Plasma Ac-globulin

The next series of transformations leads to thrombin formation. A precursor of thrombin, the familiar prothrombin whose synthesis in the liver requires vitamin K, combines with thromboplastin stoichiometrically. The reaction requires calcium and a platelet factor referred to as platelet factor 1. The product of the reaction is thrombin but prothrombin production by the mechanism just described is so slow that the process must be activated for efficient coagulation, and thrombin catalyzes its own production. Thus, thrombin converts a plasma component, factor 1, or the plasma AC globulin into an active catalyst capable of accelerating prothrombin conversion to thrombin. 

Ac-globulin thrombogen factor V labile factor component A of prothrombin prothrombin accelerator proacce-lerin accelerator factor plasma prothrombin conversion factor plasmatic cofactor of thromboplastin prothrom-binase... 

Globulins, Albumin and Plasma at Interfaces in "Applied Chemistry at Protein Interfaces", E. Baier Ed., Advances in Chemistry Series ACS Washington D.C. (1975). 

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