Mechanism related to docosahexaenoic acid induced large conductance calcium-activated potassium channel currents increase in coronary smooth muscle cells / 中华心血管病杂志
Chinese Journal of Cardiology
;
(12): 348-352, 2011.
Article
in Chinese
| WPRIM
| ID: wpr-272247
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the mechanism of enhanced large conductance calcium-activated potassium channel currents (BK) in coronary smooth muscle cells (SMCs) by docosahexaenoic acid (DHA).</p><p><b>METHODS</b>Coronary SMCs were isolated by enzyme digestion. Potassium channels in coronary SMCs were identified by applications of different potassium blockers. Effects of DHA and its metabolite 16, 17-epoxydocosapentaenoic acid (16, 17-EDP) on BK channels in the absence and presence of cytochrome P450 epoxygenase inhibitor SKF525A were studied by patch clamp in whole-cell configuration.</p><p><b>RESULTS</b>BK channels were widely distributed in SMCs, and BK currents in normal SMCs accounted for (64.2 ± 2.7)% of total potassium currents (n = 20). DHA could activate BK channels, and its 50% effective concentration (EC(50)) was (0.23 ± 0.03) µmol/L, however, the effect of DHA on BK channels was abolished after SMCs were incubated with cytochrome P450 epoxygenase inhibitor SKF525A. 16, 17-EDP, a metabolite of DHA, could reproduce the effects of DHA on BK channels, and its EC(50) was (19.7 ± 2.8) nmol/L.</p><p><b>CONCLUSION</b>DHA and metabolites can activate BK channels and dilate coronary arteries through activating cytochrome P450 epoxygenase pathway.</p>
Full text:
Available
Index:
WPRIM (Western Pacific)
Main subject:
Pharmacology
/
Proadifen
/
Docosahexaenoic Acids
/
Rats, Sprague-Dawley
/
Coronary Vessels
/
Cell Biology
/
Myocytes, Smooth Muscle
/
Large-Conductance Calcium-Activated Potassium Channels
/
Fatty Acids, Unsaturated
/
Cytochrome P-450 Enzyme Inhibitors
Limits:
Animals
Language:
Chinese
Journal:
Chinese Journal of Cardiology
Year:
2011
Type:
Article
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