Sodium transport inhibitor from bovine hypothalamus

A low molecular weight, basic, nonpeptidic factor that possesses sodium transport inhibitory properties has been prepared from bovine hypothalamus by acid/acetone extraction and gel filtration. Concentration and partial purification was achieved by ion-exchange chromatography. This substance inhibits active Na+ transport across anuran membranes, inhibits ouabain binding to frog urinary bladder, and directly inhibits renal Na+,K+-ATPase. This substance thus possesses the putative characteristics of a natriuretic factor of hypothalamic origin.