| Abstract: | The dose and schedule dependent resistance occurred at the 17th (L1210/D1) and 27th (L1210/D2) generations during leukemia L1210 transplantation by the cells treated with suboptimal diazane doses. With growth of the resistance to diazane the selection of modal cell class with 39 chromosomes took place while in the parent leukemia line the modal cell class consists of the cells with 40 chromosomes. No reliable differences were observed in G-banded karyotypes between the resistant subline L1210/D1 and the parent line L1210. When the resistant sublines were transplanted without supporting the diazane doses no restoration of the leukemic cells sensitivity to the drug was observed (the time of observation for L1210/D1 was 92 transplantation generations and for L1210/D2-48 generations). The changed number chromosome characteristics remained the same in this case. |
