Effect of Metabolic Alkalosis on Adrenal Medullary Secretion in the Dog

Abstract

Adrenal venous blood was collected in dogs anesthetized with sodium pento-barbital and analyzed for adrenaline and noradrenaline by the fluorimetric me-thod. Metabolic alkalosis was induced by the intravenous infusion of 1M sodium bicarbonate or 1M sodium carbonate. By the infusion of sodium bicarbonate, arterial blood pH was elevated to 7.71-7.75. However, no increase in the adrenal medullary secretion could be observed. In dogs infused with sodium carbonate, arterial blood pH elevated above 7.81 and the secretion rates of adrenaline and noradrenaline were significantly increased concomitantly with development of metabolic alkalosis. In dogs, whose splanchnic nerves were previously cut, the infusion of sodium carbonate did not increase the adrenal medullary secretion, although arterial blood pH exceeded 7.81. Thus it is concluded that severe metabolic alkalosis increases the adrenal medullary secretion through the central nervous mechanism.