Hypothermia following injection of 2-deoxy-D-glucose into selected hypothalamic sites

Abstract

From our previous studies with 2-deoxy-D-glucose (2-DG) an inhibitor of glucose utilization, we postulated that the resultant intracellular glucopenia affects central neuronal pathways involved in the control of peripheral heat production. In this investigation, we have delineated these thermoregulatory sites by stereotaxically injecting microquantities of 2-DG into the hypothalamus of the rat and monitoring core temperature (Tre). After stabilization of Tre at a room temperature of 23 +/- 1 degree C, 20 microgram of 2-DG in 2 microliter was injected into 350- to 400-g rats. Significant decreases in Tre were noted after injections into the anterior hypothalamic, ventromedial, and dorsomedial nuclei as well as the lateral and posterior hypothalamic areas. Mean nadir Tre decreased 1.5 degrees C 1 h after, was significantly depressed 3.5 h after, and returned to basal values 4 h after administration of 2-DG into the ventral premammillary nucleus (PMV). Dose-dependent response was observed for injections into the PMV only. Of a total of 21 sites studied in the anterior and posterior hypothalamus, the PMV, an area of unknown physiological function, was the most sensitive to glucose deprivation.