Mechanisms of reparative regeneration of rat testis after injection of paclitaxel.

Population of spermatogonia was reduced in 2, 3, and 6 months after single intravenous injection of antitumor drug paclitaxel in maximum tolerated dose (MTD). The count of Sertoli cell increased in 3 months after the start of the experiment. The maturity of the seminiferous tubule epithelium was lower than in intact rats. Spermatogenesis productivity did not differ from that in intact animals 6 months after start of the experiment. These data indicate that regeneration of the spermatogenous tissue after paclitaxel treatment is realized via renewal of the spermatogenic epithelium, but considering the amount of spermatogonial cell population, the recovery rate would be low.