NITRATE KINETICS IN PATIENTS WITH COMPENSATED CIRRHOSIS - CORRELATIONWITH HEMODYNAMICS

Objectives: The serum nitrate concentration is known to be increased i n patients with cirrhosis. This study was designed to determine the ki netics of nitrate in the splanchnic vascular areas and its relationshi p with hepatic hemodynamics in patients with compensated cirrhosis. Me thods: We measured the serum nitrate concentration of various sites, i ncluding the femoral artery, hepatic vein, azygos vein, and pulmonary artery, and compared these values with hepatic hemodynamics. Results: The nitrate concentrations of hepatic vein and azygos vein were signif icantly greater in cirrhotic patients compared with those of control s ubjects. The values were particularly elevated in patients with Child- Pugh's class B. In control subjects, hepatic vein and azygos vein nitr ate concentrations were significantly lower than arterial nitrate conc entrations whereas nitrate concentrations were significantly greater i n the hepatic and azygos veins than femoral artery in cirrhotic patien ts, and nitrate kinetics was that of the net release of nitrate from t he hepatic and azygos veins. The portal vein blood flow positively cor related with the nitrate concentration of azygos vein, pulmonary arter y, and femoral artery. Conclusions: The present results implicate the enhanced production of nitric oxide in the mesenteric vascular beds in patients with cirrhosis. The positive correlation between portal vein blood flow and serum nitrate concentrations suggests that endogenous nitric oxide may have an important role in the regulation of portal he modynamics in these patients.