Profiles of bile acids and their glucuronide and sulphate conjugates in the serum, urine and bile from patients undergoing bile drainage.

Bile acid profiles in serum, urine, and bile from patients undergoing bile drainage and the changes of serum bile acids after bile drainage were studied. Bile acids were separated into non-glucuronidate-non-sulphate, glucuronidated, and sulphated fractions and were measured by mass fragmentography using conjugates of deuterium labelled bile acids as internal standards. Glucuronidated and sulphated bile acids contribute 14-32% and 16-44% of serum bile acids, 4-11% and 61-82% of urine bile acids and 0.2-1% and 0.3-2% of biliary bile acids respectively. After bile drainage the concentration of serum non-glucuronidated-non-sulphated bile acids decreased more rapidly than glucuronidated and sulphated bile acids. There was little biliary excretion of the glucuronidated and sulphated bile acids. Such conjugation appears to have a role in facilitating bile acid excretion by the urinary route.