VASOPRESSIN STIMULATION OF THE ISOLATED ADRENAL GLANDS: NATURE AND MECHANISM OF HYDROCORTISONE SECRETION12

Abstract
By means of direct arterial per -fusion of the adrenal glands of the hypophysectomized dog, it has been shown that synthetic lysine, arginine and acetyl arginine vasopressins stimulate the adrenal cortex directly to secrete hydrocortisone. Maximal cortisol secretion occurred at dose ranges of 100 to 400 milliunits per minute, with minimal activity being detected with values as low as 1 milliunit per minute of arginine vasopressin. At maximal dosages the response was comparable to that seen following 1 unit per minute of ACTH. Pressor activity and cortisol stimulating activity were demonstrated to be independent to each other. In addition similar polypeptides such as oxytocin, insulin and glucagon and pressor amines such as epinephrine and norepinephrine did not show any cortisol stimulating activity. ACTH was consistently found to increase aldo-sterone secretion when perfused through the glands of hypophysectomized animals. The probable role of arginine vasopressin as a factor in the stress reaction is discussed as well as its posulated ability to activate adrenal phosphorylase.