DISTRIBUTION OF INJECTED CORTISOL-4-C14IN NORMAL AND SHOCKED RATS

Abstract

THE mechanism by which cortisol or any other adrenocortical hormone fulfills its physiological function is unknown. It appears reasonable to assume that the active principle is being attached to the protein structure of the target tissue prior to its specific action; such possible combinations with protoplasmic receptors have been discussed for steroid hormones in general (1). Labeling with radiocarbon or tritium has been used to follow in the rodent the metabolic fate of testosterone (2), progesterone (2, 3, 4), cortisone (5, 6) and cortisol (7). In most of these studies the steroid doses administered exceeded physiological concentrations and the time periods investigated were generally of the order of hours or days. The present study was undertaken in order to elucidate the fate of cortisol-4-C¹⁴ during the first hour after administration. The doses given were near the physiological level of the 17-hydroxycorticosteroids (8). The first phase of this investigation is concerned with the distribution of cortisol or its metabolites in normal rats and in rats subjected to tourniquet shock.