Arai M, Yamamoto N, Moroi M, Akamatsu N, Fukutake K, Tanoue K
Department of Clinical Pathology, Tokyo Medical College, Japan.
Br J Haematol. 1995 Jan;89(1):124-30. doi: 10.1111/j.1365-2141.1995.tb08900.x.
Platelet glycoprotein VI (GPVI), a 62kD membrane protein, has been identified as one of the platelet receptors for collagen, since GPVI-deficient platelets exhibit abnormal responses to collagen and an abnormal bleeding tendency. We report a female patient with a mild bleeding history whose platelets expressed 10% GPVI of normal platelets. Shape change, aggregation and ATP release of the patient's platelets were completely absent in response to 1-5 micrograms/ml collagen but present normally in response to ADP and Ca2+ ionophore A23187. Adhesion of the patient's platelets to coated collagen was mildly affected (40-60% of normal platelets) in spite of only 10% expression of GPVI. Flow cytometrical studies revealed that the patient's platelets expressed normal amounts of the GPIa/IIa complex. These results suggest that platelet GPVI is less involved in adhesion to collagen than shape change and aggregation induced by collagen.
血小板糖蛋白VI（GPVI）是一种62kD的膜蛋白，已被确定为血小板胶原蛋白受体之一，因为缺乏GPVI的血小板对胶原蛋白表现出异常反应和异常出血倾向。我们报告了一名有轻度出血史的女性患者，其血小板表达的GPVI为正常血小板的10%。该患者的血小板对1-5微克/毫升胶原蛋白无形状改变、聚集和ATP释放反应，但对ADP和钙离子载体A23187反应正常。尽管该患者血小板的GPVI仅表达10%，但其血小板与包被胶原蛋白的黏附受到轻度影响（为正常血小板的40-60%）。流式细胞术研究显示，该患者的血小板表达正常量的GPIa/IIa复合物。这些结果表明，血小板GPVI在与胶原蛋白黏附方面的作用小于胶原蛋白诱导的形状改变和聚集。
