Tanoue K, Jung S M, Yamamoto N, Yamazaki H
Thromb Haemost. 1984 Feb 28;51(1):79-83.
Pretreatment of platelets with chymotrypsin dose-dependently decreased glycoprotein (GP)-Ib amounts as measured by SDS-PAGE, ristocetin-induced agglutination and platelet electrophoretic mobility (EPM). Decrease in platelet EPM in response to 0.75 mg/ml ristocetin alone were 7.0 +/- 2.3 and 6.8 +/- 4.3% (M +/- S.E., n = 6) for control and chymotrypsin-treated platelets, respectively (p greater than 0.2). Von Willebrand factor (vWF) alone had no effect on platelet EPM. However, in the presence of 0.75 mg/ml ristocetin, added vWF (2.9 micrograms/ml) caused a further 6.3 +/- 3.8% decrease in control platelet EPM, but caused no significant decrease in the enzyme-treated platelets (p less than 0.05). In the presence of 0.3 mg/ml ristocetin, added vWF (2.9-14.5 micrograms/ml) caused a small but significant decrease in control platelet EPM, but caused no significant decrease in the enzyme-treated platelets. These findings suggested that the GP-Ib carrying negative charge decreased by binding of vWF might facilitate a mutual approach of the GP-Ib molecules and bridge formation by vWF between different platelets.
用胰凝乳蛋白酶对血小板进行预处理后，通过十二烷基硫酸钠 - 聚丙烯酰胺凝胶电泳（SDS - PAGE）、瑞斯托霉素诱导的凝集反应和血小板电泳迁移率（EPM）测定，糖蛋白（GP）- Ib的量呈剂量依赖性减少。单独使用0.75mg/ml瑞斯托霉素时，对照血小板和经胰凝乳蛋白酶处理的血小板的EPM降低分别为7.0±2.3%和6.8±4.3%（均值±标准误，n = 6）（p＞0.2）。单独的血管性血友病因子（vWF）对血小板EPM没有影响。然而，在存在0.75mg/ml瑞斯托霉素的情况下，添加的vWF（2.9μg/ml）使对照血小板EPM进一步降低6.3±3.8%，但在酶处理的血小板中未引起显著降低（p＜0.05）。在存在0.3mg/ml瑞斯托霉素的情况下，添加的vWF（2.9 - 14.5μg/ml）使对照血小板EPM有小幅但显著的降低，但在酶处理的血小板中未引起显著降低。这些发现表明，通过vWF结合而减少的带负电荷的GP - Ib可能促进GP - Ib分子相互靠近，并促进vWF在不同血小板之间形成桥连。
