Expression and Inducibility of Cytochrome P450 3A9 (CYP3A9)and Other Members of the CYP3A Subfamily in Rat Liver

doi:10.1006/abbi.1996.9752

Archives of Biochemistry and Biophysics

Volume 337, Issue 1, 1 January 1997, Pages 62-68

https://doi.org/10.1006/abbi.1996.9752 Get rights and content

Abstract

Quantitative reverse-transcriptase polymerase chain reaction was used to determine the content of mRNA derived from four CYP3A genes (CYP3A2, CYP3A9, CYP3A18,andCYP3A23) in rat liver. CYP3A2 and CYP3A9 gene expression was age- and sex-dependent, whereas CYP3A18 and CYP3A23 mRNA were observed before and after puberty at fairly constant levels that were about 20% higher in males than in females. CYP3A9 mRNA was detected only in adult rats, with a nearly twofold higher expression in females. CYP3A9 induction was different from other CYP3A isoenzymes, since phenobarbital was a more effective inducer than dexamethasone and clotrimazole. The results presented for CYP3A23 are those anticipated for CYP3A1, which may be an allelic variant of CYP3A23 not detected in these experiments. These data show that rat CYP3A genes are variably expressed depending on age, sex, or inducer type.

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Citation Excerpt :
Potential involvement of progesterone in altered drug metabolism during human pregnancy is currently under investigation. On the other hand, CYP3A9 expression is not governed by PXR ([33] and Fig. 2). Interestingly, consistent with our data indicating increased CYP3A9 expression upon EB treatment, CYP3A9 expression has shown to be female-specific and enhanced by ethinylestradiol in rats [31,34].
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^☆: The EMBL/GenBank accession number for the sequence of olf3 (CYP3A9) is U60085.

²: To whom correspondence should be addressed at the Institute for Physiological Chemistry, MA2/136, Ruhr University Bochum, D-44780 Bochum, FRG. Fax: +49-234-7094-314. E-mail: [email protected].

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Regular ArticleExpression and Inducibility of Cytochrome P450 3A9 (CYP3A9)and Other Members of the CYP3A Subfamily in Rat Liver☆

Abstract

Regular Article
Expression and Inducibility of Cytochrome P450 3A9 (CYP3A9)and Other Members of the CYP3A Subfamily in Rat Liver☆