Effect of FSH and testosterone propionate on spermatogenesis in immature rats treated with clomiphene

Abstract

The effects of testosterone propionate (TP) and follicle-stimulating hormone (FSH) on the completion of the first wave of spermatogenesis in rats treated with clomiphene are reported. Clomiphene in doses of 250 μg/day beginning on day 22 inhibits spermatogenesis at the primary spermatocyte stage. Treatment of clomiphene-fed rats with small doses of TP (200 μg/day) advanced spermatogenesis to the early spermatid stage (step 7), while follicle-stimulating hormone (FSH, 75 μg/day) had no appreciable effect on the completion of spermiogenesis. However, a combined treatment of the two hormones synergized at these dose levels to advance spermatogenesis to completion within 30 days of the initiation of treatment. The dose of TP (200 μg/day alone) which inhibits pituitary gonadotropins in immature rats is ineffective in advancing spermatogenesis, while in clomiphene-fed rats a high dose of TP (0.5 or 1 mg/day) by itself facilitates the progress of spermatogenesis to completion. Testicular weights were restored to normal levels only by treatment of clomiphenefed rats with a synergistic dose of 75 μg/day of FSH and 1 mg/day of TP. These results are discussed in relation to the role of gonadotropic hormones and androgen in the initiation and maintenance of testicular function.