Expression of serotonin 5-HT2C receptors in GABAergic cells of the anterior raphe nuclei

We have used double in situ hybridization to examine the cellular localization of 5-HT2C receptor mRNA in relation to serotonergic and GABAergic neurons in the anterior raphe nuclei of the rat. In the dorsal and median raphe nuclei 5-HT2C receptor mRNA was not detected in serotonergic cells identifi...

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Detalles Bibliográficos
Autores: Serrats, Jordi, Mengod Los Arcos, Guadalupe, Cortés, Roser
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2005
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/112670
Acceso en línea:http://hdl.handle.net/10261/112670
Access Level:acceso abierto
Palabra clave:GAD
5-HT transporter
5,7-DHT
In situ hybridization
Serotonergic lesions
Median raphe
Dorsal raphe
Descripción
Sumario:We have used double in situ hybridization to examine the cellular localization of 5-HT2C receptor mRNA in relation to serotonergic and GABAergic neurons in the anterior raphe nuclei of the rat. In the dorsal and median raphe nuclei 5-HT2C receptor mRNA was not detected in serotonergic cells identified as those expressing serotonin (5-HT) transporter mRNA. In contrast, 5-HT2C receptor mRNA was found in most GABAergic cells, recognized by the presence of glutamic acid decarboxylase mRNA. Such 5-HT2C receptor-positive GABAergic neurons were mainly located in the intermediolateral and lateral portions of the dorsal raphe and lateral part of the median raphe. The present data give anatomical support to a previous hypothesis that proposed a negative-feedback loop involving reciprocal connections between GABAergic interneurons bearing 5-HT2A/2C receptors and 5-HT neurons in the dorsal raphe and surrounding areas. According to this model, the excitation of GABAergic interneurons through these 5-HT 2C (and also 5-HT2A) receptors would result in the suppression of 5-HT cell firing. © 2004 Elsevier B.V. All rights reserved.