aldosterone
n. the principle mineralocorticoid hormone secreted by the adrenal cortex, the outer layer of the adrenal gland. It helps to regulate mineral and water metabolism by promoting potassium excretion and sodium retention in the kidneys. Excess secretion of aldosterone results in a pathological condition called aldosteronism (or hyperaldosteronism), marked by headaches, muscle weakness, fatigue, hypertension, and numbness. Primary aldosteronism is caused by abnormal functioning of the adrenal cortex itself and is called Conn’s syndrome, whereas secondary aldosteronism is the result of a liver, heart, or kidney disease affecting the adrenal glands.