title: Tumor induction by carcinogenic agents in anuran amphibian Rana temporaria.
abstract: Effects of 12 chemical cancerogenic agents have been studied in 910 anuran amphibia of the grass frog Rana temporaria. Tumors developed by administration of 8 of the agents studied. Dimethyl, diethyl and dibutylnitrosamines dissolved in water induced tumors in 44.2, 43.6 and 50% of animals, respectively; benzidine and 2-acetylaminofluorene administered subcutaneously and per os--in 46.6 and 41.2%, respectively, whereas p-dimethylaminoazobenzene and orthoaminoazotoluene (per os and subcutaneously)-in 30--33.3% of cases. Diethylstilbestrol-propionate induced tumors in 21% of cases. All the tumors developed within relatively short periods of time (15.6--31.9 weeks) and were located in the liver (hepatocellular cancer, hepatoadenomas) and the haemopoetic system (hemocytoblastosis). In control group of animals 3 amphibia developed multiple tumors of skin-cystadenopapillomas. The results obtained testify to the common mechanism of cancerogenesis in classes of vertebrates. In addition, the findings presented indicate to the suitability of amphibia as a new experimental object in oncology as well as to the applicability of these animals for purposes of express diagnostics of cancerogenicity. It may successfully serve as a biological indicator of environmental pollution with blastomogenic agents.
mesh_terms: D000818:Animals; D001554:Benzene; D002273:Carcinogens; D004054:Diethylstilbestrol; D005260:Female; D005399:Fishes; D005449:Fluorenes; D008297:Male; D009374:Neoplasms, Experimental / Q000139:chemically induced*; D009602:Nitrosamines; D011896:Rana temporaria; D012621:Seasons
chemical_list: D002273:Carcinogens; D005449:Fluorenes; D009602:Nitrosamines; D004054:Diethylstilbestrol; D001554:Benzene