STUDIES ON THE ADRENAL

Abstract

Of 180 double adrenalectomized rats, 158 lived less than 22 days. In the remaining 22 rats (all weighing over 100 gm., and including all cases of apparently indefinite survival), operative removal of active adrenal tissue was found incomplete. Similarly, of 36 adrenalectomized rabbits, 31, in which no adrenal tissue was found at autopsy, survived 9 days or less; in those surviving longer periods, bits of adrenal or cortical tissue were found. The results indicate that the general belief in the frequency of scattered adrenal tissue in the rat and the rabbit is unfounded, and that indefinite or prolonged survival is due to incomplete extirpation, which consists either in allowing cortical remnants of the main glands to be left behind, or in failing to remove the scattered accessory nests of cells present in the peritoneal tissue in the neighborhood of the glands. The assumption of the existence of widespread accessory tissue is unnecessary. Factors in addition to surgical technique which influence length of survival after adrenalectomy are: species and age of animal, pre- and postoperative treatment, anesthetic used and duration of anesthesia, and completeness of extirpation. Young rats may be used for the assay of cortical extracts.