Evidence that d-fenfluramine anorexia is mediated by 5-HT1 receptors.
The effects of eight serotonin (5-HT) receptor antagonists on the anorectic effect of d-fenfluramine (3.0 mg/kg, IP) were examined in a test of sweet mash consumption, using non-deprived male rats. d-Fenfluramine's effect was attenuated by the mixed 5-HT1/5-HT2 receptor antagonists, methiothepin and metergoline; by the 5-HT2 receptor antagonist ritanserin; and by (+/-)cyanopindolol, a mixed 5-HT1A/5-HT1B receptor antagonist. In contrast, d-fenfluramine's effect was not antagonised by the 5-HT2 receptor antagonists ketanserin and ICI 169 369; the 5-HT3 receptor antagonist ICS 205 930; or by xylamidine, a peripheral 5-HT receptor antagonist. In this feeding model, none of the 5-HT antagonists, when tested alone, had any effect to increase palatable food consumption. The pattern of results obtained strongly suggest that central 5-HT1 receptors play an important role in the mediation of d-fenfluramine-induced anorexia.
Neill
J C
JC
School of Psychology, University of Birmingham, UK.
Cooper
S J
SJ
D000578:Amidines / Q000494:pharmacology; D000818:Animals; D001067:Appetite Depressants; D005277:Fenfluramine / Q000494:pharmacology*; D008297:Male; D008711:Metergoline / Q000494:pharmacology; D010869:Pindolol / Q000031:analogs & derivatives / Q000494:pharmacology; D010880:Piperidines / Q000494:pharmacology; D051381:Rats; D011985:Receptors, Serotonin / Q000187:drug effects*; D016713:Ritanserin; D012702:Serotonin Antagonists / Q000494:pharmacology
D000578:Amidines; D001067:Appetite Depressants; D010880:Piperidines; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; D016713:Ritanserin; D008711:Metergoline; D005277:Fenfluramine; C047975:cyanopindolol; D010869:Pindolol; C005894:xylamidine