The Effect of Platelets Upon Factor Xa - Catalyzed Activation
نویسندگان
چکیده
The authors have investigated the ability of platelets to enhance factor Xa-catalyzed activation of factor VII. Unstimulated platelets were without effect, whereas freeze/ thawed platelets substantially enhanced activation. Antifactor V antibodies did not diminish the enhancement. Platelets activated by thrombin. collagen, or calcium ionophore A23187 also enhanced factor Xa-catalyzed activation of factor VII. In contrast to their lack of effect upon freeze/thawed platelets. antifactor V antibodies abolished augmented factor VII activation induced by activated platelets. Adding exogenous factor Va to unstimulated platelets failed to enhance factor Xa-catalyzed activation of factor VII, nor did adding exogenous factor Va to activated platelets augment activation beyond that observed with activated platelets alone. These observations can be interpreted as follows: (1 ) factor Va does not function as a
منابع مشابه
The effect of platelets upon factor Xa-catalyzed activation of factor VII in vitro.
The authors have investigated the ability of platelets to enhance factor Xa-catalyzed activation of factor VII. Unstimulated platelets were without effect, whereas freeze/thawed platelets substantially enhanced activation. Antifactor V antibodies did not diminish the enhancement. Platelets activated by thrombin, collagen, or calcium ionophore A23187 also enhanced factor Xa-catalyzed activation ...
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