Previous data indicate that the CYP2E1 gene is transcriptionally activated after birth, but that the expression of ethanol-inducible CYP2E1 protein, hereafter, is regulated by post-transcriptional mechanisms. The constitutive expression of CYP2E1 protein is restricted to the perivenous region of the liver lobule. Here we present results from in situ hybridization and run off experiments indicating that this regioselectivity is caused by a higher rate of gene transcription in the perivenous hepatocytes. We also show that transcription of the CYP2E1 gene is activated by starvation, indicating that also this P450 gene is under transcriptional control under certain physiological conditions.