THE EFFECTS OF CORTISONE AND HYDROCORTISONE ON WATER DIURESIS AND RENAL FUNCTION IN MAN

Abstract

Prolonged oral or intramuscular administration of large doses of cortisone and hydrocortisone increased the maximal rate of water diuresis in man. The increase consisted chiefly of an increase in free-water clearance. There was a small rise in glomerular filtration rate (GFR) which did not parallel the increase in urine flow. A single intravenous infusion of hydrocortisone regularly produced an increase in glomerular filtration rate, but without a consistent increase in the diuretic response to water loading. Observations indicate that continued administration of steroid in large doses influences the renal tubular reabsorption of water. It is suggested that more free water is made available for excretion because of (1) a redistribution of solute reabsorption between proximal and distal systems or (2) an alteration in the permeability of the renal tubular epithelium to water.