A), receptors in the dorsal raphé nucleus (DRN) escalated aggressive behaviors. In contrast, GABA agonists did not escalate aggressive behaviors after microinjection into the median raphé nucleus. The aggression-heightening effect of the GABA(B) agonist baclofen depended on the activation of 5-HT neurons in the DRN because it was blocked by coadministration of the 5-HT(1A) agonist 8-OH-DPAT [((+/-)-8-hydroxy-2-(di-n-propylamino)tetralin) hydrobromide] (DPAT), which acts on autoreceptors and inhibits 5-HT neural activity. In vivo microdialysis showed that GABA(B) activation in the DRN increased extracellular 5-HT level in the medial prefrontal cortex. This may be attributable to an indirect action via presynaptic GABA(B) receptors. The presynaptic GABA(B) receptors suppress Ca(2+) channel activity and inhibit neurotransmission, and the coadministration of N-type Ca(2+) channel blocker facilitated the effect of baclofen. These findings suggest that the indirect disinhibition of 5-HT neuron activity by presynaptic GABA(B) receptors on non-5-HT neurons in the DRN is one of the neurobiological mechanisms of escalated aggression.
Collapse
|
36
|
Inyushkin AN, Merkulova NA, Orlova AO, Inyushkina EM. Local GABAergic modulation of the activity of serotoninergic neurons in the nucleus raphe magnus. ACTA ACUST UNITED AC 2010; 40:885-93. [PMID: 20680474 DOI: 10.1007/s11055-010-9337-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2009] [Indexed: 12/18/2022]
Abstract
Experiments on rat brainstem sections in membrane potential clamping conditions addressed the effects of serotonin and GABA on serotoninergic neurons in the nucleus raphe magnus. Local application of serotonin stimulated inhibitory postsynaptic currents (IPSC) in 45% of the serotoninergic neurons studied. This response was not seen in the presence of the fast sodium channel blocker tetrodotoxin. The GABAA receptor antagonist gabazine blocked IPSC in both serotonin-sensitive and serotonin-insensitive neurons. Application of GABA evoked generation of a membrane current (IGABA), which was completely blocked by gabazine. These results indicate self-regulation of the activity of serotoninergic neurons in the nucleus raphe magnus via a negative feedback circuit involving local GABAergic interneurons.
Collapse
Affiliation(s)
- A N Inyushkin
- Samara State University, 1 Academician Pavlov Street, 443016, Samara, Russia.
| | | | | | | |
Collapse
|
37
|
Harsing LG. The pharmacology of the neurochemical transmission in the midbrain raphe nuclei of the rat. Curr Neuropharmacol 2010; 4:313-39. [PMID: 18654635 DOI: 10.2174/157015906778520764] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2005] [Revised: 08/04/2006] [Accepted: 08/16/2006] [Indexed: 01/24/2023] Open
Abstract
Midbrain slices containing the dorsal and medial raphe nuclei were prepared from rat brain, loaded with [(3)H]serotonin ([(3)H]5-HT), superfused and the release of [(3)H]5-HT was determined at rest and in response to electrical stimulation. Compartmental analysis of [(3)H]5-HT taken up by raphe tissue indicated various pools where the neurotransmitter release may originate from these stores differed both in size and rate constant. 5-HT release originates not only from vesicles but also from cytoplasmic stores via a transporter-dependent exchange process establishing synaptic and non-synaptic neurochemical transmission in the serotonergic somatodendritic area. Manipulation of 5-HT transporter function modulates extracellular 5-HT concentrations in the raphe nuclei: of the SSRIs, fluoxetine was found 5-HT releaser, whereas citalopram did not exhibit this effect. Serotonergic projection neurons in the raphe nuclei possess inhibitory 5-HT(1A) and 5-HT(1B/1D) receptors and facilitatory 5-HT(3) receptors, which regulate 5-HT release in an opposing fashion. This observation indicates that somatodendritic 5-HT release in the raphe nuclei is under the control of several 5-HT homoreceptors. 5-HT(7) receptors located on glutamatergic axon terminals indirectly inhibit 5-HT release by reducing glutamatergic facilitation of serotonergic projection neurons. An opposite regulation of glutamatergic axon terminals was also found by involvement of the inhibitory 5-HT(7) and the stimulatory 5-HT(2) receptors as these receptors inhibit and stimulate glutamate release in raphe slice preparation, respectively, Furthermore, postsynaptic 5-HT(1B/1D) heteroreceptors interact with release of GABA in inhibitory fashion in raphe GABAergic interneurons. Serotonergic projection neurons also possess glutamate and GABA heteroreceptors; NMDA and AMPA receptors release 5-HT, whereas both GABAA and GABAB receptors inhibit somatodendritic 5-HT release. Evidence was found for reciprocal interactions between serotonergic and glutamatergic as well as serotonergic and GABAergic innervations in the raphe nuclei. Serotonergic neurons in the raphe nuclei also receive noradrenergic innervation arising from the locus coeruleus and alpha-1 and alpha-2 adrenoceptors inhibited [(3)H]5-HT release in our experimental conditions. The close relation between 5-HT transporter and release-mediating 5-HT autoreceptors was also shown by addition of L-deprenyl, a drug possessing inhibition of type B monoamine oxidase and 5-HT reuptake. L-Deprenyl selectively desensitizes 5-HT(1B) but not 5-HT(1A) receptors and these effects are not related to inhibition of 5-HT metabolism but rather to inhibition of 5-HT transporter.
