Effects of sodium acetylsalicylate on body temperature of monkeys under heat exposure

Abstract

Exposure of Taiwan monkeys to 38 degrees C ambient temperature caused: a) raised body temperature, b) restlessness and struggling, c) increased evaporative heat loss and d) increase in tail skin temperature. After the administration of sodium acetylsalicylate, 100 to 250 mg/kg intraperitoneally or 4 to 15 mg intracerebroventricularly (third ventricle) the same heat load caused: a) less increase in body temperature, b) no restlessness or struggling, c) an initially higher rate of evaporative heat loss and d) higher tail skin temperature. Larger doses of acetylsalicylate caused greater antihyperthermic effects. Intracerebroventricular injection was more effective than the intraperitoneal route. These data show that acetylsalicylate improved tolerance of animals to external heat loads. The magnitude of body temperature elevation during heat exposure was reduced in the presence of acetylsalicylate by activation of heat-dissipating mechanisms, presumably through the central nervous system.