Functional renal failure of cirrhosis (FRFC) is a usually fatal syndrome of acute renal failure occurring in patients with advanced liver disease. Although not conclusively proven, most evidence suggests that renal arterial and arteriolar vasoconstriction is the cause of the renal failure in these patients. However, the mediators of the vasoconstriction remain unknown. Human atrial natriuretic factor (hANF) is a hormone with potent natriuretic, diuretic, and vasorelaxant properties. A deficiency of hANF could lead to renal arterial vasoconstriction and avid renal sodium retention as seen in FRFC. This study was undertaken to determine if patients with FRFC are deficient in circulating hANF. Seven patients with advanced alcoholic liver disease and renal failure of unknown cause (FRFC) were compared with 7 patients with advanced alcoholic liver disease, ascites, and normal serum creatinine as well as with 14 healthy volunteers. Plasma hANF was measured by radioimmunoassay. Plasma hANF was 742 +/- 227 pg/ml (mean +/- SEM) in patients with FRFC compared with 360 +/- 70 pg/ml in patients with liver disease and normal serum creatinine (p greater than 0.05) and 28 +/- 5.7 pg/ml in healthy volunteers (p less than 0.005 vs. FRFC and chronic liver disease, ascites, and normal serum creatinine). Thus, FRFC is not caused by a deficiency of circulating hANF. The elevated plasma hANF levels in patients with chronic liver disease and continued sodium retention may suggest a renal insensitivity to the natriuretic effects of hANF.