Epididymal response to exogenous testosterone in rats sterilized neonatally by estrogen.

Male rats treated with estradiol dipropionate (250 mug) by subcutaneous injection on Day 5 of postnatal life failed to show maturation changes in the testis and epididymis at puberty. Histological examination at 60 days revealed inhibition of spermatogenesis at primary spermatocyte stage and atrophic Leydig cells. Epididymis presented infantile features and there was a marked reduction in the secretory activity as revealed by lowered concentration of sialic acid and glycerylphosphorylcholine. Testosterone therapy (1 mg/day) for a period 45 days prior to autopsy at 60 days failed to induce completion of spermatogenesis but restored the structural and functional integrity of the epididymis.