Quantitative Evaluation of Primordial Follicles in Rat Ovaries during the Early and Delayed Terms after Different Cytostatic Exposures.

Experiments on female Wistar rats showed that cytostatic agents (farmorubicin, platidiam, carboplatin, and etoposide) induce an initial significant decrease in the number of primordial follicles. Over the next 2-3 estrous cycles after administration of farmorubicin, platidiam, and carboplatin, this index practically did not differ from the control. The number of primordial follicles in the third and fourth estrous cycles after farmorubicin administration, as well as in the second and sixth estrous cycles after etoposide administration was much higher than the follicular reserve after cytostatic treatment (first estrous cycle). The ovarian reserve was exhausted in the delayed period after the start of the experiment. This dynamics of the pool of primordial follicles suggests that the ovary of rats in the postnatal period of life contains a limited number of female germline stem cells.