Deficits of temperature regulation in rats with hypothalamic lesions.

HAN, PAUL W. AND JOHN R. BROBECK. Dejcits of tem@rature regulation in rats with hyfwthalamic lesions. Am. J. Physiol. 200 (4) : 707-7 10. I 96 I .-Temperature regulation was studied in rats with bilateral hypothalamic lesions, by observing body temperature responses to the heat stress of forced exercise, and to exposure to hot or cold environments. Lesions in the preoptic area caused impairment of heat loss mechanisms but no disturbance of regulation against cold. Lesions in the lateral hypothalamic area caused no disturbance of regulation against cold; regulation against heat exposure was also not significantly altered, but the cause of a higher T-cut observed after exercise could not be explained. Lesions in other parts of the hypothalamus, with the exception of the ventromedial nuclei, did not cause changes in the normal pattern of temperature response to forced exercise.