Repair-Mediated Mutagenesis

San, R.H.C., Williams, G.M. 1977. Rat hepatocyte primary cell culture-mediated mutagenesis of adult rat liver epithelial cells by procarcinogens. Proc. Society Experimental Biology Medicine 156 534-38. Roberts, J.J. 1980. Cellular responses to carcinogen-induced DNA damage and the role of DNA repair. British Medical Bulletin, 36 25-31. 

The loss in viability can be greatly delayed by inclusion of corticosteroids in the medium/ thereby extending the life of the cultures. This effect may be related in part to the inhibition by corticosteroids of protease production by the cultures.Primary cultures of hepatocytes are used for DNA repair studies (Section 6) and as feeder cells for cell-mediated mutagenesis (Section 8). 

In the heptatocyte-mediated mutagenesis studies, freshly isolated hepatocytes were mixed in a ratio of about 2 1 with liver epithelial cells before inoculation into culture flasks. After attachment, the two cell types were found to be well mixed and in close contact. Exposure of mixed cultures to several activation-dependent carcinogens that produce DNA repair in hepatocytes also produced mutagenesis in the cocultivated rat liver epithelial lines (Table 7) under conditions of exposure in which the carcinogens were not mutagenic to the lines in the absence of cocultivated hepatocytes. Thus, activated metabolites produced by the hepatocytes were transferred to the epithelial cells. Efforts to simplify this assay by the use of stored frozen hepatocytes are in progress. 

The studies described in this review were performed in collaboration with many colleagues the development of the techniques for primary cultures of hepatocytes and detection of DNA repair was done with Dr. Brian A. Laishes, now at McArdle Laboratories the mutagenesis studies were the work of Dr. Jules J. Berman, now at National Cancer Institute, and Dr. Charles Tong, Naylor Dana Institute and the hepatocyte-mediated mutagenesis system was developed by Dr. Richard H. C. San, now at the University of British... 

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