An essential role of endothelium-derived nitric oxide in vasorelaxations induced by black tea polyphenols

Green tea has received much attention as protective agent against cardiovascular disease and cancer,the two primary targets of preventive medicine.Since our first demonstration in 1999 of the involvement of endothelium-derived nitric oxide in the acute vasodilator effect of green tea polyphenols,several new vascular protective effects of green tea catechins have been identified.Theaflavins are another class of polyphenol pigments found in black tea,however,little is known about their bioactivity in the vasc...