[The effect of chemical mutagens on mammalian spermatogenesis. A quantitative evaluation].

A quantitative analysis of spermatogenesis in mice and rats has shown that the response of various germ cells to cytotoxic effects of Dipin or NMU differs. The spermatogonial compartment consisting of actively proliferating cells and some stem cells are the main targets for these drugs. The advanced I order spermatocytes, spermatids and spermatozoa proved to be less susceptible.

[The modifying cytogenetic effects of gossypol and its derivatives].

The method of micronuclei account allowed to demonstrate protective effect of gossypol and its derivatives megacin and batriden of chromosomes of rat male germ cells from mutagenic effect of nitrosomethylurea (NMU) and, conversely, enhancement of clastogenic effect of another alkylating agent, fotrin. Strong antimutagenic effect of gossypol from NMU was also observed in external granular layer of young rat cerebellum. Possible mechanisms of antimutagenic action of this unique polyphenol of cotton plant are discussed.

[The effect of chemical mutagens on mammalian spermatogenesis. A cytogenetic analysis].

It was shown using the micronucleus test and estimating the defects of sperm heads that premeiotic and meiotic mammalian cells are genetically very sensitive to Dipin and nitrosomethylurea. In rats, unlike mice, the stem and differentiating spermatogonia with serious chromosomal defects are not eliminated and pass through a "sieve" of mitotic and meiotic divisions reaching the stage of round spermatids. Our observations suggest long-term preservation Dipin-induced, rather than nitrosomethylurea-induced, mutations in the stem cells of both mice and rats.