Abstract
The cytochrome P450 (P450) enzymes CYP2C8, CYP2C9, and CYP2J2 metabolize arachidonic acid to epoxyeicosatrienoic acids, which are known to be vital in regulation of vascular tone and cardiovascular homeostasis. Because there is limited information regarding the relative expression of these P450 enzymes in cardiovascular tissues, this study examined the expression of CYP2C8, CYP2C9, and CYP2J2 mRNA and protein in human heart, aorta, and coronary artery samples by real-time polymerase chain reaction, immunoblotting, and immunohistochemistry. CYP2J2 and CYP2C9 mRNA levels were highly variable in human hearts, whereas CYP2C8 mRNA was present in lower abundance. CYP2J2 mRNA was approximately 103 times higher than CYP2C9 or CYP2C8 in human heart. However, CYP2C9 mRNA was more abundant than CYP2J2 or CYP2C8 in one ischemic heart. In human aorta, mean CYP2C9 mRNA levels were ∼50 times higher than that of CYP2J2 and 5-fold higher than that of CYP2C8. In human coronary artery, mean values for CYP2C9 mRNA were ∼2-fold higher than that of CYP2J2 mRNA and 6-fold higher than that of CYP2C8 mRNA. Immunoblotting results show relatively high levels of CYP2J2 and CYP2C8 protein in human hearts, which was confirmed by immunohistochemistry. CYP2C9 protein was also detected at high levels in one ischemic heart by immunoblotting. CYP2C9 was present at higher levels than CYPJ2 in aorta and coronary artery, whereas CYP2C8 protein was below the limits of detection. The expression of CYP2J2 and CYP2C8 in human heart, and CYPC9 and CYP2J2 in aorta and coronary artery is consistent with a physiological role for these enzymes in these tissues.
Footnotes
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This research was supported in part by the Intramural Research Program of the National Institutes of Health, National Institute of Environmental Health Sciences. This work was previously presented at the Experimental Biology 2006-ASPET Program (DeLozier et al., 2006).
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Article, publication date, and citation information can be found at http://dmd.aspetjournals.org.
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doi:10.1124/dmd.106.012823.
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ABBREVIATIONS: ROS, reactive oxygen species; P450, cytochrome P450; EET, epoxyeicosatrienoic acid; EDHF, endothelium-derived hyperpolarizing factor; PCR, polymerase chain reaction.
- Received September 12, 2006.
- Accepted January 5, 2007.
- The American Society for Pharmacology and Experimental Therapeutics
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