Chemistry and enterohepatic circulation of bile acids.

A brief review is given of the chemistry of bile acids, emphasizing the relationship between chemical structure, physical properties and enterohepatic cycling of the major primary and secondary bile acids. Features of the enterohepatic circulation of primary and secondary bile acids in man are summarized. The effects of bile acid feeding on the composition of the enterohepatic circulation in man are reviewed. Methods for characterizing the enterohepatic circulation of bile acids in man are tabulated.