vasodilatative effects of cocoa was obtained by its capability to supress arginase enzyme activity which will lose in the competition with NO rndothelial synthase. this in turn will increase the production of NO. the other mechanism of cocoa on vasodilatation is associated with in creased epicatechin levels in plasma which will give a signal to release vasoactive components from endothelial cell, i.e., NO and prostacyclin. this process will also decrease ratio leukotriene-prostacyclin to cause vasodilatative effect.