Metaplastic Regulation of the Median Raphe Nucleus via Serotonin 5-HT1A Receptor on Hippocampal Synaptic Plasticity Is Associated With Gender-Specific Emotional Expression in Rats
| Autor: | Yoshiki Yanagawa, Hiroki Shikanai, Hiroko Togashi, Machiko Matsumoto, Yasuhiro Saito, Keiichi Shimamura, Sachiko Hiraide, Sumitaka Inoue, Mitsuhiro Yoshioka |
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| Jazyk: | angličtina |
| Rok vydání: | 2014 |
| Předmět: |
Male
medicine.medical_specialty Serotonin Median raphe nucleus Long-Term Potentiation Hippocampus Biology Serotonergic Internal medicine Conditioning Psychological LTP induction medicine Animals Humans Rats Wistar Pharmacology Metaplasia Sex Characteristics Neuronal Plasticity Mental Disorders lcsh:RM1-950 Long-term potentiation Fear Rats Expressed Emotion Endocrinology lcsh:Therapeutics. Pharmacology nervous system Synaptic plasticity Synapses Molecular Medicine 5-HT1A receptor Raphe Nuclei Female Neuroscience Receptors Serotonin 5-HT1 Stress Psychological |
| Zdroj: | Journal of Pharmacological Sciences, Vol 124, Iss 3, Pp 394-407 (2014) |
| ISSN: | 1347-8613 |
| Popis: | Gender differences in psychiatric disorders are considered to be associated with the serotonergic (5-HTergic) system; however the underlying mechanisms have not been clearly elucidated. In this study, possible involvement of the median raphe nucleus (MRN)-hippocampus 5-HTergic system in gender-specific emotional regulation was investigated, focusing on synaptic plasticity in rats. A behavioral study using a contextual fear conditioning (CFC) paradigm showed that the females exhibited low anxiety-like behavior. Extracellular 5-HT levels in the hippocampus were increased by CFC only in the males. Long-term potentiation (LTP) in the hippocampal CA1 field was suppressed after CFC in the males, which was mimicked by the synaptic response to MRN electrical stimulation. In the MRN, 5-HT immunoreactive cells significantly increased in the females compared with those in the males. Pretreatment with the 5-HT1A receptor agonists tandospirone (10 mg/kg, i.p.) and 8-OH DPAT (3 mg/kg, i.p.) significantly suppressed LTP induction in the males. Synaptic responses to CFC and 5-HT1A receptor interventions were not observed in the females. These results suggest that the metaplastic 5-HTergic mechanism via 5-HT1A receptors in the MRN-hippocampus pathway is a key component for gender-specific emotional regulation and may be a cause of psychiatric disorders associated with vulnerability or resistance to emotional stress. Keywords:: gender difference, serotonin, hippocampus, long-term potentiation, serotonin 5-HT1A receptor |
| Databáze: | OpenAIRE |
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