METABOLISM OF 4-C14-TESTOSTERONE IN HUMAN SUBJECTS III. FATE OF ANDROSTERONE AND ETIOCHOLANOLONE*

C14-androsterone and C14-etiocholanolone were administered intravenously to 7 human female subjects; 3 received both steroids, and 4 (with bile fistulas) received only one. The radioactivity was excreted in the urine almost quantitatively in a few hours. The unconjugated steroids were cleared from the plasma rapidly, with a half-life of twenty minutes. The level of the glueuronidate fraction of the plasma was approximately ten times higher than that of the unconjugated fraction. The glucuronidates after administration of etiocholanolone were cleared faster than after administration of androsterone. Androsterone and etiocholanolone are not excreted in the bile in appreciable quantities; in 3 of the 4 bile-fistula subjects negligible amounts of radioactivity were recovered. Moreover, after administration of 4-C14-testosterone, no androsterone and only a small amount of etiocholanolone was recovered from the bile. This last observation is tempered by the fact that most of the radioactivity in bile is not extractable after hydrolysis. The results arc discussed in relation to the metabolism of C14-testosterone.