Sympathetic nervous system involvement in the lateral hypothalamic lesion syndrome.
The role of the sympathetic nervous system in the lateral hypothalamic syndrome of body-weight loss was investigated. Bilateral electrolytic lesions of the lateral hypothalamus (LH) were performed in 90-day-old male albino rats. In experiment 1, the splanchnic nerves were resected at 35 days (right) and 70 days (left) postlesion. In experiment 2, bilateral adrenal demedullations were performed in a second group of rats with LH lesions (LH rats) at 35 days postlesion. The results indicated that lesions of the lateral hypothalamic area lowered body-weight maintenance levels to approximately 87% of nonlesion control values. Bilateral splanchnicetomy produced a significantly greater body-weight loss in nonlesion animals than in LH rats. Following adrenal demedullation, nonlesion rats also reduced body-weight levels whereas LH rats significantly increased weight-maintenance levels. In addition, the adrenal glands of LH rats with sham demedullations weighed significantly more than the adrenals of nonlesion-sham demedullated animals. These data are discussed in relation to metabolic-autonomic mechanisms that may play a role in LH lesion-induced weight loss.
D000313:Adrenal Medulla / Q000378:metabolism / Q000503:physiopathology; D000818:Animals; D001835:Body Weight; D003714:Denervation; D007031:Hypothalamus / Q000503:physiopathology*; D008297:Male; D051381:Rats; D013153:Splanchnic Nerves / Q000503:physiopathology; D013564:Sympathetic Nervous System / Q000503:physiopathology*; D013997:Time Factors; D014628:Vagotomy