ACTH in Aldosterone Physiology The role of corticotrophin (adrenocorticotrophic hormone: ACTH) in aldosterone secretion is not entirely clear; it is more effective in salt-depleted subjects than in those with normal salt balance, and is probably relatively unimportant in the normal situation. There is also evidence of the existence of other factors, as yet unknown. Although acute administration of ACTH stimulates aldosterone secretion, chronic ACTH excess is associated with normal or even low levels of aldosterone. Thus, when the renin-angiotensin system is suppressed, for example in patients with primary hyperaldosteronism, ACTH may play an important role.