Suppression of spermatogenesis without inhibition of steroidogenesis by a 1,2,3-trihydroxypropane solution

This study presents the first evidence that the non-hormonal, biological substance, 1,2,3- trihydroxypropane (THP) acts as a selective and potent antispermatogenic agent without any apparent toxic or endocrine side effects. The studies were done on 119 rats which were injected intratesticularly (50-200 microliter) with either sterile filtered distilled water (Control) or water/THP (3:7; Treated) and histological, biochemical and fertility determinations were made up to 11 weeks after the injections. The results show that within one week of a single injection with THP, the weights of testes and epididymides are significantly less than those of the Controls and the reduced weights persist for at least 11 weeks. The seminiferous tubules are largely depleted of spermatogenetic cells by 2 weeks and they remain devoid of dividing germ cells for the 11 week period. The Leydig cells have a normal appearance and histochemically show the same 3 alpha-hydroxysteroid dehydrogenase (3 alpha-HSD) and 3 beta-HSD activities as Controls. In vitro studies of the testes showed that the activities of the steroid enzymes 20 alpha-HSD, 17 beta-HSD, 17 alpha-hydroxylase and C17-20-lyase and the production of testosterone and androstenedione were not altered by the THP treatment. Similarly, serum levels of testosterone, LH, and FSH, measured by RIA, and weights of the prostate and seminal vesicles were the same as in Controls. Treated males showed the same degree of sexual behaviour and mating frequency as the Controls, but after the 3rd mating were 100% infertile for the duration of the experiments. The total number of sperm in epididymides of Treated rats was reduced by 99.99% after the 3rd mating.(ABSTRACT TRUNCATED AT 250 WORDS)