The primary rat hepatocyte micronucleus assay: general features

Recent advances in cell culture have allowed proliferation of primary rat hepatocytes enabling the analysis of different cytogenetic endpoints such as sister chromatid exchanges (SCE), chromosomal aberrations and micronuclei. The latter are of particular interest as preparation, staining and analysis is less time-consuming than the analysis of chromosomal aberrations and SCE what makes micronuclei an attractive short-term assay. This paper gives (1) a summary of the specific features of primary hepatocytes including ploidy, nuclearity and multipolar mitoses, (2) a summary of the culture conditions for proliferation and the proliferation kinetics, (3) an experimentally based interpretation of the comparatively high background levels of cells with micronuclei, and (4) an experiment-based discussion of approaches to circumvent the major disadvantage: the cytochalasin B method cannot be applied due to the high percentage of binucleated cells.