%0 Journal Article %A H Mukhtar %A D R Bickers %T Drug metabolism in skin. Comparative activity of the mixed-function oxidases, epoxide hydratase, and glutathione S-transferase in liver and skin of the neonatal rat. %D 1981 %J Drug Metabolism and Disposition %P 311-314 %V 9 %N 4 %X Aryl hydrocarbon hydroxylase (AHH) activity in the skin of neonatal rats was compared to that in epidermis, dermis, and other body tissues. Following topical application of benzo[a]pyrene (BP) or the polychlorinated biphenyl mixture Aroclor 1254 there was induction of AHH in each tissue studied. There was a greater increase in the activity of skin enzyme as compared to other extrahepatic tissues. When whole-organ activity (pmol of 3-OH-BP per min per whole organ) was considered, skin represented 2%, 21%, and 27% or whole body activity in control, BP-treated, and Aroclor 1254-treated animals, respectively. Skin microsomes from control rats exhibited 2, 0.5, 24, and 6% of corresponding liver microsomal AHH, 7-ethoxycoumarin de-ethylase, NADPH-cytochrome c reductase, and epoxide hydratase activities, respectively. Glutathione S-transferase activity in skin cytosol was 15% of the corresponding hepatic activity. Following topical application of Aroclor 1254 there were increases in the activity of AHH and 7-ethoxycoumarin de-ethylase in the skin and the liver. Glutathione S-transferase (40-60%) and epoxide hydratase (83-94%) activities in neonatal rat liver were induced by skin application of Aroclor 1254. %U https://dmd.aspetjournals.org/content/dmd/9/4/311.full.pdf