Serum Antidiuretic Substances and Urinary Corticosteroid in The Human*

ALARGE body of evidence indicates that the adrenal cortical steroids are of primary importance in regulating the rate of renal excretion of water and conservation of salt and that they are necessary to achieve diuresis following intake of large amounts of water (reviewed by Gaunt, Birnie and Eversole (1)). Posterior pituitary extract has converse actions; that is, it causes water retention and salt excretion (reviewed by Irving (2)). Silvette and Britton (3) first suggested that these hormones which have opposite effects may reciprocate in regulating water and salt excretion. This report describes a study of this relationship in the human. Recently, Birnie and associates (4) have demonstrated an antidiuretic substance (ADS) in the serum of rats. We have found that antidiuretic activity in human serum can be detected by the same technique. Birnie and his co-workers (5) have data which suggest that the material found in rat serum is probably formed in the neurohypophysis. The origin of the material found in human serum is not known. It is felt that the antidiuretic activity of serum represents the algebraic sum of substances producing water retention and of substances causing diuresis.