AJP - Regulatory, Integrative and Comparative Physiology, Vol 232, Issue 3 128-R136, Copyright © 1977 by American Physiological Society
Sympathetic nervous system involvement in the lateral hypothalamic lesion syndrome
C. A. Opsahl
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.
