Identification of in vitro cytochrome P450 modulators to detect induction by prototype inducers in the mallard duckling ( Anas platyrhynchos),10.1016/

Identification of in vitro cytochrome P450 modulators to detect induction by prototype inducers in the mallard duckling ( Anas platyrhynchos)


	BibTex \| RIS \| RefWorks Download

, ,

Seven modulators of mammalian monooxygenase activity were screened for their ability to selectively stimulate or inhibit in vitro monooxygenase activities of hepatic microsomes from mallard ducklings treated with phenobarbital, β-naphthoflavone, 3,3′,4,4′,5-pentachlorobiphenyl or vehicle. Microsomes were assayed fluorometrically for four monooxygenases: benzyloxy-, ethoxy-, methoxy-, and pentoxyresorufin-O-dealkylase, in combination with each of the seven modulators. Four combinations: α-naphthoflavone and 2-methylbenzimidazole with benzyloxyresorufin, and Proadifen with methoxy- and ethoxyresorufin, respectively, were evaluated further. β-Naphthoflavone-treated groups were clearly distinguished from the corn oil vehicle control group by all of the assays and by the effects of the modulators in three of the four assay/modulator combinations. Enzyme activities of the phenobarbital and saline groups were statistically similar (P≥0.05) when assayed without modulator added, but each assay/modulator combination distinguished between these groups. The PCB-treated group was distinguished from the corn oil vehicle control group only for BROD activity, with or without the presence of modulator. Graphing of per cent modulation of BROD activity versus initial BROD activity provided the clearest distinction between all of the study groups. Identification of these selective in vitro modulators may improve detection and measurement of low level cytochrome P450 induction in avian species. Also, both the monooxygenase activities induced and the impacts of the modulators indicated differences between mammalian and avian cytochromes P450.

Journal: Comparative Biochemistry and Physiology Part C: Pharmacology, Toxicology and Endocrinology - COMP BIOCHEM PHYSIOL C PHARMACOL TOXICOL ENDOCRINOL , vol. 122, no. 2, pp. 273-281, 1999

DOI: 10.1016/S0742-8413(98)10119-6

Cumulative Annual

View Publication

( www.sciencedirect.com )

( linkinghub.elsevier.com )

Keywords (6)

Identification of in vitro cytochrome P450 modulators to detect induction by prototype inducers in the mallard duckling ( Anas platyrhynchos),10.1016/

References (21)

Liver microsomal alkoxyphenoxazone O-dealkylases of white leghorn chickens: response to mixed function oxidase inducers (Citations: 2)

Differential effects of phenobarbitone and 3-methylcholanthrene induction on the hepatic microsomal metabolism and cytochrome P-450-binding of phenoxazone and a homologous series of its n-alkyl ethers (alkoxyresorufins) (Citations: 74)

Ethoxy-, pentoxy- and benzyloxyphenoxazones and homologues: a series of substrates to distinguish between different induced cytochromes P-450 (Citations: 411)

Microsomal mixed function oxidases in an estuarine fish, Fundulus heteroclitus, and their induction as a result of environmental contamination (Citations: 24)

Comparative effects of mixed function oxidase inhibitors on adrenal and hepatic xenobiotic metabolism in the guinea pig (Citations: 2)


	The following links allow you to view full publications. These links are maintained by other sources not affiliated with Microsoft Academic Search.