Cytochrome P450 isoforms in human fetal tissues related to phenobarbital-inducible forms in the mouse

doi:10.1016/0006-2952(93)90175-V

Biochemical Pharmacology

Volume 45, Issue 4, 24 February 1993, Pages 899-907

https://doi.org/10.1016/0006-2952(93)90175-V Get rights and content

Abstract

Four polyclonal antibodies raised against purified mouse liver cytochrome P450s representing Cypla, Cyp2a, Cyp2b and Cyp2c subfamilies were used to detect their related forms in human adult and fetal tissues. In immunoblot analysis, anti-Cyp2c antibody detected two to three proteins in adult livers and one to three proteins in 70% of the 18 fetal livers studied. Anti-Cyp2a-5 antibody recognized a 50-kDa protein in 50% of the fetal adrenals. Anti-Cypla-2 antibody reacted with a single protein (55 kDa) in adult liver. The anti-Cyp2b-10 antibody did not detect proteins in any of the tissues. No proteins were detected in fetal kidneys. There was no coumarin 7-hydroxylase activity (COH) in fetal liver or adrenals. The 7-ethoxycoumarin O-deethylase (ECOD) activities were slightly higher in fetal adrenals (mean 6.1 pmol/mg protein/min) vs livers. The fetal adrenal ECOD activity was not inhibited by the anti-Cyp2a-5 antibody. Aryl hydrocarbon hydroxylase (AHH) activities in fetal livers were about 5% of those in adult livers. AHH activity in fetal liver was not inhibited by the anti-Cyp2c antibody. Testosterone 6β-hydroxylase activity was much lower in fetal liver than in adult liver (about 20 and 1700 pmol/mg protein/min, respectively). No immunoinhibition occurred in fetal adrenal progesterone hydroxylation, hepatic benzphetamine N-demethylation and hepatic ethylmorphine N-demethylation. These data suggest that members of the P450 subfamilies 1A, 2A and 2B are expressed at a very low level in fetal liver, and that fetal liver may contain members of the 2C subfamily.

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Cytochrome P450 isoforms in human fetal tissues related to phenobarbital-inducible forms in the mouse

Abstract

Life Sci

Pharmacol Ther

Arch Biochem Biophys

Arch Biochem Biophys

Biochem Pharmacol

Arch Biochem Biophys

Biochem Pharmacol

J Biol Chem

Anal Biochem

J Biol Chem

Biochem Pharmacol

Biochem Pharmacol

Chromatography

J Steroid Biochem Mol Biol

Biochem Pharmacol

J Steroid Biochem Mol Biol

Biochem Biophys Res Commun

Biochem Pharmacol

Biochem Biophys Res Commun

Biochim Biophys Acta

J Biol Chem

Arch Biochem Biophys

Biochem Pharmacol

The molecular biology of cytochrome P450s

Pharmacol Rev

The P450 superfamily: update on new sequences, gene mapping, and recommended nomenclature

DNA Cell Biol

Immunoquantification of epoxide hydrolase and cytochrome P-450 isozymes in fetal and adult human liver microsomes

Eur J Biochem

Purification and characterization of a liver microsomal cytochrome P-450 isozyme with a high affinity and metabolic capacity for coumarin from pyrazole-treated D2 mice

Eur J Biochem