Collapse
Affiliation(s)
- L G Harsing
- Division of Preclinical REsearch, EGIS Pharmaceuticals, Plc., Bokenyfoldi ut 116, 1165 Budapest, Hungary.
| |
Collapse
|
38
|
Greenwood BN, Strong PV, Fleshner M. Lesions of the basolateral amygdala reverse the long-lasting interference with shuttle box escape produced by uncontrollable stress. Behav Brain Res 2010; 211:71-6. [PMID: 20226213 DOI: 10.1016/j.bbr.2010.03.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2010] [Revised: 03/02/2010] [Accepted: 03/03/2010] [Indexed: 10/19/2022]
Abstract
Exposure to an uncontrollable, but not a controllable, stressor produces a constellation of behaviors called learned helplessness. In rodents, uncontrollable stress interferes with the ability to learn to escape from escapable shocks delivered in a shuttle box. The stress-induced shuttle box escape deficit is a common screening tool for potential antidepressant strategies. Inconsistencies in the literature exist regarding the time-course of, and mechanisms underlying, stress-induced escape deficits. When no common cues are shared between the stressor and testing environment, the escape deficit is short lived and independent of conditioned freezing. In contrast, when stress and testing occur in the same or similar environments, the escape deficit is very long lasting. The current studies address the hypothesis that the long-lived escape deficit produced by uncontrollable stress is dependent upon conditioned fear and the basolateral amygdala (BLA). Rats received bilateral excitotoxic lesions of the BLA 2 weeks following uncontrollable foot shocks. One week after surgery, rats were tested for conditioned freezing and escape behavior in the same shuttle boxes in which prior foot shocks were delivered. Stressed rats with sham lesions displayed robust conditioned freezing and failed to escape during shuttle box testing. Lesions of the BLA eliminated conditioned freezing and completely restored stressed rats' ability to perform the escape contingency. These data indicate that the long-lived stress-induced escape deficit produced under conditions in which the stressor and testing environments share common cues is dependent upon conditioned freezing elicited by the BLA. Results have important implications for the mechanisms underlying learned helplessness phenomena.
Collapse
Affiliation(s)
- Benjamin N Greenwood
- Department of Integrative Physiology and The Center for Neuroscience, University of Colorado-Boulder, Campus Box 354, Boulder, CO 80309, United States.
| | | | | |
Collapse
|
39
|
Shin R, Ikemoto S. The GABAB receptor agonist baclofen administered into the median and dorsal raphe nuclei is rewarding as shown by intracranial self-administration and conditioned place preference in rats. Psychopharmacology (Berl) 2010; 208:545-54. [PMID: 20054525 PMCID: PMC2891391 DOI: 10.1007/s00213-009-1757-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2009] [Accepted: 12/09/2009] [Indexed: 10/20/2022]
Abstract
RATIONALE The midbrain raphe regions have long been implicated in affective processes and disorders. There is increasing evidence to suggest that the median (MR) and dorsal raphe nuclei (DR) tonically inhibit reward-related processes. OBJECTIVES Stimulation of GABAB receptors in the midbrain raphe nuclei is known to inhibit local neurons, especially serotonergic neurons. We sought to determine if injections of the GABAB receptor agonist baclofen into the MR or DR are rewarding, using intracranial self-administration and conditioned place preference. RESULTS Rats quickly learned to lever press for infusions of baclofen (0.1–2.5 mM) into the MR, but not the ventral tegmental area or central linear nucleus. Rats increased lever pressing associated with intra-DR baclofen infusions, but not readily. Baclofen self-administration into the MR or DR was attenuated by coadministration of the GABAB receptor antagonist SCH 50911 (1 mM) or systemic pretreatment with the dopamine receptor antagonist SCH 23390 (0.025 mg/kg, i.p.). In addition, intra-DR and intra-MR injections of baclofen induced conditioned place preference; injection into DR was more effective. CONCLUSIONS Baclofen injections into the midbrain raphe nuclei are rewarding. Baclofen was more readily self-administered into the MR than into the DR, while baclofen injections into the DR more readily induced conditioned place preference than those into the MR. These sites may be differentially involved in aspects of reward. These findings suggest that MR or DR neurons containing GABAB receptors are involved in tonic inhibitory control over reward processes.
