Induction of monooxygenase activity in the intestine of spot (Leiostomus xanthurus) , a marine teleost, by dietary polycyclic aromatic hydrocarbons
van Veld, P.A.; Stegeman, J.J.; Woodin, B.R.; Patton, J.S.; Lee, R.F.
Drug Metabolism and Disposition the Biological Fate of Chemicals 16(5): 659-665
1988
ISSN/ISBN: 0090-9556 PMID: 2906586 Document Number: 306672
The response of intestinal monooxygenases to dietary polycyclic aromatic hydrocarbon (PAH) exposure was evaluated in spot (Leiostomus xanthurus), a marine teleost fish. Ethoxyresorufin O-deethylase (EROD) and aryl hydrocarbon hydroxylase (AHH) activities were highest in the pyloric caeca and in the proximal half of the intestine. Intestinal microsomes from fish given control diets had very low levels of EROD and AHH activities relative to those in liver. After exposure to a diet containing 10 mg of 3-methylcholanthrene/kg of food, the levels of intestinal EROD and AHH activities increased 36-fold and 17-fold, respectively, such that intestinal monooxygenase activity exceeded that of the liver, which was not induced by this treatment. A significant increase in intestinal monooxygenase activity occurred in fish receiving dietary benzo recognized a single protein band in intestinal microsomes, with Mr near 54,000, which we conclude is the spot counterpart to cytochrome P-450E. The presence and activity of PAH-inducible cytochrome P-450 of spot intestine appeared to be almost entirely dependent upon dietary PAH exposure.