Regulation of Glycoprotein IIB/IIIA Exposure on Platelets Stimulated With a-Thrombin
نویسنده
چکیده
Previous studies have shown that binding sites for fibrinogen on platelets stimulated with platelet-activating factor (PAF), adenosine diphosphate or epinephrine rapidly close in the absence of fibrinogen. In the present study we investigated whether a-thrombin induced similar changes in the glycoprotein (GP) IIB/IIIA-complex. Whereas 80% of binding sites exposed by PAF closed within 30 minutes (22°C). a-thrombin (0.1 U/mL) triggered long-lasting exposure of binding sites for ['251]-fibrinogen and ['251]-fibronectin. Even removal of a-thrombin with an excess of hirudin failed to close the binding sites. Similar to PAF, a-thrombin-exposed sites rapidly closed after addition of the protein kinase C inhibitor
منابع مشابه
Regulation of Glycoprotein IIB/IIIA Exposure on Platelets Stimulated With a-Thrombin
Previous studies have shown that binding sites for fibrinogen on platelets stimulated with platelet-activating factor (PAF), adenosine diphosphate or epinephrine rapidly close in the absence of fibrinogen. In the present study we investigated whether a-thrombin induced similar changes in the glycoprotein (GP) IIB/IIIA-complex. Whereas 80% of binding sites exposed by PAF closed within 30 minutes...
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