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采用单克隆抗体抑制实验、酶水解法及血小板α－颗粒膜蛋白（ＧＭＰ１４０）检测等技术研究人血小板上中国蕲蛇毒（ＣＡＡＶ）受体的定位。结果发现：抗血小板糖蛋白Ⅰｂ（ＧＰⅠｂ）单克隆抗体ＳＺ－２、ＨＩＰ１显著抑制１２５Ｉ－ＣＡＡＶ和血小板特异性结合并呈浓度依赖性，最大抑制率分别为９４．７％±２．０％和８３．０％±２．９％；随糜蛋白酶水解血小板浓度和作用时间不断增加，血小板膜上的ＧＰⅠｂ不断被酶解去掉，１２５Ｉ－ＣＡＡＶ与血小板特异结合率不断下降，从８９．４％降至４．４％；抗ＧＰⅠｂ单抗ＨＩＰ１显著抑制ＣＡＡＶ活化的血小板表面ＧＭＰ１４０的表达，抑制程度与ＨＩＰ１浓度呈负相关（ｒ＝－０．９９２）。研究结果证明ＣＡＡＶ受体位于人血小板膜的ＧＰⅠｂ上。ＣＡＡＶ通过与人血小板上受体ＧＰⅠｂ结合而发挥其生物效应
The localization of the Chinese viper venom (CAAV) receptor on human platelets was investigated by monoclonal antibody inhibition assay, enzymatic hydrolysis method and detection of platelet α-granular membrane protein (GMP140). The results showed that anti-platelet glycoprotein Ⅰb (GPⅠb) monoclonal antibodies SZ-2 and HIP1 significantly inhibited platelet-specific binding of 125I-CAAV in a concentration-dependent manner with the maximum inhibitory rates of 94.7% ± 2.0% and 83.0% ± 2.9%. With the increase of chitinase hydrolyzing platelet concentration and action time, the GPⅠb of platelet membrane was continuously removed by enzymolysis. The specific binding rate of 125I-CAAV to platelet decreased continuously from 89.4% To 4.4%. Anti-GPIb monoclonal antibody HIP1 significantly inhibited the expression of GMP140 on CAAV-activated platelet surface. The inhibition was negatively correlated with the concentration of HIP1 (r = -0.992). The results demonstrate that the CAAV receptor is located on GPIb of human platelet membranes. CAAV exerts its biological effect by binding to GPIb, a receptor on human platelets