THE EFFECT OF A SALT LOAD AND ALDOSTERONE ON THE ACID-BASE-EQUILIBRIUM AND ON THE ELECTROLYTES IN BLOOD AND URINE OF NORMAL SUBJECTS FOLLOWING CHEMICAL BLOCKADE OF THE ADRENAL CORTEX

Abstract

ABSTRACT In four subjects receiving a standard diet the endogenous production of aldosterone and of cortisol was suppressed by the combined administration of dexamethasone and metopirone. The experiments were completed by acute intravenous infusion of NaCl and of NaCl plus aldosterone, respectively. The Na+ and K+ balance, acid-base-equilibrium and steroid excretion were followed up. Cortisol and cortisone disappeared from the urine after dexamethasone, aldosterone only after additional treatment with metopirone. The ratio free/conjugated 17-OHCS in urine increased significantly. Na+ excretion went up under combined treatment with the two drugs. Intravenously administered aldosterone resulted in a definite but limited Na+ retention associated with a slight increase in K+ excretion. The effective H+ excretion was closely related to the dietary intake of Na+ and K+. The K+/H+ ratio in urine remained unaltered irrespectively of whether aldosterone was added to a NaCl infusion or not. The results obtained in blood were somewhat conflicting. No significant changes in Na+ and K+ were observed throughout the experiment. All four volunteers developed a metabolic alkalosis.