Metabolism of Bile Alcohols, 24-Nor-5β-cholestane-3α, 7α, 12α, 24-tetrol and 3α, 7α, 12α-Trihydroxy-26, 27-dinor-5β-cholestan-24-one, in Rats

Abstract

24-Nor-5β-cholestane-3α, 7α, 12α, 25-tetrol and 3α, 7α, 12α-trihydroxy-26, 27-dinor-5β-cholestan-24-one were administered intraperitoneally to bile fistula rats, and the metabolites excreted in the bile were analyzed. No formation of bile acids from these bile alcohols was observed. 7α, 12α, 25-Trihydroxy-24-nor-5β-cholestane-3α-O-(β-D-glucopyranosid) uronic acid was identified as the only biliary metabolite of the 24-nor-5β-cholestanetetrol. The major metabolite of the trihydroxy-26, 27-dinor-5β-cholestanone was 7α, 12α-dihydroxy-24-oxo-26, 27-dinor-5β-cholestane-3α-O-(β-D-glucopyranosid) uronic acid, and the minor metabolite was the glucurono conjugate of 26, 27-dinor-5β-cholestane-3α, 7α, 12α, 24β-tetrol. The results indicated that in rat liver these C₂₅- and C₂₆-bile alcohols, in contrast to C₂₇-bile alcohols, were not converted into bile acids, and that the glucuronide production became necessary for hepatic elimination of the accumulated bile alcohols.