ALDOSTERONE IS THE MAIN MINERALOCORTICOID SECRETED BY THE ADRENAL CORTEX. THE MAIN MINERALOCORTICOID ACTIONS ARE ON FLUID AND ELECTROLYTE BALANCE. THEY ENHANCE SODIUM REABSORPTION IN THE KIDNEY AND HENCE EXPAND THE EXTRACELLULAR FLUID VOLUME, AND THEY ENHANCE RENAL EXCRETION OF POTASSIUM AND H+IONS.