Background/aims: Changes in bile acid synthesis during liver regeneration after hepatectomy is little known in humans. Since it has been reported that the serum 7 alpha-hydroxycholesterol levels reflect the hepatic bile acid synthesis and that the determination of bile acid synthesis is useful to assess the liver regeneration rate, we determined the serum 7 alpha-hydroxycholesterol level during liver regeneration after hepatectomy in clinical patients.
Methodology: The serum 7 alpha-hydroxycholesterol levels were determined by gas-liquid chromatography-mass spectrometry-selected ion monitoring method before and on days 1, 3, 5, 7, 14 and 21 after hepatectomy in twenty consecutive patients.
Results: The 7 alpha-hydroxycholesterol levels became lower between days 1 and 7, were increased on day 14, and then decreased on day 21 after hepatectomy. The patients with preoperative external biliary drainage showed a higher serum 7 alpha-hydroxycholesterol level than those without biliary drainage before hepatectomy. The former showed lower serum 7 alpha-hydroxycholesterol levels than the latter throughout the 21 days after hepatectomy. In patients whose liver resection rate was more than 50%, the serum 7 alpha-hydroxycholesterol levels were kept lower until 21 days after hepatectomy compared with those whose liver was excised less than 50%.
Conclusions: It is concluded that the patients who had preoperative biliary drainage or major hepatic resection seem to have less hepatic reserve capacity for bile acid synthesis after hepatectomy.