Bile acids. XXXIX. Metabolism of 5α-cholestane-3β,26-diol and 5α-cholestane-3β,7α,26-triol in the rat with a bile fistula

Abstract

25r-5α-[5α,6α-3H2]Cholestane-3β,7α,26-triol was prepared from 3β,26-diacetoxy-5α[5α,6α-3H2]cholestan-7-one that was obtained from kryptogenin. Huang-Minlon reduction of the ketone provided 25r-5α-[5α-3H]cholestane-3β,26-diol. Results from mass spectrometry, molecular rotation, and several types of chromatography are consonant with the assigned structures. Bile was collected for 8 days from adult male rats, with cannulated bile ducts, that had received approximately 0.8 mg of the triol or diol intraperitoneally. Bile from the first 12 hr was hydrolyzed, and the bile acids were separated by partition chromatography. The chromatographic pattern of separated bile acids was much simpler for the triol than the diol. Approximately 50% of the bile acids derived from the triol were trihydroxy allo acids (allocholic acid, 44%, and its 3β isomer, 5.3%); only 16.4% allocholic acid was obtained from the diol. Comparable amounts of allochenodeoxycholic acid were derived from the diol and triol (21.2% and 28.2%, respectively). Unidentified metabolites in the dihydroxy acid fraction derived from the diol constitute 15.8% of chromatographed material.

Keywords

• 25r-5α-[5α,6α-3H2]cholestane-3β,7α,26-triol
• 25r-5α-[5α-3H]cholestane-3β,26-diol
• allocholic acid
• allochenodeoxycholic acid
• 3β-hydroxy allo bile acids
• kryptogenin