An N-acyl glycyltaurine conjugate of deoxycholic acid in the biliary bile acids of the rabbit

Abstract

jj biliary bile acid composition of the adult and neonatal domestic rabbit, as well as that of the adult brush rabbit, was characterized. In adult domestic rabbits, the dominant bile acid present was deoxycholic acid (88% of total bile acids), a secondary bile acid formed by the bacterial 7-dehydroxylation of cholic acid. Although most of the bile acids present were conjugated with glycine, two exceptions were observed. About 3% of deoxycholic acid was conjugated, in N-acyl linkage, with glycyl-taurine. Chenodeoxycholic acid, which composed <1% of wile acids, was conjugated solely with taurine. The bile of neonatal rabbits contained a greater percentage of primary bile acids, and bile acids were conjugated to a much greater extent with taurine. The adult brush rabbit had a bile acid composition similar to that of the domestic rabbit, but about one-third of all bile acids were conjugated with taurine. In addition, lithocholic acid was present as its sulfated amidate, whereas in the domestic rabbit, lithocholic acid was conjugated solely with glycine. The biliary bile acid composition of rabbits appears to be unique both in terms of the predominant steroid moiety, as well as in the modes of conjugation.