Faculty Collaboration Database

Adrenic acid metabolites as endogenous endothelium-derived and zona glomerulosa-derived hyperpolarizing factors. Hypertension 2010 Feb;55(2):547-54

Date

12/30/2009

Pubmed ID

20038752

Pubmed Central ID

PMC2819927

DOI

10.1161/HYPERTENSIONAHA.109.144147

Scopus ID

2-s2.0-74949098446 (requires institutional sign-in at Scopus site)   32 Citations

Abstract

Adrenic acid (docosatetraenoic acid), an abundant fatty acid in the adrenal gland, is identical to arachidonic acid except for 2 additional carbons on the carboxyl end. Adrenic acid is metabolized by cyclooxygenases, cytochrome P450s, and lipoxygenases; however, little is known regarding the role of adrenic acid and its metabolites in vascular tone. Because of its abundance in the adrenal gland, we investigated the role of adrenic acid in vascular tone of bovine adrenal cortical arteries and its metabolism by bovine adrenal zona glomerulosa cells. In adrenal cortical arteries, adrenic acid caused concentration-dependent relaxations, which were inhibited by the epoxyeicosatrienoic acid antagonist 14,15-epoxyeicosa-5(Z)-enoic acid and the cytochrome P450 inhibitor SKF-525A. The large-conductance calcium-activated potassium channel blocker iberiotoxin or removal of the endothelium abolished these relaxations. Reverse-phase high-pressure liquid chromatography and liquid chromatography/mass spectrometry isolated and identified numerous adrenic acid metabolites from zona glomerulosa cells, including dihomo-epoxyeicosatrienoic acids and dihomo-prostaglandins. In denuded adrenal cortical arteries, adrenic acid caused concentration-dependent relaxations in the presence of zona glomerulosa cells but not in their absence. These relaxations were inhibited by SKF-525A, 14,15-epoxyeicosa-5(Z)-enoic acid, and iberiotoxin. Dihomo-16,17-epoxyeicosatrienoic acid caused concentration-dependent relaxations of adrenal cortical arteries, which were inhibited by 14,15-epoxyeicosa-5(Z)-enoic acid and high potassium. Our results suggest that adrenic acid relaxations of bovine adrenal cortical arteries are mediated by endothelial and zona glomerulosa cell cytochrome P450 metabolites. Thus, adrenic acid metabolites could function as endogenous endothelium-derived and zona glomerulosa-derived hyperpolarizing factors in the adrenal cortex and contribute to the regulation of adrenal blood flow.

Author List

Kopf PG, Zhang DX, Gauthier KM, Nithipatikom K, Yi XY, Falck JR, Campbell WB

Authors

William B. Campbell PhD Professor in the Pharmacology and Toxicology department at Medical College of Wisconsin
David X. Zhang MD, PhD Associate Professor in the Medicine department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adrenal Glands
Analysis of Variance
Animals
Biological Factors
Cattle
Cells, Cultured
Chromatography, High Pressure Liquid
Cytochrome P-450 Enzyme System
Endothelium, Vascular
Erucic Acids
Fatty Acids, Unsaturated
Potassium Channels, Calcium-Activated
Proadifen
Probability
Vascular Resistance
Vasodilation
Zona Glomerulosa