We have discovered that bcrberine (BR) is an anti-platelet drug.It was demonstrated that BR inhibited ADP-, arachidonate-, collagen-and calcium ionophorc A231S7-xnduced platelet aggregation and ATP release in different degrees.Especially BR strongly inhibited collagen-induced platelet aggregation and ATP release reaction(IC50 values were 0.12 and 0.08 mmol/L,respectively).The antiplatekt mechanism of BR may be inhibition of arachidonate metabolism,, and suppression of the rise of intracdlular Ca2' and/or cA...