兔血小板被A23187、凝血酶、ADP激活时其超微结构和颗粒数的变化

EFFECTS OF CALCIUMIONOPHORE A23187,THROMBIN AND ADP ON THE ULTRASTRUCTURE AND SECRETORY GRANULE NUMBER OF RABBIT BLOOD PLATELETS

研究钙离子导体Ａ２３１８７（１μｍｏｌ／Ｌ）、凝血酶（２ｕ／ｍｌ）、腺苷二磷酸（ＡＤＰ，２００μｍｏｌ／Ｌ）激活血小板的超微结构和颗粒数的变化。采用电子显微术和颗粒数密度（Ｎｖ）计量法。结果：激活的血小板有变形，包括伪足生成，颗粒移向中央区，微管解聚，分泌颗粒的胞吐现象及分泌颗粒减少等一系列反应，３种激动剂所引起的形态变化并无明显差异。小剂量Ａ２３１８７引起αＧ和ｄＧ的数密度分别下降５２．８８％和３６．０２％，两者差异显著（Ｐ＜０．０１）。用量大的ＡＤＰ对两种颗粒促释放的影响则无差异。结论：激动剂作用较弱时αＧ较ｄＧ更易释放。

PURPOSE To study the alteration of ultrastructure and granule number of platelets stimulated by calcium ionophore A23187 1μmol/L,thrombin 2 u/ml and ADP 200μmol/L.METHODS The electron microscopy and morphometry of granule numerical density (Nv) was used in the study. RESULTS It was observed that the shape changes including pseudopod formation, microtubule disassembly, granule-exocitosis and decrease in secretory granule number could be induced by these 3 agonists and without any marked difference among their inducing changes. The morphometry study showed that a smaller dosage of A23187 resulted in a decrease of α granules by 52.88% and of dense(d) granules by 36.02 %,the difference being statistical significant.The larger dosage of ADP decreased the Nv ofα and d granules in the same extent.CONCLUSIONS The finding indicate that the response ofαgranules occurs more readily than granules to weaker activation.