Stimulation of rat adrenocortica secretion by a factor present in human urine.

Production of corticosteroids by the rat adrenal gland has been studied in vitro. Both a commercial and a highly purified preparation of ACTH stimulated the secretion of “corticosterone” and aldosterone in vitro. The “corticosterone” fraction was increased more than aldosterone. Addition of the nonultrafilterable fraction of human urine to the incubate stimulated the secretion of aldosterone more than “corticosterone.” Several possible interpretations of this effect arc discussed.