A Factor in Serum Which Accelerates the Conversion of Prothrombin to Thrombin: I. Its Determination and Some Physiologic
نویسندگان
چکیده
INTRODUCTION I N 1945, Nolf1 described a serum constituent, distinct from thrombin, which was capable of furthering coagulation. More recently, Ware et al. reported a substance, designated serum Ac globulin, which activates the conversion of prothrombin to thrombin by thromboplastin. Independently, Owren5 discovered a new clotting factor, ‘ ‘Factor VI,’ ‘ which arises during coagulation, speeds the evolution of thrombin, and catalyzes its own formation. These observations are of fundamental importance in our knowledge of blood clotting since they help explain the autocatalytic process underlying the evolution of thrombin. We observed that the admixture of serum to plasma accelerates the conversion of prothrombin to thrombin following the addition of thromboplastin plus calcium. This report presents data regarding some physiologic and biochemical properties of the agent (serum prothrombin conversion accelerator) responsible for this effect, together with a method for its estimation. A study of its role in blood coagulation and in the pathogenesis of certain hemorrhagic disorders is reserved for subsequent communications 6
منابع مشابه
A factor in serum which accelerates the conversion of prothrombin to thrombin; its determination and some physiologic and biochemical properties.
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A Factor in Serum Which Accelerates the Conversion of Prothrombin to Thrombin Ii. Its Evolution with Special Reference to the Influence of Conditions Which Affect Blood Coagulation
I N A PREVIOUS communication,’ a serum factor was described which accelerates the conversion of plasma prothrombin to thrombin by thromboplastin plus calcium, and a method for its determination was reported. This agent, labelled serum prothrombin conversion accelerator (SPCA), is distinct from thrombin, thromboplastin and labile factor. Insufficient data are available to establish the identity ...
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I N A PREVIOUS communication,’ a serum factor was described which accelerates the conversion of plasma prothrombin to thrombin by thromboplastin plus calcium, and a method for its determination was reported. This agent, labelled serum prothrombin conversion accelerator (SPCA), is distinct from thrombin, thromboplastin and labile factor. Insufficient data are available to establish the identity ...
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The conversion of prothrombin to thrombin during normal coagulation proceeds with ever increasing velocity until at the moment of clotting, or shortly thereafter, thrombin evolution is explosive. This phenomenon, referred to as the "autocatalytic" nature of thrombin formation, remains unexplained. It is evident that abnormalities in this reaction may underlie the pathogenesis of certain hemorrh...
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