Gallocatechin Gallate Inhibits Platelet Aggregation by Arachidonic Acid Liberation and $TxA_2$ Synthase Activity

We have previously reported that green tea catechins (GTC) displayed anti-thrombotic activity, and that this might be due to anti-platelet rather than anti-coagulation effects. In the present study, we have studied the anti-platelet activity and mechanism of gallocatechin gallate (GCG), which is a component of GTC. GCG inhibited the collagen- and U46619-induced aggregation of rabbit platelets, with IC$\^$50/ values of 63.0 and 48.3 ${\mu}$M, respectively. GCG also inhibited collagen-induced serotonin release and TxB$_2$ formation in a similar manner of platelets aggregation. (omitted)