Abstract
The endothelium regulates vascular tone through the release of a number of soluble mediators, including NO, prostaglandin I2, and endothelium-derived hyperpolarizing factor. Epoxyeicosatrienoic acids are cytochrome P450 epoxygenase metabolites of arachidonic acid. They are synthesized by the vascular endothelium and open calcium-activated potassium channels, hyperpolarize the membrane, and relax vascular smooth muscle. Endothelium-dependent relaxations to acetylcholine, bradykinin, and shear stress that are not inhibited by cyclooxygenase and NO synthase inhibitors are mediated by the endothelium-derived hyperpolarizing factor. In arteries from experimental animals and humans, the non-NO, non-prostaglandin-mediated relaxations and endothelium-dependent hyperpolarizations are blocked by cytochrome P450 inhibitors, calcium-activated potassium channel blockers, and epoxyeicosatrienoic acid antagonists. Acetylcholine and bradykinin stimulate epoxyeicosatrienoic acid release from endothelial cells and arteries. These findings indicate that epoxyeicosatrienoic acids act as endothelium-derived hyperpolarizing factors and regulate arterial tone.
Original language | English (US) |
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Pages (from-to) | 590-596 |
Number of pages | 7 |
Journal | Hypertension |
Volume | 49 |
Issue number | 3 PART 2 SUPPL. |
DOIs | |
State | Published - Mar 2007 |
Keywords
- Arachidonic acid
- Cytochrome P450 system
- Endothelium
- Endothelium-derived hyperpolarizing factor
- Vascular relaxation
ASJC Scopus subject areas
- Internal Medicine