Abstract
Hepatoma cells derived from the Reuber H35 rat hepatoma express cytochrome P450 enzymes of two major families: polycyclic aromatic hydrocarbon‐inducible forms are found in both differentiated and dedifferentiated cells while phenobarbital (PB)‐inducible forms are found only in differentiated cells. We report here that (i) benzanthracene and PB induce P450 c mRNA in differentiated and dedifferentiated cells and (ii) dexamethasone and PB induce P450 b/e and/or P450 PB1 mRNAs in differentiated cells but not in dedifferentiated cells.