尖吻蝮蛇毒活性肽K组分对血小板聚集和超微结构的影响

The effects of a small peptide from Agkistrodon acutus venom on the ultrastructure of platelets

目的应用电镜研究尖吻蝮蛇毒活性肽(K组分)对血小板聚集和超微结构的影响,以探讨其抗血小板聚集的机制。方法取2周内未服任何药物健康志愿者静脉血,观察K组分对二磷酸腺苷(ADP)和胶原(collagen)诱导的血小板聚集作用的影响。将已调好的PRP分为5组,A组为空白对照组,B、D组为加入等体积的生理盐水组,C、E组为加K组分组。B、C组分别加血小板聚集诱导剂ADP,D、E组分别加血小板聚集诱导剂胶原,各组分别制成超薄切片样品进行电镜观察、摄片,测出其聚集抑制率。结果K组分能抑制由ADP和胶原诱导的血小板聚集,剂量与抑制率成量效关系,IC50经直线回归分别为0.067和0.088μmol/L。ADP和胶原组血小板形态不规则,突起明显增多。K组分组血小板形态基本规则,膜表面清晰光滑,颗粒较ADP与胶原组明显增加,胞浆空泡化现象减轻。结论K组分明显抑制ADP和胶原诱导的血小板聚集反应及其超微结构的改变。

Objective To investigate the effects of a small peptide from Agkistrodon acutus venom（Fraction K） on ultrastructure of platelets by electron microscop. Methods The effects of Fraction K on ADP and collagen induced platelet aggregation were detected by tubidmetry; the ultrastructure changes of platelet were analyzed by e- lectro microscope. Results Fraction K dose-dependently inhibited the platelet aggregation induced by ADP and collagen. The IC50was 0. 067 and 0. 088 μmol/L respctively. In the ADP and collagen group the platelet morphology is anomalism and many pseudopods protruded. In the Fraction K group the platelet morphology and ultrastructure approach blank group. The platelet is very smooth. Fraction K can inhibit producing pseudopods process and increase in the number of the gran- ules associated with enhanced intensities of their electron densities. Conclusion Ifs showed that Fraction K can signcantly inhibit platelet aggregation and ultra- structural changes.