Pharmacology Biochemistry & Behavior, Vol. 5, pp. 79-83. Copyright © 1976 by ANKHO International Inc. All rights of reproduction in any form reserved. Printed in the U.S.A.

Hypothermia Induced by ag-Tetrahydrocannabinol in Rats With Electrolytic Lesions of Preoptic Region WILLIAM T. S C H M E L I N G 2 A N D M I C H A E L J. H O S K O

Department o f Pharmacology, Medical College o f Wisconsin, Milwaukee, WI 53233 (Received 10 F e b r u a r y 1976) SCHMELING, W. T. AND M. J. HOSKO. Hypothermia induced by a9-tetrahydrocannabinol in rats with electrolytic lesions of the preoptic region. PHARMAC. BIOCHEM. BEHAV. 5(1) 79-83, 1976. - The preoptic region (POR) is a primary central site for thermoregulation. Bilateral lesions of POR disrupt thermoregulation, and in rats, produce a characteristic syndrome including hyperthermia, a9-Tetrahydrocannabinol ("9-THC), a potent hypothermic agent, appears to mediate this effect via some central mechanism. The studies reported here suggest that ~9-THC induces hypothermia at a site other than POR. Male Sprague-Dawley rats were divided into 2 groups, one with subsequently confirmed bilateral POR lesions and a sham operated group. The lesioned animals developed hyperthermia (+2.1 ° ± 0.1°C, p