Collapse
Affiliation(s)
- Rick Shin
- Behavioral Neuroscience Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, 251 Bayview Blvd., Suite 200, Baltimore, MD 21224, USA
| | - Satoshi Ikemoto
- Behavioral Neuroscience Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, 251 Bayview Blvd., Suite 200, Baltimore, MD 21224, USA
| |
Collapse
|
40
|
|
41
|
Cryan JF, Slattery DA. GABAB Receptors and Depression: Current Status. GABABRECEPTOR PHARMACOLOGY - A TRIBUTE TO NORMAN BOWERY 2010; 58:427-51. [DOI: 10.1016/s1054-3589(10)58016-5] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
42
|
Cooperative opioid and serotonergic mechanisms generate superior antidepressant-like effects in a mice model of depression. Int J Neuropsychopharmacol 2009; 12:1033-44. [PMID: 19341511 DOI: 10.1017/s1461145709000236] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Although complete remission of symptoms is the goal of any depression treatment, many patients fail to attain or maintain a long-term, symptom-free status. The opioid system has been implicated in the aetiology of depression, and some preclinical and clinical data suggest that opioids possess a genuine antidepressant-like effect. This study aimed to investigate a potential antidepressant strategy combining different classes of monoaminergic compounds with the weak mu-opioid agonist codeine in the tail suspension test in mice, a paradigm aimed at screening potential antidepressants. The results showed that codeine produced an antidepressant-like effect when administered alone, that was effectively antagonized by the opioid antagonist naloxone. The combination of subeffective doses of codeine with the selective serotonin reuptake inhibitors (fluoxetine or citalopram) lead to an accentuated reduction in immobility time. In contrast, immobility time remained unchanged when codeine was combined with a noradrenaline reuptake inhibitor (desipramine) or with a noradrenaline/serotonin reuptake inhibitor (duloxetine). The immobility time also remained unchanged with the combination of subeffective doses of codeine plus (+/-)-tramadol (weak mu-opioid agonist with serotonin/noradrenaline reuptake inhibitor properties) or (-)-tramadol (noradrenaline reuptake inhibitor). Conversely, the combination with (+)-tramadol (mu-opioid agonist with serotonin reuptake inhibitor properties) produced a large decrease in the immobility time. All these combinations were without effects on motor behaviour in mice. These data support the hypothesis that a combination of classical serotonergic antidepressants and weak opioid receptor agonists may be a helpful new strategy in the treatment of refractory depression.
Collapse
|
43
|
Ferreira PMP, Militão GCG, Freitas RM. Lipoic acid effects on lipid peroxidation level, superoxide dismutase activity and monoamines concentration in rat hippocampus. Neurosci Lett 2009; 464:131-4. [PMID: 19703522 DOI: 10.1016/j.neulet.2009.08.051] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2009] [Revised: 08/14/2009] [Accepted: 08/19/2009] [Indexed: 10/20/2022]
Abstract
The purposes of the present work were to verify lipid peroxidation level, superoxide dismutase (SOD) activity and monoamines (dopamine (DA), norepinephrine (NE), serotonin (5-HT)), and their metabolites (3,4-hydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA)) contents in rat hippocampus after lipoic acid (LA) administration. Wistar rats were treated with 0.9% saline (i.p., control group) and LA (10, 20 or 30 mg/kg, i.p., LA10, LA20 and LA30 groups, respectively). After the treatments all groups were observed for 24h. In LA20 group only there was a significant decrease in lipid peroxidation level. However, no alteration was observed in SOD activity in groups treated with LA. The NE and DA levels were increased only in 20mg/kg dose of LA in rat hippocampus. Serotonin content and their metabolite 5-HIAA levels was decreased in same dose of LA. On the other hand, DOPAC and HVA levels did not show any significant change. The reduction in lipid peroxidation level and alterations in hippocampal monoamines can be suggested as a possible brain mechanism from this antioxidant. The outcome of the study may have therapeutic implications in the neurodegenerative diseases.
