ANTINATRIURETIC EFFECT OF EXOGENOUS METABOLIC SUBSTRATES ON SODIUM DIURESIS OF SALINE INFUSION

The sodium diuresis of acute saline infusion was studied in dogs with intravenous infusion of 140 milliequivalent/liter sodium solutions, of which 20 milliequivalent sodium was present as bicarbonate or as lactate, pyruvate, and alpha-ketoglutarate. The natriuresis was inhibited sizably by use of the metabolic anions and the inhibition was accomplished theough augmented tubular reabsorption of filtered sodium ion, whether or not alpha-adrenergic receptor blockade was induced by phenoxybenzamine. The results suggest that blood levels of renal metabolic substrate may play a role in the regulation of sodium excretion during blood volume expansion with saline and be part of an anti-natriuretic system concerned with body sodium and volume homeostasis. © 1968.