Hepatic-intestinal disposal of endogenous human alpha atrial natriuretic factor99-126 (ANF) was assessed in 13 patients with cirrhosis (six Child-Turcotte class A, five class B, and two class C) and eight control subjects. The Fick principle was applied during hepatic vein catheterization. Arterial ANF concentration in patients with cirrhosis [11.1 +/- 1.6 (SEM) pmol/L] was not significantly different from that of the control subjects (14.9 +/- 4.2 pmol/L, NS). Arteriohepatic venous extraction ratio of ANF (0.43 +/- 0.05 in cirrhosis vs 0.37 +/- 0.09 in controls, NS), hepatic-intestinal clearance (274 +/- 46 vs 237 +/- 46 ml/min, NS) and removal rate (2.9 +/- 0.88 vs 3.1 +/- 0.77 pmol/min, NS) were closely similar in patients and controls. The present results give no indication that significantly reduced hepatic-intestinal disposal of ANF has a role in causing altered circulating plasma levels of this peptide in cirrhosis. This is in keeping with the presence of vascular clearance receptors and peptidases for ANF degradation independent of hepatocellular function.