Long-term maintenance of monoxygenase activities in cultured fetal rat hepatocytes.

Fetal hepatocytes cultured in the presence of dexamethasone even in low concentration were maintained alive for several weeks. The expression of monoxygenase in these cells is switched from fetal to adult type. Their aldrin epoxidase and ethoxycoumarin-o-de-ethylase activities were maintained at a high level. Cytochrome P-450 concentration remains stable in these cells throughout the culture period. Cell-cell and cell-biomatrix interactions seem to play an important role in the control of growth, maturation and enzymatic activity expression of the cells in culture. This model may constitute an interesting approach for the study of drug metabolism and drug toxicity in vitro.