N-Nitrosodiethylamine genotoxicity in primary rat hepatocytes: Effects of cytochrome P450 induction by phenobarbital

► N-Nitrosodiethylamine (NDEA)-induced genotoxicity and cytotoxicity in the presence of phenobarbital (PB). ► PB prior to NDEA treatment decreases the number of micronucleated cells. ► NDEA induces an increased in the number of chromosomal aberrations after pre-treatment with PB. ► NDEA-treatment induced synergistic effect in the expression of the CYP2B1 and CYP2B2 mRNA. ► Alterations of CYP expression by PB increased the cytotoxicity and genotoxicity of NDEA leading to the final genotoxic metabolite.