Citalopram reduces social interaction in rats by activation of serotonin (5-HT)2C receptors

The selective serotonin (5-HT) reuptake inhibitor (SSRI), citalopram (2.5 mg/kg, s.c.), reduced social interaction (SI) in rats. This action was abolished by the 5-HT2B/2C receptor antagonist, SB206,553 (0.63 mg/kg. s.c.), and the 5-HT2C receptor antagonist. SB242,084 (0.04 mg/kg. i.p.), but not by the 5-HT2A antagonist, MDL100,907 (0.04 mg/kg, s.c.), thc 5-HT1A antagonist. WAY100,635 (0.16 mg/kg, s.c.), or the 5-HT3 antagonist, ondansetron (0.16 mg/kg, s.c.). These data suggest that 5-HT2C receptors are involved in the "anxiogenic" actions of citalopram. (C) 2000 Elsevier Science Ltd. All rights reserved.