木瓜蛋白酶对凝血功能的抑制作用及机制的体外研究

目的: 观察木瓜蛋白酶体外对凝血功能的抑制作用,并探讨其可能机制。方法: 将不同剂量木瓜蛋白酶分别与贫血小板血浆(PPP)和富血小板血浆(PRP)作用,分为生理盐水组、10 U/L 组和 20 U/L 组,分别以血凝仪测定PPP和PRP的凝血酶原时间(PT)和活化部分凝血活酶时间(APTT),以血气分析仪和血凝仪分别测定PPP 的Ca²⁺浓度和凝血因子V、VII、VIII、IX、X和XI活性(FV:C、FVII:C、FVIII:C、FIX:C、FX:C和FXI:C);将新鲜全血与前述3种浓度木瓜蛋白酶作用,采用硅化管法测定全血凝血时间(CT)。同时测定0、20、40、60和 80 U/L 木瓜蛋白酶PPP的PT和APTT值。结果: 10 U/L和 20 U/L 木瓜蛋白酶组PPP和PRP的PT和APTT值、全血CT值分别显著高于生理盐水组和 10 U/L 木瓜酶组(P<0.01),FV:C和FVIII:C水平分别显著低于生理盐水组和 10 U/L 木瓜酶组(P<0.05);三组PPP与PRP之间PT和APTT值、各组间Ca²⁺浓度以及其余凝血因子活性差异均无显统计学意义(P>0.05)。PPP的PT和APTT值均与木瓜蛋白酶剂量呈显著正相关(r=0.995 和 0.991,P<0.01)。结论: 木瓜蛋白酶可通过抑制凝血因子V和VIII活性,从而对凝血功能有剂量依赖性的抑制作用,具有抗凝的功效。

In vitro inhibitory effect of papain on blood coagulation function and the related mechanism

AIM: To observe the in vitro effect of papain on blood coagulation function, and to explore the possible mechanism. METHODS: Human platelet poor plasma (PPP) and platelet rich plasma(PRP) were mixed with different dose of papain which were assigned into three groups (group 0 U/L, group 10 U/L and group 20 U/L). PPP and PRP were measured for prothrombin time(PT) and actvated partial thromboplastin time (APTT) with blood coagulation analyzer, the PPP was also measured for Ca²⁺ and activity of coagulable factor V, VII, VIII, IX, X and XI(FV:C、FVII:C、FVIII:C、FIX:C、FX:C and FXI:C) with blood-gas analyzer and blood coagulation analyzer, respectively. Fresh blood from volunteers was mixed with the three dose of papain, the clotting time(CT) was detected with silicified tube method. The PPP with 0, 20, 40,60 and 80 U/L of papain also was measured for PT and APTT.RESULTS: At group 10 U/L papain and group 20 U/L papain, PT and APTT of PPP and PRP as well as CT of whole blood was significantly higher, but FV:C and FVIII:C activity was remarkably lower than that at group physiological saline solution and group 10U/L papain, respectively. There was no statistical difference for PT and APTT between PPP and PRP at the three groups, for Ca²⁺ concentration and other four coagulable factors activity between the three groups one another. Either PT or APTT level at group 0,20, 40,60and 80U/L of papain showed positive correlation with papain dose. CONCLUSION: Papain has dose-dependent inhibitory effect on blood coagulation mainly through inhibition of coagulable facor V and VIII activity. Papain has the efficacy of anticoagulation