重楼皂苷H诱导血小板聚集效应及其机制的研究

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

目的确定从中药重楼中分离的重楼皂苷H(PARG)对血小板聚集的直接诱导效应,并对其诱导血小板聚集的机制进行探索。方法雄性Wistar大鼠心脏取血,离心分离获得富血小板血浆,样品中加入不同浓度重楼皂苷H,比浊法检测血小板聚集情况。分别用不同浓度的血小板膜糖蛋白Ⅱb/Ⅲa受体拮抗剂(RGDS)、ADP抑制剂腺苷三磷酸双磷酸酶(Apyrase)、PKC抑制剂Ro31-8820和TXA2受体阻断剂SQ29548孵育血小板3min,加入重楼皂苷H诱导血小板聚集,观察各抑制剂对血小板聚集的影响。结果 PARG能直接诱导大鼠血小板聚集,呈现剂量效应,高浓度PARG(30μmol/L)可诱导血小板发生不可逆聚集。1mmol/LRGDS和0.5μmol/LSQ29548几乎完全抑制PARG诱导的血小板聚集;Apyrase(0.05～1U/ml)和Ro31-8220(20～50μmol/L)均呈剂量依赖效应抑制PARG诱导的血小板聚集。结论 PARG诱导血小板聚集依赖于血小板激活后ADP的释放和TXA2的生成。

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.