ABSTRACT
The effect of some serotonin receptor antagonists was investigated on the body temperature of male mice. These antagonists produced significant reductions of body temperature in methamphetamine-induced hyperthermic male mice. Thus, the hyperthermia induced by metha-mphetamine [11 mol/kg,i.p..] was antagonized by the previous i.p. administration of 1.06 Amol/kg NAN-190 [5-HTIA receptor antagonist], 22.1 Amol/kg methiothepin [5-HT IB/ID receptor antagonist], 2.13 iimol/kg methysergide [5-HT 2,v2B receptor antagonist], 3.3 ktmol/kg mianserin [5-HT2c and a2 - adrenoceptor antagonist] or 0.003 Amol/kg ondansetron [5-HT3 receptor antagonist]. The present results indicate that central serotonin receptors may he involved in the hyperthermic effect of methamphetamine. Ondansetron, being effective at a relatively small dose [0.003 Amol/kg] as compared to other antagonists used in this study, may be a potential antidote for methamphetamine-induced hyperthermia