Biochemical studies of isolated rat hepatocytes from normal and phenobarbital-treated liver as obtained by rate zonal centrifugation.

Cell suspensions from normal and phenobarbital treated livers were analysed by rate zonal centrifugation in ficoll gradients. No difference in the microsomal cytochrome P-450 and NADPH-cytochrome C reductase content and in the incorporation rate of radioactive leucine was noted between light and heavy hepatocytes. After centrifugation of a mixture of radioactive phenobarbital-treated cells and normal liver cells, the specific radioactivity was constant, indicating that the hepatocytes from drug-treated liver had the same density as the normal cells.