Medial and lateral hypothalamic oxygen consumption as a function of age, starvation and glucose administration in...

In fed rats, in vitro oxygen consumption of the ventromedial hypothalamus (VMH) was found to be reliably higher than that of the lateral hypothalamus (LHA), and this differential effect was abolished by prior food deprivation. Neither body weight (236-569 g) nor age (50-180 days old) was important in determining the magnitude of differential respiration of these hypothalamic subareas. VMH respiration was found to be especially responsive to intragastric administration of glucose-oxygen consumption increasing 94% above baseline levels in VMH, with only a 28% increment occurring in the LHA. Using various delays between loading of glucose and testing, the VMH-LHA ratio in oxygen consumption was found to be inversely related to food intake. Implications of these findings to the nature of hypothalamic control of feeding are discussed.