Transplantable tumor lines generated in clonal zebrafish.

Transplantable zebrafish tumors are a novel and very promising model in cancer research. However, further progress in this field has been contained by a lack of true inbred lines in zebrafish. To overcome this problem, we generated two lines of homozygous diploid clonal zebrafish lines (i.

Carcinogenic effect of N-nitrosodimethylamine on diploid and triploid zebrafish (Danio rerio).

Viability of polyploid organisms in lower vertebrates including fish provides an additional tool to investigate genetic mechanisms of neoplastic transformation caused by carcinogens. Here we present data on differential sensitivity of diploid and triploid zebrafish (Danio rerio) to N-nitrosodimethylamine (NDMA) induced hepatocarcinogenesis. The effect of the carcinogen was studied in 100 diploid and 120 triploid zebrafish.

The study of mutagenic activity of carcinogens and other chemical agents with Salmonella typhimurium assays: testing of 126 compounds.

126 chemical compounds were tested in the Ames assay with bacterial Salmonella typhimurium of 8 various strains (mainly TA 98 & TA100). For metabolic activation liver S9 from arochlortreated rats was used. In the first group of substances tested (51 compounds with confirmed carcinogenicity for animals) 45 agents possessed mutagenicity and 6 gave false-negative response (1.

Dysplastic lesions and abnormalities in amphibians associated with environmental conditions.

High incidence of developmental anomaly and tumor-like dysplasia of osteochondrous tissue of hind limbs has been detected in frogs and toads the larval development of which has taken place in water, contaminated with sewage. Correlation between frequency of dysplasia and the level of water oxidation has been noted. Study on histogenesis of the marked tumor-like dysplasia were performed.

On spontaneous skin tumours in amphibia.

In 7 from 320 Rana temporaria grass frogs and 16 from 978 Rana ridibunda pond frogs, the 31 and 47 spontaneous skin tumors respectively, were observed. The tumors were represented by cystadenopapillomas and adenocarcinomas, and developed from epithelium of skin mucous glands. The spontaneous pigment tumors (melanophoromas) were found in 2 axolotls Ambistoma mexicanum.