Induction of intestinal microsomal enzymes by polycyclic aromatic hydrocarbons

1. The efficacy of induction of intestinal microsomal aryl hydrocarbon hydroxylase (AHH), 7-ethoxyresorufin o-deethylase and cytochrome P-450 by various polycyclic aromatic hydrocarbons were studied. 2. The greatest induction of the specific MFO activities tested was produced by 2,3,7,8-tetra-chlorodibenzo-p-dioxin (TCDD) with 3-methyl-cholanthrene (MC) a close second. 3. Rank order of efficacy of induction of spectrally determined cytochrome P-450 was 2,3,7,8-tetra-chlorodibenzo-p-dioxin (TCDD), Arochlor 1254 (ARO), 3-methylcholanthrene (MC) and benz(a)anthracene(BA). 4. No unique protein peaks were found when the sodium dodecyl sulfate-polyacrylamide gel electrophoresis of MC treated intestinal microsomes were prepared.