[Influence of intratesticular injections of tamoxifen on spermatogenesis and testosterone secretion in the rat]. / Wplyw dojadrowego podawania tamoksyfenu na spermatogeneze i wydzielanie testosteronu u szczura.

Three groups of adult Wistar rats were injected every second day with: 5 or 10 or 20 micrograms of tamoxifen (Tx) to the right testis. Left testis was injected with the same volume of solvent. Control group received the solvent for Tx. Animals were killed after 15 days. Blood samples were taken from heart for testosterone determinations. Both testes were taken for histological examination and quantitative analysis of seminiferous epithelium was performed. Testosterone was analysed with radioimmunoassay method. It was demonstrated that intratesticular supply of Tx caused significant rise in the number of type A spermatogonia and significant increase of testosterone concentration in the blood. It is concluded that Tx influences spermatogenesis in adult rats through stimulation of the earliest steps of gamete formation. Testosterone may or may not mediate this effect.

[Tamoxifen and spermatogenesis in rats subjected to effects of estradiol]. / Tamoksyfen a spermatogeneza u szczurów poddanych dzialaniu estradiolu.

During 14 subsequent days male Wistar rats received subcutaneously 50 micrograms of EB and different doses of tamoxifen intratesticularly. Action of EB was examined by comparison with the group, which received the solvent for EB only. EB caused the reduction in the mean testis weight, degenerative changes of germinal cells and decrease of blood testosterone level to undetectable values. Tamoxifen did not prevent these changes, but revealed a positive influence on the mean numbers of spermatogonia, spermatocytes and spermatids, including spermatozoa. It indicates that tamoxifen may stimulate the whole spermatogenesis in spite of the inhibition of testosterone production.