TESTICULAR DEVELOPMENT IN RATS TREATED WITH SEVERAL STEROIDS SHORTLY AFTER BIRTH

Abstract

Summary. One-day-old male rats received a single injection of oestradiol benzoate, testosterone propionate or one of three testosterone derivatives in order to study their action on testicular development, particularly spermatogenesis. All substances caused a delay of spermatogenesis, observed when rats were killed at 35 or 60 days of age. These effects were reversible and testis histology as well as fertility were restored by the time the animals were 90 days old. Seminal vesicles at 90 days were under-developed in all but oestrogen-treated rats which may indicate impairment of icsh liberation. Testicular growth is more powerfully inhibited by drugs bearing hydroxylated instead of oxygenated C3. The combinations of C3—OH and C17 = 0 give stronger inhibition than any other.