Dietary fat exacerbates liver disease in bile duct-ligated rats

Previous studies have suggested that the mortality of bile duct-ligated (BDL) rats is related to the amount of dietary fat consumed. We investigated the influence of dietary fat concentration on liver disease in BDL rats. Groups of rats were fed for 4 wk either a low fat diet (LF, 0.92 kJ/g; 3% of total energy from fat), a high fat diet (HF, 1.07 kJ/g; 30% fat), a high fat diet with energy density equivalent to that of the LF diet (HFIB, 0.92 kJ/g; 30% fat) or a diet based on the composition of commercial nonpurified diets (COMP, 0.90 kJ/g; 10% fat). Energy intake, body weight gain, plasma biochemical indices and hepatic histology were compared in BDL and sham-operated control rats. Bile duct-ligated animals consuming the LF diet showed a faster recovery of energy intake and greater body weight gain following surgery than did BDL animals fed the other three diets. Plasma alkaline phosphatase activity was significantly greater in BDL animals fed either of the high fat diets than in those fed the LF or COMP diet starting 1 and 2 wk, respectively, after surgery. Hepatic fibrosis and bile duct proliferation at d 28 post-ligation were greater in rats fed a 30% fat (HF) diet than in rats fed the 3% fat (LF) diet. These results suggest that dietary fat concentration can influence the severity of liver dysfunction in extrahepatic biliary obstruction.