Effects of brain serotonin alterations on hypothermia produced by chlorpromazine in rats

Depressing functional serotonin or depleting serotonin levels in rat brains with either p-chlorophenylalanine, 5,6-dihydroxytryptamine or raphe lesions greatly enhanced hypothermia induced by chloropromazine (CPZ). Depressing the firing of raphe units or decreasing serotonin turnover in the brain with either a serotonin precursor (tryptophan) or the inhibitors of serotonin re-uptake (Lilly 1 10140 and chlorimipramine) also greatly enhanced the CPZ-induced hypothermia. The data indicate that serotonergic activity in the brain plays a role in the elaboration or modulation of CPZ hypothermia.