Cyproheptadine antagonism of p-chloroamphetamine hypothermia in mice

Serotonin and 5-hydroxyindoleacetic acid levels were measured in the brains of mice following intraperitoneal administration of 10 mg/kg p-chloramphetamine (PCA). Indolyl levels were decreased at the 60 min interval, but were unchanged 30 min following PCA injection. PCA-induced hypothermia was found to be dependent upon dose and ambient temperature. Hypothermia was attenuated by cyproheptadine and slightly enhanced in the presence of fluoxetine. Mechanisms other than intraneuronal release and serotonin depletion appear to mediate PCA-induced hypothermia.