Is a Cofactor for Activated Protein C Neutralization of an Inhibitor of Plasminogen Activation Released From Platelets
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چکیده
Platelets stimulated with thrombin release an inhibitor of plasminogen activator (PAl). which has been shown previously to be neutralized by activated protein C (APC). The requirements for optimal neutralization of PAl activity were investigated. The releasate of gel-filtered human platelets stimulated with thrombin served as a source of PAl. When 6 x i08 platelets/mi were incubated with thrombin (1 lU/mi). the releasate contained 18 to 26 ng/mi PAl as determined by incubation of the releasate with urokinase and measurement of residual urokinase activity on plasminogen (52251 ). Preincubation of PAl with up to 4 pg/mi APC for two hours yielded less than 20% neutralization of PAl activity. In the presence of protein S. phospholipid, and Ca2 . neutralization of PAl activity was
منابع مشابه
Protein S is a cofactor for activated protein C neutralization of an inhibitor of plasminogen activation released from platelets.
Platelets stimulated with thrombin release an inhibitor of plasminogen activator (PAI), which has been shown previously to be neutralized by activated protein C (APC). The requirements for optimal neutralization of PAI activity were investigated. The releasate of gel-filtered human platelets stimulated with thrombin served as a source of PAI. When 6 X 10(8) platelets/mL were incubated with thro...
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