RT Journal Article SR Electronic T1 STUDIES ON THE BIOTRANSFORMATION OF NAPHTHALENE-1,2-OXIDE IN FETAL AND PLACENTAL TISSUES OF HUMANS AND MONKEYS JF Drug Metabolism and Disposition JO Drug Metab Dispos FD American Society for Pharmacology and Experimental Therapeutics SP 380 OP 385 VO 2 IS 4 A1 M. R. JUCHAU A1 M. J. NAMKUNG YR 1974 UL http://dmd.aspetjournals.org/content/2/4/380.abstract AB Investigations of fetal and placental tissues from monkeys and humans indicated that enzymes were present which could catalyze the conversion of naphthalene-1,2-oxide to the corresponding diol. Each of the tissues also exhibited measurable dihydrodiol dehydrogenase and glutathione S-epoxide transferase activities. Specific activities for epoxide hydrase were far lower in placental tissues than any of the other fetal tissues studied and also did not correlate with specific activities of aryl hydrocarbon hydroxylase. Human placentas from early gestation (10-18 weeks) displayed approximately 2-fold higher epoxide hydrase activities than those investigated at term. Hydroxylation of naphthalene could not be detected in human term placentas which exhibited aryl hydrocarbon hydroxylase activities of the same magnitude as those observed in adult rat livers. The human fetal kidney appeared to possess an unusually active epoxide hydrase system. Dihydrodiol dehydrogenase and glutathione S-epoxide transferase activities were higher in soluble fractions from most of the primate fetal tissues than in corresponding preparations from adult rat livers. Copyright © 1974 by The American Society for Pharmacology and Experimental Therapeutics