Clinical Information Discusses physiology, pathophysiology, and
general clinical aspects, as they relate to a laboratory test
Aldosterone stimulates sodium transport across cell membranes,
particularly in the distal renal tubule where sodium is
exchanged for hydrogen and potassium. Secondarily, aldosterone
is important in the maintenance of blood pressure and blood
volume. Aldosterone is the major mineralocorticoid and is
produced by the adrenal cortex. The renin-angiotensin system is
the primary regulator of the synthesis and secretion of
aldosterone. Likewise, increased concentrations of potassium in
the plasma may directly stimulate adrenal production of the
hormone. Under physiologic conditions, pituitary
adrenocorticotropic hormone can stimulate aldosterone secretion.
Urinary aldosterone levels are inversely correlated with urinary
sodium excretion. Normal subjects will show a suppression of
urinary aldosterone with adequate sodium repletion. Primary
hyperaldosteronism, which may be caused by aldosterone