RT Journal Article SR Electronic T1 Strain differences in adrenal xenobiotic metabolism in guinea pigs. JF Drug Metabolism and Disposition JO Drug Metab Dispos FD American Society for Pharmacology and Experimental Therapeutics SP 270 OP 273 VO 7 IS 5 A1 H D Colby A1 R C Rumbaugh A1 M L Marquess A1 P B Johnson A1 M R Pope A1 R E Stitzel YR 1979 UL http://dmd.aspetjournals.org/content/7/5/270.abstract AB Studies were carried out to compare adrenal and hepatic xenobiotic metabolism in various strains of guinea pigs. In all strains studied (Hartley, English Short Hair, NIH, Strain 2, Strain 13), microsomal protein and cytochrome P-450 levels and NADPH-cytochrome c reductase activities were greater in adrenals than livers. Neither adrenal values nor hepatic values for these parameters differed across strains. Ethylmorphine (EM) demethylase and benzo[a]pyrene (BP) hydroxylase activities were also greater in adrenals than livers in all strains. However, the rates of adrenal xenobiotic metabolism were far greater in the highly inbred Strain 2 and Strain 13 guinea pigs than in other strains. In contrast, hepatic metabolism of EM and BP was not strain-dependent. Adrenal steroid 21-hydroxylase activity was also similar in all strains. The results indicate that strain is an important determinant of adrenal but not hepatic xenobiotic metabolism in the guinea pig. In addition, genetic control of adrenal microsomal drug and steroid metabolism appear to be independent of one another.