The Expression of Genes CYP1A1, CYP1B1, and CYP2J3 in Distinct Regions of the Heart and Its Possible Contribution to the Development of Hypertension.

Background: It is believed that alterations in the functioning of the cytochrome P450 (CYP), which participates in metabolic transformations of endogenous polyunsaturated fatty acids (PUFAs) (with the formation of cardioprotective or cardiotoxic products), affects the development of age-related cardiovascular diseases and reduces the effectiveness of some cardioselective drugs. For example, CYP2J2 activation or CYP1B1 inhibition protects against the cardiovascular toxicity of anticancer drugs. It is currently unclear whether CYPs capable of metabolizing arachidonic acid and ω-3 PUFAs to vasodilatory and vasoconstrictive derivatives are expressed in all heart regions.

Methods: The work was performed on senescence-accelerated OXYS rats featuring elevated blood pressure, OXYSb rats (an OXYS substrain with normal blood pressure), and Wistar rats as a "healthy" control. The mRNA level was determined in the right and left ventricles, the right and left atria, and the aorta of 1-, 3-, and 12-month-old rats.

Results: We showed that all heart regions express CYPs capable of metabolizing arachidonic acid and ω-3 PUFAs and revealed significant differences between heart regions both in the mRNA level of genes CYP1B1, CYP2J3, and CYP1A1 and in the time course of expression changes with age.

Conclusions: We noticed that expression levels of these CYPs in the heart regions and aorta differ between hypertensive OXYS rats, normotensive OXYSb rats, and healthy Wistar rats but could not detect any clear-cut patterns associated with the hypertensive status of OXYS rats.