Thromboplastic activity

Blocompatibillty - Thrombogenlclty. Blood coagulation (thromboplastic activity) can be initiated in two ways, as shown in Figure... 

Thus, if the water-soluble fraction is absorbed on tricalcium phosphate and then centrifuged, the supernatant contains a platelet factor referred to as factor I. The tricalcium phosphate pellet contains another factor called factor II, which can be eluted with 0.2% m sodium citrate. Factor II accelerates the conversion of fibrinogen to fibrin by thrombin. Factor III has thromboplastic activity and reverses the anticoagulant effect of heparin, and platelet thromboplastin, or factor IV, reacts with plasma components on active thromboplastin. At least two other factors have been described in platelets—serotonin and fibrinogen that coagulates under the influence of thrombin. Available evidence suggests that fibrinogens in plasma and pate-lets are identical. 

Purification and identification of brain phospholipids associated with thromboplastic activity. 

Heparin was discovered in 1916 by a medical student at Johns Hopkins University. While attempting to extract thromboplastic substances from various tissues he discovered a substance with powerful anticoagulant activity. This was named heparin because it was first extracted from the fiver. 

Kinjo M, Oka K, Naito S, Kohga S, Tanaka K, Oboshi S, Hayata Y, Yasumoto K (1979) Thromboplastic and Librinolytic Activities of Cultured Human Cancer Cell Lines. Brit J Cancer 39 15... 

---