A study of mechanisms involved in vasodilatation induced by resveratrol in isolated porcine coronary artery.
The present study was designed to investigate the acute relaxing effect of phytoestrogen resveratrol on isolated porcine coronary arteries and to determine the mechanisms underlying its vasodilatation. Rings of porcine coronary arteries were suspended in organ baths containing Krebs-Henseleit solution, and then isometric tension was measured. Resveratrol concentration-dependently relaxed arterial rings precontracted with 30 mM KCl. The IC(50) value of resveratrol was 38.67+/-3.21 microM. Incubation with N(omega)-L-nitro-arginine (L-NNA), endothelium removal or the presence of a potent inhibitor of protein tyrosine phosphatase sodium orthovanadate partly decreased the relaxation induced by resveratrol. However, the relaxation induced by resveratrol was unaffected by the estrogen receptor antagonist tamoxifen, the inhibitor of prostanoid synthesis indomethacin, the antagonist of beta-adrenoceptors propranolol or the protein synthesis inhibitor, cycloheximide. In addition, resveratrol significantly decreased the contractile responses of 5-HT, KCl and CaCl(2), and shifted their cumulative concentration-response curves to the right. These results suggest that the mechanisms of vasorelaxation induced by resveratrol are heterogeneous, two mechanisms participating partially in the relaxation of porcine coronary artery were detected in the study, one being the nitric oxide released from the endothelium, the other causing inhibition of Ca(2+) influx, but estrogen receptors were not involved in resveratrol-induced relaxation.
Li
Hong-Fang
HF
Department of Physiology, College of Basic Medicine, Lanzhou University, Lanzhou, People's Republic of China. lihf@lzu.edu.cn
Tian
Zhi-Feng
ZF
Qiu
Xiao-Qing
XQ
Wu
Jin-Xia
JX
Zhang
Peng
P
Jia
Zhong-Jian
ZJ
D000818:Animals; D002118:Calcium / Q000378:metabolism; D003326:Coronary Circulation / Q000187:drug effects*; D003331:Coronary Vessels / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D066298:In Vitro Techniques; D008297:Male; D009569:Nitric Oxide / Q000378:metabolism; D019335:Nitroarginine / Q000494:pharmacology; D011189:Potassium Chloride / Q000494:pharmacology; D011453:Prostaglandins / Q000378:metabolism; D011943:Receptors, Adrenergic, beta / Q000378:metabolism; D000077185:Resveratrol; D012701:Serotonin / Q000494:pharmacology; D018490:Serotonin Agents / Q000494:pharmacology; D013267:Stilbenes / Q000494:pharmacology*; D013552:Swine; D014664:Vasodilation / Q000187:drug effects*; D014665:Vasodilator Agents / Q000494:pharmacology*
D004791:Enzyme Inhibitors; D011453:Prostaglandins; D011943:Receptors, Adrenergic, beta; D018490:Serotonin Agents; D013267:Stilbenes; D014665:Vasodilator Agents; D019335:Nitroarginine; D009569:Nitric Oxide; D012701:Serotonin; D011189:Potassium Chloride; D000077185:Resveratrol; D002118:Calcium