Early metabolic changes following destruction of the ventromedial hypothalamic nuclei.

Studies were performed to determine whether increased gluconeogenesis precedes or is necessary for increased lipogenesis after ventromedial hypothalamic destruction. Weanling male rats were injected with 14C-bicarbonate or with 3H2O to assess gluconeogenesis or lipogenesis, respectively, at various short time intervals after placement of hypothalamic lesions. Lipogenesis increased within 2 hr of lesion placement whereas gluconeogenesis did not change for at least 4 hr. The results indicate that lipogenesis increases before gluconeogenesis and, therefore, that enhanced glucose production is not necessary for increased lipogenesis to occur in these rats.