Observations on the Sodium-Retaining Corticoid in the Urine of Children and Adults in Relation to Sodium Balance and Edema1

Abstract
Forty-eight specimens of urine from normal adults and children and from hospitalized patients were extracted with chloroform within 40 minutes after acidification to pH 1.0. The Na-retaining activity of the extracted material was measured by bioassay. Significant Na-retaining activity was observed in extracts prepared from the urine of a number of edematous patients with lipemic nephrosis, cardiac failure, and hepatic cirrhosis. Urine extracts from normal men and women often had an opposite effect, tending to increase the excretion of Na in the adrenalectomized rats, resembling the effect of hydrocortisone in the bioassay used. Increased Na-retaining activity was found in the urine of some normal men and women when Na intake was reduced to 11 meq/day. The level of Na-retaining activity appeared to be related to the daily output of Na by the patient, rather than to a specific disease, to the state of hydration, or to urine flow. The Na-retaining activity of extracts of urine from several patients with lipemic nephrosis, cardiac failure, or hepatic cirrhosis was found in the same chromatographic fraction of each extract tested. Some normal men on low Na diets showed increased activity in the same fraction of the chromatograms. This fraction was observed to contain a corticosteroid which is presumed to be aldosterone on the basis of its chromatographic and biologic properties.