Volume 56 (2006) Issue: 2006 No#2-3

Endothelium – dependent relaxation of internal mammary artery produced by resveratrol

Author(s): Novaković Aleksandra, Gojkovi} Bukarica Ljiljana, Perić M, Nezić D, Đukanovic B, Lešić A, Bumbasirevic M, Markovic-Lipkovski Jasmina

Keywords:mammary artery, K+ channel, NO, resveratrol, vasorelaxation

Resveratrol, a polyphenol present in wine, has been thought to be responsible for cardiovascular benefits associated with moderate wine consuption. It is also present in the plant Polygonum Cuspidatum. The mechanism of cardiovascular benefits probably includes vasorelaxation, antioxidant and anti-platelet effects of resveratrol. The mechanisms by which resveratrol causes vasodilatation are uncertain. The aim of this study was to investigate the mechanism(s) of resveratrolinduced vasorelaxation in human internal mammary artery (HIMA) with endothelium. HIMA rings were precontracted by phenylephrine. Resveratrol induced relaxation of the HIMA rings with endothelium. LNAME, an inhibitor of NO synthase, and methylene blue, an inhibitor of guanylate cyclase, abolished relaxation of HIMA, induced by resveratrol. Highly selective blocker of ATP-sensitive K+ channels, glibenclamide as well as a nonselective blocker of big Ca-sensitive K+ channels, charybdotoxin did not block resveratrol-induced relaxation of HIMA. 4-Aminopyridine and margatoxin, blockers of voltage-gated K+ (KV) channels, abolished endothelium-dependent relaxation of HIMA, induced by resveratrol. In conclusion, we have shown that resveratrol induces relaxation of HIMA with endothelium. It seems that NO and smooth muscle KV channels are included in this relaxation.