ABSTRACT
Aldosterone, the major circulating mineralocorticoid, is a steroid hormone produced exclusively in the zona glomerulosa. The major regulators of aldosterone biosynthesis and secretion are the renin-angiotensin system and potasssium ion concentrations. Minor regulators include adrenocorticotropic hormone (ACTH) from the pituitary, atrial natriuretic peptide from the heart, and dopamine secreted locally in the adrenal. A number of aldosterone precursors, including deoxycorticosterone and 18-hydroxycorticosterone, have mineralocorticoid activity, and their hypersecretion in various pathological states may produce or exacerbate features typical of mineralocorticoid hypertension. Aldosterone acts mainly on the distal nephron, although several other sites of sodium reabsorption exist.
