Enzyme Overshoot in Starved-Refed Rats: Role of the Adrenal Glucocorticoid

Intact and adrenalectomized (ADX) rats were starved for 48 hours and refed a 65% glucose diet for 48 hours. Isotonic saline or 8 azaguanine (8AZ) and/or glucocorticoid was administered to the animals during the refeeding period. The typical enzyme overshoot response to refeeding was observed in the intact rats and in the ADX rats given hormone replacement. No overshoot was observed in ADX rats without hormone replacement or in the intact or in hormone treated ADX rats injected with 8AZ. These results suggest that glucocorticoid is involved in the genesis of the enzyme overshoot response to starvation-refeeding, perhaps through an effect on de novo RNA synthesis.