Abstract
Adrenocortical activity in the dog was studied during the first 4 hours after X-irradiation of the adrenal with doses of 200-2, 000 R. Under anesthetized conditions, the secretory activity was determined by measuring 11-hydroxycorticosteroids in the adrenal venous blood. The adrenocortical activity was found to be stimulated by localized X-irradiation of 800-2, 000 R to the adrenal, the response being roughly proportional to the dose. However, with hypophysectomized dogs, the adrenocortical secretory response to X-irradiation of the adrenal was entirely absent, probably as a result of hypophysectomy. These results suggest that the X-irradiation doses of 800-2, 000 R in the present study, if delivered directly to the adrenal, produce an augmentation in the corticoid secretory activity and its action occurs through the pituitary-adrenocortical mechanism.
