The presence of metabolites of 3-H-testosterone in the lumen of the cauda epididymidis of the rat.

Following the administration of 3-H-testosterone to adult male rats radioactivity appeared in epididymal fluid and at 60 minutes was in excess of the level in tissue of the cauda epididymidis and blood plasma. Ligation of the arterial blood supply to this region caused a significant decline in the radioactive content of epididymal fluid and cauda tissue. It is concluded that direct transfer occurs from the systemic circulation into the cells of the cauda epididymidis and thence into the lumen of the duct. The major radiometabolite of 3-H-testosterone identified in chloroform extracts of epididymal tissue (60.6%) and epididymal fluid (72.8%) was 17-beta-hydroxy-5-alpha-androstan-3-one.