Effect of lateral hypothalamic lesion on brown adipose tissue of Zucker lean and obese rats.
Acute (10-day) lateral hypothalamic (LH) lesion induced a reduction of food intake in both lean and obese Zucker rats which averaged about 50% over the course of the first 10 days. The aphagia associated with a fall in body weight in both genotypes which was greater than their respective pair-fed controls, indicating a change in energetic efficiency. The reduced level of BAT protein, mitochondria and GDP binding observed in the obese rat was restored after LH lesion, suggesting the reestablishment of a normal sympathetic drive to the tissue. The markedly lower plasma insulin concentration in the LH lesioned obese rat is consistent with a reduction in parasympathetic activity in these animals. Food restriction in the sham lean rat reduced BAT protein content and mitochondrial GDP binding, whereas no such changes were observed in the food restricted obese rat. This demonstrates the insensitivity of the obese rat to dietary signals and may imply that LH lesion restores diet-induced BAT thermogenesis in the obese rat.
D002001:Adipose Tissue, Brown / Q000502:physiology*; D000818:Animals; D001833:Body Temperature Regulation; D001835:Body Weight; D001931:Brain Mapping; D004435:Eating; D007026:Hypothalamic Area, Lateral / Q000502:physiology*; D007328:Insulin / Q000097:blood; D051381:Rats; D011924:Rats, Zucker; D012931:Social Environment
D007328:Insulin