The formation and metabolism of a naturally occurring C27 bile acid, 3α,7α-dihydroxy-5β-cholestan-26-oic acid, was studied in patients with T-tube bile fistulas. C-26-cholesterol-14C was shown to be converted to this C27 bile acid. After synthesis and labeling with tritium, 3α,7α-dihydroxy-5β-cholestan-26-oic acid was efficiently metabolized to chenodeoxycholic acid. After oral and i.v. administration there was conversion of about 80% of the administered amount to chenodeoxycholic acid. A small amount, less than 2% of the administered radioactivity, was converted to cholic acid. The remainder of the radioactivity was excreted in two unidentified peaks of radioactivity.
Russell F. Hanson