mineralocorticoid /min′əral′ōkôr″tikoid/ [L, minera + cortex, bark; Gk, eidos, form] , a hormone, secreted by the adrenal cortex, that maintains normal blood volume, promotes sodium and water retention, and increases urinary excretion of potassium and hydrogen ions. Aldosterone, the most potent mineralocorticoid with regard to electrolyte balance, acts on the distal tubules of the kidneys to enhance the reabsorption of sodium into the plasma. Trauma and stress increase mineralocorticoid secretion. The synthetic mineralocorticoid fludrocortisone, which has mineralocorticoid and glucocorticoid activity, is used to treat the salt-losing adrenogenital syndrome and the severe corticoid deficiency characteristic of Addison’s disease. See also glucocorticoid.