Collapse
Affiliation(s)
- P M P Ferreira
- Laboratory of Physiology and Pharmacology of Federal University of Piauí, Piauí, Brazil
| | | | | |
Collapse
|
44
|
Mamelak M. Narcolepsy and depression and the neurobiology of gammahydroxybutyrate. Prog Neurobiol 2009; 89:193-219. [PMID: 19654034 DOI: 10.1016/j.pneurobio.2009.07.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2009] [Revised: 05/24/2009] [Accepted: 07/28/2009] [Indexed: 12/23/2022]
Abstract
A voluminous literature describes the relationship between disturbed sleep and depression. The breakdown of sleep is one of the cardinal features of depression and often also heralds its onset. Frequent arousals, periods of wakefulness and a short sleep onset REM latency are typical polysomnographic features of depression. The short latency to REM sleep has been attributed to the combination of a monoaminergic deficiency and cholinergic supersensitivity and these irregularities have been proposed to form the biological basis of the disorder. A similar imbalance between monoaminergic and cholinergic neurotransmission has been found in narcolepsy, a condition in which frequent awakenings, periods of wakefulness and short sleep onset REM latencies are also characteristic findings during sleep. In many cases of narcolepsy, this imbalance appears to result from a deficiency of hypocretin but once established, whether in depression or narcolepsy, this disequilibrium sets the stage for the dissociation or premature appearance of REM sleep and for the dissociation of the motor inhibitory component of REM sleep or cataplexy. In the presence of this monoaminergic/cholinergic imbalance, gammahydroxybutyrate (GHB) may acutely further reduce the latency of REM sleep and induce cataplexy, in both patients with narcolepsy or depression. On the other hand, the repeated nocturnal application of GHB in patients with narcolepsy improves the continuity of sleep, prolongs the latency to REM sleep and prevents cataplexy. Evidence to date suggests that GHB may restore the normal balance between monoaminergic and cholinergic neurotransmission. As such, the repeated use of GHB at night and the stabilization of sleep over time makes GHB an effective treatment for narcolepsy and a potentially effective treatment for depression.
Collapse
Affiliation(s)
- Mortimer Mamelak
- Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada.
| |
Collapse
|
45
|
Nishiyama T. Interaction between midazolam and serotonin in spinally mediated antinociception in rats. J Anesth 2009; 23:249-55. [PMID: 19444565 DOI: 10.1007/s00540-009-0740-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2008] [Accepted: 01/09/2009] [Indexed: 10/20/2022]
Abstract
PURPOSE Intrathecal administration of serotonin (5-HT) is antinociceptive through the involvement of spinal cord gamma-aminobutyric acid (GABA) receptors. Therefore, 5-HT would interact with the GABA agonist, midazolam, which is well known to exert spinally mediated antinociception in the spinal cord. The present study investigated the antinociceptive interaction between spinally administered 5-HT and midazolam, using two different rat nociceptive models. METHODS Sprague-Dawley rats with lumbar intrathecal catheters were tested for their thermal tail withdrawal response and paw flinches induced by formalin injection after the intrathecal administration of midazolam or 5-HT, or the midazolam/ HT combination. The effects of the combination were tested by isobolographic analysis, using the combination of each 1, 1/2, 1/4, 1/8, and 1/16 of the 50% effective dose (ED50). The total fractional dose was calculated. Behavioral side effects were also examined. RESULTS 5-HT alone and midazolam alone both showed dose-dependent antinociception in both the tail flick test and the formalin test. The ED50 of the combination was not different from the calculated additive value either in the tail flick test or in phase 2 of the formalin test, but it was significantly smaller than the calculated additive value in phase 1 of the formalin test. The total fractional dose value was 0.90 in the tail flick test, 0.093 in phase 1 of the formalin test, and 1.38 in phase 2 of the formalin test. The agitation, allodynia, or motor disturbance observed with either agent alone was not seen with the combination treatment. CONCLUSION The antinociceptive effects of intrathecal midazolam and 5-HT were additive on thermal acute and inflammatory facilitated stimuli, and synergistic on inflammatory acute stimulation.
