Studies with Androsterone-3-3H,4-14C

The metabolic disposition of androsterone-3-3H,4-14C in 2 subjects has been studied. Dehydrogenation of the C-3 hydroxyl group with resynthesis of androsterone was quite extensive. Part of the androsterone that was retained in the body for a longer term lost as much as 80% of the isotope initially at C-3. Much of this tritium appeared promptly in the body water and the isotope continued to accumulate throughout the study. Recovery of the carbon skeleton was less complete and virtually all the 14C was present as androsterone. Elimination was almost exclusively by way of the urine; feces contained only small amounts of the administered 14C. Declining 3H/14C ratio of androsterone with time suggested a continuous process of oxidation of the 3α-hydroxyl group and resynthesis by reduction with protium. There was a difference in isotope ratio between androsterone conjugated as “glucosiduronate” and “sulfate.” The study demonstrates the surprising extent to which an important biologically active hormone ...