中华眼镜蛇毒组份M抑制血小板聚集作用机制初探

探讨中华眼镜蛇毒组份Ｍ抑制血小板聚集作用机制；方法：运用卵磷脂法、剩余可凝纤维蛋白原法、纤维蛋白平板法等分别测定了中华眼镜蛇毒组份Ｍ中磷脂酶Ａ_２（ＰＬＡ_２），纤维蛋白原溶解酶及纤维蛋白溶解等与血小板聚集相关的酶活性，并运用十二烷基磺酸钠一聚丙烯酰胺凝胶垂直板电泳（ＳＤＳ－ＰＡＧＥ）分析了组份Ｍ对血小板内细胞骨架蛋白的影响；结果：组份 Ｍ不含 ＰＬＡ_２活性，无纤维蛋白（原）溶解酶活性，亦无ＡＤＰ酶和 ５’－核苷酸酶活性，不影响正常人血浆乳酸脱氢酶的含量，但对ＡＤＰ诱导的血小板细胞内肌动蛋白微丝聚合物的形成有明显抑制作用；结论：中华眼镜蛇毒组份Ｍ对血小板聚集所依赖的血小板内细胞骨架系统的功能有抑制作用。

Preliminary Study on the Mechanism of Inhibitory Effect of Fraction M from Naja naja atra Snake Venom on Platelet Aggregation

Objective: To explore the mechanism of platelet aggregation-inhibitory effect induced by frac- tion M from the venom of Naja naja atra snake. Method: By using the test of lecithin hydrolysis, the test of residual clotted fibrinogen and that of fibrin plate, the activity of phospholipase A_2 (PLA_2), the activity of fibrinogenolytic enzyme and the fibrinolysis, Which are related to platelet aggrega- tion, were detected. Furthermore, SDS-PAGE electrophoresis technique was used tO investigate the effect of fraction M on platelet cytoskeleton proteins. Results: Fraction M was free of PLA_2 activi- ty, fibrino(geno) lytic activity, ADPase, or 5 '-nucleotidase, and it exerted no effect on the content of plasma lactic dehydrogenase from normal human. However, an obvious inhibitory effect of fraction M on the formation of actin filament polymer in platelet induced by ADP was observed. Conclu- sion:Fraction M could inhibit the function of platelet cytoskeleton on which the aggregation of platelet depends.