Alteration of bile acid metabolism in two-thirds hepatectomized rat

Bile acid metabolism after two-thirds partial hepatectomy (PH) in rat was studied. Bile acid kinetics (i.e. synthesis rate and pool size) were determined by wash out method combined with gas liquid chromatography, and serum bile acids by gas liquid chromatography-mass spectrometry. Serum bile acid concentration was highest on the third day after PH, as the liver regeneration progressed but it gradually decreased with increasing cholic acid (CA)/chenodeoxycholic acid (CDCA), reflecting impaired hepatic uptake of bile acids and/or cholestasis during the early post-hepatectomy period. Predominance of CA in bile acid synthesis, pool, and biliary secretion was also found. On the third day after PH, liver weight recovered to 66% of the control value, but enhancement of bile acid synthesis was not observed. Consequently, pool size remained at 50% of control. On the seventh day, synthesis of bile acid, especially of CA, was enhanced and pool size and liver weight returned to 68 and 72% of the respective control values. Bile acid synthesis was returned to the control value on the fourteenth day with concomitant restoration of liver weight and bile acid pool size. These changes in bile acid kinetics parallel the events during hepatic regeneration after PH.