14,15-Epoxyeicosa-5(Z)-enoic acid: a selective epoxyeicosatrienoic acid antagonist that inhibits endothelium-dependent hyperpolarization and relaxation in coronary arteries. Circ Res 2002 May 17;90(9):1028-36
Date
05/23/2002Pubmed ID
12016270DOI
10.1161/01.res.0000018162.87285.f8Scopus ID
2-s2.0-0037123936 (requires institutional sign-in at Scopus site) 177 CitationsAbstract
Endothelium-dependent hyperpolarization and relaxation of vascular smooth muscle are mediated by endothelium-derived hyperpolarizing factors (EDHFs). EDHF candidates include cytochrome P-450 metabolites of arachidonic acid, K(+), hydrogen peroxide, or electrical coupling through gap junctions. In bovine coronary arteries, epoxyeicosatrienoic acids (EETs) appear to function as EDHFs. A 14,15-EET analogue, 14,15-epoxyeicosa-5(Z)-enoic acid (14,15-EEZE) was synthesized and identified as an EET-specific antagonist. In bovine coronary arterial rings preconstricted with U46619, 14,15-EET, 11,12-EET, 8,9-EET, and 5,6-EET induced concentration-related relaxations. Preincubation of the arterial rings with 14,15-EEZE (10 micromol/L) inhibited the relaxations to 14,15-EET, 11,12-EET, 8,9-EET, and 5,6-EET but was most effective in inhibiting 14,15-EET-induced relaxations. 14,15-EEZE also inhibited indomethacin-resistant relaxations to methacholine and arachidonic acid and indomethacin-resistant and L-nitroarginine-resistant relaxations to bradykinin. It did not alter relaxation responses to sodium nitroprusside, iloprost, or the K(+) channel activators (NS1619 and bimakalim). Additionally, in small bovine coronary arteries pretreated with indomethacin and L-nitroarginine and preconstricted with U46619, 14,15-EEZE (3 micromol/L) inhibited bradykinin (10 nmol/L)-induced smooth muscle hyperpolarizations and relaxations. In rat renal microsomes, 14,15-EEZE (10 micromol/L) did not decrease EET synthesis and did not alter 20-hydroxyeicosatetraenoic acid synthesis. This analogue acts as an EET antagonist by inhibiting the following: (1) EET-induced relaxations, (2) the EDHF component of methacholine-induced, bradykinin-induced, and arachidonic acid-induced relaxations, and (3) the smooth muscle hyperpolarization response to bradykinin. Thus, a distinct molecular structure is required for EET activity, and alteration of this structure modifies agonist and antagonist activity. These findings support a role of EETs as EDHFs.
Author List
Gauthier KM, Deeter C, Krishna UM, Reddy YK, Bondlela M, Falck JR, Campbell WBAuthor
William B. Campbell PhD Professor in the Pharmacology and Toxicology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid8,11,14-Eicosatrienoic Acid
Animals
Arachidonic Acid
Benzimidazoles
Benzopyrans
Bradykinin
Cattle
Coronary Vessels
Dihydropyridines
Dose-Response Relationship, Drug
Endothelium, Vascular
Iloprost
In Vitro Techniques
Kidney Cortex
Male
Microsomes
Muscle, Smooth, Vascular
Nitroprusside
Rats
Rats, Sprague-Dawley
Structure-Activity Relationship
Vasoconstriction
Vasoconstrictor Agents
Vasodilation
