Lominadze David, Dean William L
Department of Physiology and Biophysics, School of Medicine, University of Louisville, Louisville, KY 40292, USA.
FEBS Lett. 2002 Apr 24;517(1-3):41-4. doi: 10.1016/s0014-5793(02)02575-9.
Increased fibrinogen concentration and erythrocyte aggregation are significant risk factors during various cardiovascular diseases and cerebrovascular disorders. Currently, fibrinogen-induced erythrocyte aggregation is thought to be caused by a non-specific binding mechanism. However, the published data on changes in erythrocyte aggregation during hypertension point to the possible existence of other mechanism(s). Therefore, we tested the hypothesis that specific binding of fibrinogen is involved in erythrocyte aggregation. It was found that Oregon Green 488-labeled human fibrinogen specifically binds rat erythrocyte membranes with a Kd of 1.3 microM. Further experiments showed that the peptide Arg-Gly-Asp-Ser blocked both fibrinogen-induced aggregation of intact erythrocytes and specific binding of fibrinogen to the erythrocyte membranes. These results suggest that in addition to non-specific binding, a specific binding mechanism is also involved in fibrinogen-induced erythrocyte aggregation.
纤维蛋白原浓度升高和红细胞聚集是各种心血管疾病和脑血管疾病期间的重要危险因素。目前，纤维蛋白原诱导的红细胞聚集被认为是由非特异性结合机制引起的。然而，关于高血压期间红细胞聚集变化的已发表数据表明可能存在其他机制。因此，我们检验了纤维蛋白原的特异性结合参与红细胞聚集的假设。结果发现，俄勒冈绿488标记的人纤维蛋白原以1.3微摩尔的解离常数特异性结合大鼠红细胞膜。进一步的实验表明，肽Arg-Gly-Asp-Ser既能阻断纤维蛋白原诱导的完整红细胞聚集，又能阻断纤维蛋白原与红细胞膜的特异性结合。这些结果表明，除了非特异性结合外，特异性结合机制也参与了纤维蛋白原诱导的红细胞聚集。
