Role of gluco- and mineralocorticoids in salt and water metabolism of adrenalectomized dogs

Abstract

Daily doses (5 mg) of 1-dehydrohydrocortisone reduces plasma Na and Cl of nonfasted adrenalectomized dogs to levels characteristic of severe insufficiency. The animals remain active and vigorous despite the distorted plasma electrolyte pattern. Blood pressure and plasma volume remain at or near control values. The glucocorticoid maintains a normal internal distribution of fluid and certain electrolytes between intra- and extracellular compartments. Aldosterone even in large doses apparently lacks those properties necessary to enable the fasted adrenalectomized dog exhibiting symptoms to shift fluids from one compartment to another hence is incapable of reviving animals from insufficiency and restoring activity and vigor. The data suggest that the primary action of aldosterone is on the kidney and through renal control of Na excretion serves to regulate the fluid and Na content of the extracellular compartment.