One hundred and eight patients with cirrhosis (23 grade A, 46 grade B and 39 grade C, according to Pugh's classification) underwent hemodynamic studies and plasma catecholamine concentration measurements. Blood samples were withdrawn from the pulmonary artery (n = 108), the hepatic vein (n = 108), the azygos vein (n = 59), the right renal vein (n = 66), the right jugular vein (n = 34) and the femoral vein (n = 33). Plasma noradrenaline concentrations in the pulmonary artery and the hepatic vein were more elevated in grade B (607 +/- 52 and 402 +/- 42 pg/ml, respectively) and C patients (630 +/- 59 and 475 +/- 53 pg/ml, respectively) than in grade A patients (411 +/- 51 and 243 +/- 40 pg/ml, respectively). Plasma noradrenaline concentrations from these two vessels were negatively correlated with indocyanine green clearance. These results indicate that both overall and splanchnic sympathetic activities are dependent on altered hepatic function. Significant correlations were found between the wedged hepatic venous pressure and plasma noradrenaline concentrations from either the pulmonary artery, the hepatic vein or the azygos vein. These correlations indicate that both overall and splanchnic sympathetic activities are dependent on the degree of portal hypertension. Moreover, significant correlations were found between hepatic venous plasma noradrenaline concentrations and systemic hemodynamic values, suggesting that splanchnic sympathetic nervous activity could either play a role in the systemic hyperkinetic syndrome or be a consequence of this hyperkinetic syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)