부산대학교 도서관

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.euroneuro.2009.06.011 Byline: Robert L. Gannon (a), Jean-Louis Peglion (b), Mark J. Millan (c) Keywords: Suprachiasmatic nucleus; Serotonin receptors; Raphe nucleus; Biological rhythms; Selective serotonin reuptake inhibitors Abstract: Though serotonergic mechanisms modulate circadian rhythms, roles of individual serotonin (5-HT) receptors remain uncertain since data are lacking for antagonists. Herein, both the 5-HT.sub.5A receptor antagonist, A843277 (10mg/kg), and the 5-HT.sub.1B antagonist, SB224289 (1mg/kg), inhibited light-induced phase advances in hamster circadian wheel-running rhythms. Conversely, though 5-HT.sub.1A and 5-HT.sub.7 receptors are likewise implicated in circadian scheduling, their blockade by WAY100635 (0.5mg/kg) and SB269970 (1mg/kg), respectively, was ineffective. Since actions of 5-HT reuptake inhibitors are modified by antagonists, we evaluated their influence on suppression of phase advances by citalopram (10mg/kg). Its action was potentiated by WAY100635 and the 5-HT.sub.2C antagonist, SB242084 (1mg/kg), but not by A842377, SB224289, SB269970, and antagonists at 5-HT.sub.2A (MDL100907) and 5-HT.sub.6 (SB399885) receptors. In conclusion, this is the first in vivo evidence for an influence of 5-HT.sub.5A receptors upon circadian rhythms, but no single class of 5-HT receptor mediates their control by citalopram. Author Affiliation: (a) Department of Biology, Valdosta State University, Valdosta, Georgia, USA (b) Chimie B, Institut de Recherches Servier, Val d'or, Suresnes, France (c) Psychopharmacology Department, Institut de Recherches Servier, Croissy-sur-Seine, France Article History: Received 16 April 2009; Revised 6 June 2009; Accepted 16 June 2009