title: [Dynamics of the frequencies of sister chromatid exchange and chromosome aberrations in vivo].
abstract: 2.4 and 6 mg/kg thiophosphamide (T) was administered intravenously to New Zealand rabbits. A decrease in sister chromatid exchange (SCE) and chromosome aberration (CA) rate began immediately after the mutagenic action of T was over. The expected SCE rate was more than the investigated one. The difference between expected and investigated SCE rate increased with the dose of T. A calculation of SCE was based on the amount of the administered T, the rate of T removal and cell sensitivity to T. The death of cells with high number of SCE resulted in a fast decrease in SCE rate in the first 4 days. Reparative processes and cell proliferation in lymphocyte tissue resulted in a slow decrease in SCE rate after the 4th day. A number of nuclear cells in the blood was the smallest on the 4 th day, at the same time relative increase in CA rate was observed. The time of sampling and the dose of the substance tested should be taken into account for a more accurate estimation of mutagenic activity of some chemicals in in vivo cytogenetic tests.
mesh_terms: D000818:Animals; D002869:Chromosome Aberrations; D004305:Dose-Response Relationship, Drug; D008677:Metaphase / Q000187:drug effects; D009152:Mutagenicity Tests / Q000379:methods; D011817:Rabbits; D012854:Sister Chromatid Exchange / Q000187:drug effects; D013852:Thiotepa / Q000633:toxicity; D013997:Time Factors
chemical_list: D013852:Thiotepa
vernacular_title: Dinamika chastot sestrinskogo khromatidnogo obmena i aberratsiĭ khromosom in vivo.