- The mutagenicity and cytotoxicity of cis-diamminedichloroplatinum (II) (cisplatin) at doses of 5, 10 and 20 micrograms/ml in Chinese hamster ovary (CHO) cells have been examined. A morphological characterization of several cell types induced by cisplatin was carried out. The frequencies of both cells with micronuclei and binucleate cells as a time-dependent parameter have also been studied. Whilst the number of cells with micronuclei was found to decrease with time, the number of binucleate cells increased. The possible kinetic mechanism for the production of binucleate cells and cells with micronuclei is discussed. A morphometric analysis was also performed. The nuclear area in both treated and control nuclei was measured with the IBAS image analysis system. The results of this analysis show that a continuous reduction in the nuclear size in the control cells is produced. However the size of the treated cells increased after treatment.