Effects of mitomycin-C on spermatogenesis of mice with reference to the dose relation between mitomycin-C and X-rays.

Some of the antibiotics have excited our interest in the field of cancer chemotherapy because of their anti-tumor actions. In this connection it is of particular significance to understand the mechanism of cell-damage under the influence of these agents, since both growth and regression of the tumor are under the control of the mitotic mechanism. Mitomycin-C is one of the antibiotics isolated from Streptomyces caespitosus by WAKAKI and his co-workers (1958). Evidence has been presented by HATA and his associates (1956), SAKAI and TERANAKA (1957), WAKAKI et al. (1958), KOBAYASHI (1959, 1960), NAKANISHI and MAKINO (1962) and KIMURA (1963) that Mitomycin exerts a strong antagonistic effect on various kinds of tumors. Of particular interest are the recent findings of TANAKA (1966) and TANIMURA (1961, 1968) indicating that disturbance of sex-differentiation and malformation occur in mice treated with the agent in embryonic stages. However, knowledge of cytological and histological effects on germ cells has remained quite insufficient. The present author has aimed to investigate quantitatively and morphologically the effect of Mitomycin-C on spermatogenetic cell populations in the mouse, in order to provide some information useful for understanding the mechanism of cell-damage under the application of this agent, and further to obtain some data to be compared with those obtained by X-irradiation in the earlier studies of this author (ITAGAKI, 1962, 1966) with special reference to the dose relation between Mitomycin-C and X-rays.