Aldosterone: Clinical Aspects

Abstract

Aldosterone is a potent mineralocorticoid synthesized by the outer zone of the adrenal cortex, the zona glomerulosa. Production of aldosterone is stimulated by angiotensin and potassium, but may also be affected by over 20 other endogenous and exogenous substances. Because of its sensitivity to angiotensin, secretion of aldosterone is altered by diseases that affect the kidneys and perturb their release of renin. Examples include renal artery stenos is, which increase s renin secretion, and diabetes, which reduces it. Other disease s that reduce perfusion of the kidneys also alter aldosterone secretion. Examples include heart failure and cirrhos is of the liver, both of which stimulate renin release and increa se ald ostero ne sec ret io n. Disorders of the adrenal cortex can affect aldosterone secretion. Adenomas of th e zona glomerulosa overproduce aldosterone independent of angiotensin. Hypertrophy of the zona glomerulosa causes overproduction of aldosterone because the cells are hypersensitive to angiotensin. The role of aldosterone in common cardiovascular diseases such as heart failure, low-renin essential hypertension, and the hypertension that accompanies obesity, is uncertain. The growing use of plasma aldosterone and renin measurements and the development of new aldosterone antagonists should clarify the importance of this steroid in a variety of disease states