Portal hypertension after bile duct obstruction: effect of bile diversion on portal pressure in the rat.

Biliary obstruction of 14 and 28 days induced in the rat an increase of portal pressure (PP) and wedge hepatic vein pressure (WHVP); the higher these were, the longer was the obstruction. Occurrence of portal hypertension seemed related to portal and periportal fibrosis. Relief of obstruction after 14 days by bilioduodenal anastomosis brought back to normal PP and WHVP. In rats with longer obstruction periods, bilioduodenal anastomosis failed to lower PP and WHPV although biological signs of cholestasis returned to normal levels. These results suggest that portal hypertension may arise very shortly after biliary obstruction in rats and that it may persist in animals with a prolonged biliary obstruction despite an efficient bile drainage. In clinical conditions, such results would favor early treatment of lesions that usually cause prolonged bile duct obstruction, such as postoperative bile duct stenosis.