LYSINE ACETYLSALICYLATE MODIFIES APHAGIA AND THERMOGENIC CHANGES INDUCED BY LATERAL HYPOTHALAMIC-LESION

These experiments test the effect of intraperitoneal injection of lysi ne acetylsalicylate on 1) food intake and 2) the sympathetic and therm ogenic changes induced by lesion of the lateral hypothalamus (LH). Foo d intake, firing rate of the nerves innervating interscapular brown ad ipose tissue (IBAT), and IBAT and colonic temperatures (T-IBAT and T-C ) were monitored in male Sprague-Dawley rats lesioned in the LH. These variables were measured before and after intraperitoneal injection of lysine acetylsalicylate. The same variables were also monitored in 1) lesioned rats with intraperitoneal administration of saline, 2) sham- lesioned animals with intraperitoneal injection of lysine acetylsalicy late, and 3) sham-lesioned rats with intraperitoneal injection of sali ne. The results show that lysine acetylsalicylate modifies the aphagia by increasing food intake and also reduces the enhancements in firing rate, T-IBAT, and T-C induced by LH lesion. These findings suggest th at prostaglandin synthesis plays a key role in the control of eating b ehavior in LH-lesioned rats by acting on the sympathetic and thermogen ic changes induced by LH lesion.