Ouabain resistance assay

Matthews EJ, DelBalzo T, Rundell JO. 1985. Assays for morphological transformation and mutation to ouabain resistance of Balb/c-3T3 cells in culture. In Ashby J, de Serres FJ, et al., eds. 

Marayama, H., Tanaka, T. Williams, GM. (1990) Effects of the peroxisome proliferator di(2-ethylhexyl)phthalate on enzymes in rat liver and on carcinogen-induced liver altered foci in comparison to the promoter phenobarbital Toxicol. Pathol., 18, 257-267 Matsushima, T, Muramatsu, M. Haresaku, M. (1985) Mutation tests on Salmonella typhimurium by the preincubation method. Prog. Mutat. Res., 5, 181-186 Matthews, E.J., DelBalzo, T. Rundell, J.O. (1985) Assays for morphological transformation and mutation to ouabain resistance of Balb/c-3T3 cells in culture. Prog. Mutat. Res., 5, 639-650... 

Kuroki, T. Munakata, K. (1985) Assays for the induction of mutations to ouabain resistance in V79 Chinese hamster cells in culture with cell- or microsome-mediated metabolic activation. Prog. Mutat. Res., 5, 543-545... 

Aflatoxin Bg is a potent mutagen toward 5. typhimurium in the presence of rat liver homogenate. Liver cells or fibroblasts derived from rats have also been used as feeder layers for Chinese hamster V79 cells. Mutation to ouabain-resistant cells was found to occur only in the presence of liver cells. Fibroblast cells were incapable of metabolizing AfBj (286). Studies on the mutagenic activity of related aflatoxins have not employed the sophisticated biochemical systems which have recently been studied. The use, for example, of duck liver homogenate in the metabolic activation of AfBg may result in enhanced mutagenic potential compared to use of rat liver. Incorporation of the advances in the biochemical studies on aflatoxin metabolism to in vitro assay systems can be expected in the near future. 

DNA single-strand break frequency was measured by alkaline elution [16] and sister chromatid exchanges (SCEs) were assayed by the method described by Wolff [32]. Hypoxanthine-guanine phosphoribosyl transferase (HPRT 6-thioguanine) and Na/K ATPase (ouabain) resistant mutants of CHO were determined by the methods described by Cleaver [7]. Repair replication after MMS treatment was measured in isopycnic gradients [8]. 

Gamer, R.C. Campbell, J. (1985) Tests for the induction of mutations to ouabain or 6-thio-guanine resistance in mouse lymphoma L5178Y cells. In Ashby, J., de Series, F.J., Draper, M., Ishidate, M., Jr, Margolin, B.H., Maher, B.E. Shelby, M.D., eds, Progress in Mutation Research, Volume 5, Evaluation of Short-Term Tests for Carcinogens. Report of the International Programme on Chemical Safety s Collaborative Study on in vitro assays, Amsterdam, Elsevier Science, pp. 525-529... 

A central question concerning the use of a particular locus to measure chemically induced mutation is whether that particular locus is representative of other loci. The ability of the lymphoblast line HH-4, a WI-L2 subclone, to form colonies in the absence of a feeder layer enabled us to isolate clonal lines that are heterozygous for TK and to develop a mutation assay based on loss of TK. We have also been able to develop an assay based on ouabain (OU) resistance. We have now begun to compare induced mutant frequencies at the tk, hgprt, and Na /K ATPase loci. 

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