Potential transmission of the cytogenetic effects of cisplatin in the malegermline cells of Swiss mice

Cisplatin (CP) (in Oncoplatin), a widely used drug in cancer chemotherapy, and cyclophosphamide (CY) (in Endoxan), another anticancer drug, were inves tigated as the test chemical and positive control, respectively, for their cytogenetic effects on spermatogonia of mice at 24 hours post-treatment aft er a single exposure. The different doses of the chemicals tested were CP 2 , 3, 5 mg/kg and CY 40 mg/kg b.w. of mice. Each of the doses of CP induced a significant number of chromosomal aberrations, mostly chromatid breaks an d fragments. The potential transmission of such cytogenetic effects of the chemicals from spermatogonia to spermatocytes was assessed at week 4 post-t reatment from the primary spermatocytes, which showed a significant number of aberrant spermatocytes with atypical bivalents viz. spermatocytes with a utosomal and/or XY univalents, tetravalents and with extra elements. The pr obable causes of the formation of univalents and tetravalents are discussed . The transmission of the cytogenetic effects of the chemicals from spermat ogonia up to sperm was assessed at week 8 post-treatment from the morpholog y of sperm collected from vas. Quantitatively the transmission of such effe cts was found decreased substantially by the time the exposed spermatogonia became sperm. Still there was the occurrence of a few abnormal sperm at we ek 8 post-treatment. The probable causes of the quantitative decrease in th e transmission of the effects from spermtogonia to sperm are discussed.