INTERACTION OF GLUCOCORTICOID AND INSULIN IN THE RESPONSES OF RATS TO STARVATION-REFEEDING

Experiments designed to determine whether the role of glucocorticoid (GC) in the induction of the enzyme overshoot response to starvation-refeeding was direct or permissive through insulin were conducted. Intact, adrenalectomized (ADX), and steptozotocin (STREP) treated rats with or without insulin and/or CC replacements were starved for 48 hours and refed a 65% glucose diet for 48 hours. The typical enzyme overshoot response to starvation-refeeding was observed in the intact rats, ADX rats given GC, STREP rats given insulin and ADX-STREP rats given glucocorticoid plus insulin. No overshoot was observed if glucocorticoid was absent whereas a modest increase in enzyme activity could be observed in insulin deficient rats treated with GC.