Collapse
Affiliation(s)
- T Nishiyama
- Department of Anesthesiology and Intensive Care, Kamagaya General Hospital, 929-6 Hatsutomi, Kamagaya, 273-0121, Japan
| |
Collapse
|
46
|
Küçükibrahimoğlu E, Saygin MZ, Calişkan M, Kaplan OK, Unsal C, Gören MZ. The change in plasma GABA, glutamine and glutamate levels in fluoxetine- or S-citalopram-treated female patients with major depression. Eur J Clin Pharmacol 2009; 65:571-7. [PMID: 19373461 DOI: 10.1007/s00228-009-0650-7] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2008] [Accepted: 03/27/2009] [Indexed: 12/14/2022]
Abstract
OBJECTIVE The aim of this study was to investigate the relationship between plasma glutamate, glutamine and gamma-aminobutyric acid (GABA) levels in female patients with major depression treated with S-citalopram or fluoxetine. METHODS The patients were assigned into S-citalopram (10 mg/day) or fluoxetine (20 mg/day) groups (n = 15 per group). The Hamilton and Beck Depression Inventory Scales were performed on all study participants, and blood samples were collected. The same procedures were repeated 10 days following the onset of therapy. Fifteen female healthy volunteers were also included in the study for the evaluation of normal plasma levels. RESULTS The plasma GABA levels of the healthy volunteers were higher whereas those for glutamate and glutamine were lower than the day zero samples of the patients. An increase in plasma GABA levels and a decrease in glutamate and glutamine levels were observed on the 10th day of treatment. No difference was detected between the drug treatments. CONCLUSION Our findings may suggest that GABA, glutamate and glutamine play a role in depression and that plasma GABA may be used as a biomarker for treatment control.
Collapse
Affiliation(s)
- Esra Küçükibrahimoğlu
- Department of Pharmacology and Clinical Pharmacology, Marmara University School of Medicine, Haydarpaşa, Istanbul 34668, Turkey
| | | | | | | | | | | |
Collapse
|
47
|
Abstract
OBJECTIVES It has been proposed that major depression is associated with a dysfunction of the gamma-aminobutyric acid (GABA) system. This study was planned to investigate whether there are any alterations in GABAergic activities in major depressive patients and, if there are, whether electroconvulsive therapy (ECT) has any effect on these changes. METHODS Twenty-five depressed inpatients who responded to a course of ECT and 23 healthy subjects were included in the study. Serum GABA levels were measured 2 days before and 10 minutes after the first ECT and 3 days after the last ECT, and a baclofen challenge test was performed 2 days before the first ECT and 3 days after the last ECT in the patients. The same tests were carried out only once in the control group. RESULTS Depressive patients had lower serum GABA levels compared with healthy individuals, and ECT caused a significant increase in these levels. The acute effect of the one-ECT procedure was a huge increase in the baseline GABA levels. Although there was no difference in the maximum alteration in growth hormone with baclofen between the patients and controls before the therapeutic ECT course, it became significantly higher in the depressive patients than in the controls after the treatment. CONCLUSIONS The findings of this study support the GABA deficit hypothesis of major depression because major depressive patients have lower levels of serum GABA that are increased by a completed ECT course. ECT seems to increase brain GABA levels as well as GABAB activity, and these effects may contribute to its mechanism of therapeutic effect.
