THE EFFECT OF ADRENAL STEROIDS ON PERIPHERAL FAT MOBILIZATION IN THE RAT1

Abstract

The fasting adrenalectomized rat moved more fat out of the epididymal fat depot during a 12-hour fast than did the normal animal. Restoration of cortical hormone (hydrocortisone) at both high and low dose levels elicited a marked inhibition of fat movement out of this depot. The administration of hydrocortisone to intact animals also produced this inhibition. The procedure of sham adrenalectomy caused a significant diminution of fat mobilization from the epididymal depot for at least six days following the laparotomy. This response to trauma has now been observed in another laboratory following a burn stress. There are probably factors other than the release of cortical steroids which mediate this response but an increase in steroid titer appears to alter fat mobilization in this direction. The hypophysectomized animal behaves differently from the adrenalectomized animal in this regard. The amount of fat moved out of the epididymal depot by the hypophysectomized animal during a 12-hour fast was much smaller than that moved by either the intact or adrenalectomized animal. Administration of cortical hormones alone did not restore the rate of fat movement to normal. Work is in progress using combinations of target gland hormones and growth hormone in hypophysectomized animals.