Influence of the adrenal gland on hypothermic response of the rat to chlorpromazine, reserpine and serotonin

¹ Physiology Division, Directorate of Medical Research, U.S. Army Chemical Warfare Laboratories, Army Chemical Center, Maryland

This study was made to determine the influence of the adrenal gland on the temperature response of the rat to chlorpromazine, reserpine and serotonin. It was found that endogenous epinephrine does not enter into the thermoregulatory response to chlorpromazine. While the cortical factors do not prevent a hypothermia, they do inhibit this response from reaching excessive levels and in time permit a complete recovery. Both epinephrine and the cortical factors, however, play a role in the temperature response to serotonin and reserpine. The data indicate that either epinephrine or serotonin alone can cause a marked hypothermia. Injected together, however, a mutual antagonism is evident and the hypothermic response is inhibited or delayed. While the cortical factors are sufficient to prevent excessive hypothermia and mortality of serotonin-treated rats, these plus epinephrine are necessary to assure survival in the reserpine-treated animal. The data emphasize the marked influence which epinephrine might exert on other serotonin or reserpine-induced responses.