New approaches to mutagenicity studies in animals for carcinogenic and mutagenic agents. II. Clastogenic effects determined in transplacentally treated mouse embryos.
Cell suspensions from whole embryos were obtained on the 12th day of gestation from treated pregnant female mice. For the present experiments five model mutagens-BaP, bleomycin, mitomycin C, procarbazine, and TEM--were chosen for their different modes of action in inducing chromosomal aberrations. Time-response and dose-response were studied for chromosomal aberrations induced by transplacental treatment of mouse embryos. All five known mutagens gave a positive response in the present system. The maximum time of response varied from compound to compound and was found as early as 3h after treatment with the G2-clastogen bleomycin or as late as 18 h after treatment with the bifunctional alkylating agent TEM. Chromatid breaks and exchanges increased with dose in all instances. The correlations between clastogenic, carcinogenic, and teratogenic effects are discussed. It is concluded that the transplacental cytogenetic test may be applicable to identify chemicals that exhibit all three properties.
D000818:Animals; D001564:Benzo(a)pyrene; D001580:Benzopyrenes / Q000633:toxicity; D001761:Bleomycin / Q000633:toxicity; D002869:Chromosome Aberrations; D004622:Embryo, Mammalian / Q000187:drug effects*; D005260:Female; D005865:Gestational Age; D008431:Maternal-Fetal Exchange; D051379:Mice; D016685:Mitomycin; D008937:Mitomycins / Q000633:toxicity; D009152:Mutagenicity Tests / Q000379:methods*; D011247:Pregnancy; D011344:Procarbazine / Q000633:toxicity; D014265:Triethylenemelamine / Q000633:toxicity
D001580:Benzopyrenes; D008937:Mitomycins; D001761:Bleomycin; D001564:Benzo(a)pyrene; D011344:Procarbazine; D016685:Mitomycin; D014265:Triethylenemelamine