Target Organs for Testosterone Transferred from Vein to Artery in the Pampiniform Plexus: The Epididymis

During infusion of testosterone-3 H into the pampiniform plexus of 8 anesthetized rats, radioactivity in blood from the testicular artery was more than 4 times that in systemic arterial blood. During the same infusion period, radioactivity in epididymal artery blood remained similar to systemic artery blood levels. Endogenous testosterone levels in epididymal artery blood from 9 additional rats did not differ from systemic artery blood levels. We concluded that testosterone transferred from spermatic vein to artery in the pampiniform plexus enters the arterial supply distal to the origin of the epididymal arteries and cannot therefore enter the epididymis by this route