Study on the effect and mechanism of Chonglouoside H on platelet aggregation

Objective To comfirm the effects of Chonglouoside H(PARG),purified from Paris polyphylla Sm.var.yunnanensis (TSSPs),on platelet aggregation,and explore the underlying mechanisms.Methods Blood samples were obtained from heart of Wistar rats to acquire platelet-rich plasma by centrifugation,followed by addition of different concentrations of PARG,and turbidimetric method was applied to determine the aggregation of platelets.Moreover,platelet-rich plasma was incubated for 3min with RGDS,Apyrase,Ro31-8820or SQ29548,which were the inhibitors of glycoprotein IIb/IIIa,GP IIb/IIIa receptors,ADP,PKC and a blocker of TXA2receptor, respectively.Subsequently,the PARG was added to observe the effects of platelet aggregation.Results PARG induced the aggregation of platelets in a dose-dependent manner,and a high dose of PARG (30μmol/L)might induce a nonreversible aggregation.RGDS and SQ29548,in a dose of 1mmol/L and 0.5μmol/L respectively,almost totally inhibited PARG-induced aggregation.Apyrase(0.05～1U/ ml)and Ro31-8220(20～50μmol/L)inhibited PARG-induced aggregation in a dose-dependent manner.Conclusion PARG may induce the aggregation of platelets,depending on the production of ADP and TXA2after activation of platelets.