Augmented endogenous nitric oxide production in partial portal vein-ligated rats

Nitric oxide and the liver

In recent years, the role of nitric oxide (NO) in the pathogenesis of liver disease and its complications has been extensively studied. There remain, however, many areas of controversy. In particular, the effect of NO on vascular function in the systemic circulation and the hepatic microcirculation has received the greatest attention. It has been proposed on the one hand that increased NO synthesis is responsible for the development of the hyperdynamic circulation in cirrhosis, while decreased production of NO within the hepatic microcirculation may be important in the development of parenchymal tissue damage and the onset of portal hypertension. The purpose of this review is to examine the available data concerning the role of NO in liver disease and to discuss some of the controversies and contradictions that surround it.

Transjugular intrahepatic portosystemic shunt: a successful treatment for hepatopulmonary syndrome

Hepatopulmonary syndrome is a well described complication of chronic liver disease. Though uncommon, it carries a high morbidity and mortality. The pathogenesis of the syndrome has not been clearly defined. Portal hypertension seems to play a crucial role in the pathogenesis of the syndrome, probably by enhancing nitric oxide production. As yet, no pharmacological therapy has been proven effective. Many reports of successful reversal of the syndrome after liver transplantation have been published. We report a patient with hepatopulmonary syndrome who showed a significant and durable (4 months') improvement in his symptoms, arterial oxygenation, and intrapulmonary shunts, as calculated by radionuclide studies after transjugular intrahepatic portosystemic shunt placement. Transjugular intrahepatic portosystemic shunt may represent a durable treatment option for patients with hepatopulmonary syndrome.