Effect of 5agr Reduced Androgens on Sex Accessory Organs. Initiation and Maintenance of Spermatogenesis in the Rat

Abstract

The effect of several androgens on initiation and maintenance of spermatogenesis was studied in newborn estrogen-blocked and in adult hypophysectomized rats. The steroid treatment inhibited testicular and body weight in all animals. Treatment of estrogen-blocked animals with androgens resulted in a stimulation of the growth of sex accessory organs, except in the case of androsterone. Initiation of spermatogenesis and its progression to mid pachytene stage (first wave) was observed in all steroid treated rats. In estrogen-blocked animals the first wave of spermatogenesis proceeded only to pachytene spermatocytes. Administration of testosterone propionate, dihydrotestosterone or 5α-androstanediol to these animals resulted in completion of meiosis and formation of spermatids up to step 8 of spermiogenesis. Completion of meiosis was not observed in androsterone treated rats. In hypophysectomized animals all 5α-reduced androgens maintained spermatogenesis similar to testosterone.