Collapse
|
48
|
Papp A, Juranyi Z, Nagymajtenyi L, Matyus P, Harsing LG. The synaptic and nonsynaptic glycine transporter type-1 inhibitors Org-24461 and NFPS alter single neuron firing rate in the rat dorsal raphe nucleus. Further evidence for a glutamatergic-serotonergic interaction and its role in antipsychotic action. Neurochem Int 2007; 52:130-4. [PMID: 17669555 DOI: 10.1016/j.neuint.2007.06.030] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2007] [Revised: 06/04/2007] [Accepted: 06/07/2007] [Indexed: 11/21/2022]
Abstract
Single neuron firing rate was recorded from dorsal raphe nucleus of anesthetized rats. The firing rate of raphe neurons varied from 4 to 8 discharge per second before drug administration and this neuronal activity was decreased by L-701,324 (2 mg/kg i.v. injection), a competitive antagonist of glycineB binding site of N-methyl-D-aspartate (NMDA) receptors. The glycine transporter type-1 (GlyT1) antagonists Org-24461 (10 mg/kg i.v.) and NFPS (3 mg/kg i.v.) reversed the inhibitory effect of L-701,324 on single neuron activity recorded from dorsal raphe nucleus of the rat. Org-24461 and NFPS both tended to increase the raphe neuronal firing rate also when given alone but their effect was not significant. This finding serves further evidence that glutamate released from axon terminals of the cortico-striatal projection neurons stimulates serotonergic neurons in the raphe nuclei and this effect is mediated at least in part by postsynaptic NMDA receptors. Thus, GlyT1 inhibitors are able to reverse the hypofunctional state of NMDA receptors, suggesting that these drugs may have beneficial therapeutic effects in neurological and psychiatric disorders characterized with impaired NMDA receptor-mediated transmission.
Collapse
Affiliation(s)
- Andras Papp
- Department of Public Health, Szent-Gyorgyi Medical University, Szeged, Hungary
| | | | | | | | | |
Collapse
|
49
|
Fichna J, Janecka A, Costentin J, Do Rego JC. The endomorphin system and its evolving neurophysiological role. Pharmacol Rev 2007; 59:88-123. [PMID: 17329549 DOI: 10.1124/pr.59.1.3] [Citation(s) in RCA: 180] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Endomorphin-1 (Tyr-Pro-Trp-Phe-NH2) and endomorphin-2 (Tyr-Pro-Phe-Phe-NH2) are two endogenous opioid peptides with high affinity and remarkable selectivity for the mu-opioid receptor. The neuroanatomical distribution of endomorphins reflects their potential endogenous role in many major physiological processes, which include perception of pain, responses related to stress, and complex functions such as reward, arousal, and vigilance, as well as autonomic, cognitive, neuroendocrine, and limbic homeostasis. In this review we discuss the biological effects of endomorphin-1 and endomorphin-2 in relation to their distribution in the central and peripheral nervous systems. We describe the relationship between these two mu-opioid receptor-selective peptides and endogenous neurohormones and neurotransmitters. We also evaluate the role of endomorphins from the physiological point of view and report selectively on the most important findings in their pharmacology.
Collapse
Affiliation(s)
- Jakub Fichna
- Laboratory of Experimental Neuropsychopharmacology, CNRS FRE 2735, IFRMP 23, Faculty of Medicine & Pharmacy, University of Rouen, 22, Boulevard Gambetta, 76183 Rouen cedex, France
| | | | | | | |
Collapse
|
50
|
Massé F, Hascoët M, Bourin M. Effect of GABAergic ligands on the anxiolytic-like activity of DOI (a 5-HT(2A/2C) agonist) in the four-plate test in mice. Eur Neuropsychopharmacol 2007; 17:483-91. [PMID: 17196374 DOI: 10.1016/j.euroneuro.2006.11.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2006] [Revised: 10/13/2006] [Accepted: 11/14/2006] [Indexed: 11/23/2022]
Abstract
5-HTergic and GABAergic systems are involved in neurobiology of anxiety. Precedent studies have demonstrated that SSRIs possessed an anxiolytic-like effect in the four-plate test (FPT) at doses that did not modify spontaneous locomotor activity. This effect seems to be mediated through the activation of 5-HT(2A) postsynaptic receptors. The purpose of the present study was to examine the implication of GABA system in the anxiolytic-like activity of DOI in the FPT. To achieve this, the co-administration of DOI (5-HT(2A/2C) receptor agonists) with GABA(A) and GABA(B) receptor ligands was evaluated in the FPT. Alprazolam, diazepam and muscimol (for higher dose) potentiated the anxiolytic-like effect of DOI. Bicuculline, picrotoxin and baclofen inhibited the anxiolytic-like effect of DOI. Flumazenil and CGP 35348 had no effect on the anxiolytic-like activity of DOI. These results suggest that the GABA system seems to be strongly implicated in the anxiolytic-like activity of DOI in the FPT.
Collapse
Affiliation(s)
- Fabienne Massé
- EA 3256 "Neurobiologie de l'Anxiété et de la Dépression", Faculté de Médecine, BP 53508, 1 rue Gaston Veil, F44035 Nantes cedex 01, France
| | | | | |
Collapse
|