Characteristics of rat hepatocytes sorted by fluorescence-activated flow cytometry. Effects of mixed function oxidase inducers.

Fluorescence-activated flow cytometry has been used to separate rat liver parenchymal cells into five equal computer-generated regions on the basis of their mixed function activities towards diethoxyfluorescein. Enzymic activities in the sorted fractions showed 2.3-2.9-fold enrichment of 3-cyano-7-ethoxycoumarin O-deethylase, lactate dehydrogenase and pyruvate kinase activities in the cells of region 5. Cytochrome P-450 PBla and glutamine synthase activities were enriched 1.8- and 7-fold respectively in region 2 hepatocytes. Pretreatment of rats with phenobarbitone or 3-methylcholanthrene did not change the pattern of enrichment with respect to monooxygenase or lactate dehydrogenase activities. However, cytochrome P-450 PB3a and MC1a respectively were concentrated in the cells from region 5. In contrast, ethoxyquin caused enrichment of cytochrome P-450 in the hepatocytes in region 2. This fraction also contained the highest percentage of gamma-glutamyltranspeptidase positive cells.