Thrombin, action, contact

However, Biirker has returned to this conception. According to him, coagulation of the blood is intimately related to the decomposition of the plates. All the conditions which influence thrombin, and consequently coagulation, such as temperature, contact, chemical products, act equally on the transformation of the plates. Sodium metaphosphate, magnesium sulphate, ammonium oxalate, all of which hinder coagulation, also preserve the blood components. This decomposition of the plates would take place under the action of a trypsin contained in the blood. Once these particles are destroyed, coagulation would appear. The quantity of fibrin formed is then in direct proportion to the... 

In circulating blood, the conditions indispensable for the production of this thrombin are not fulfilled. The throm-bokinase, retained inside the plates and the blood corpuscles, is not directly in contact with the other elements, for the contact efifect is lacking as a consequence of the viscous and slimy nature of the walls of the blood-vessels, and finally, the existence in the blood of anti-coagulating bodies opposes the action of the traces of thrombin which may nevertheless be formed. 

These facts are well established. The importance of each of these conditions can be experimentally shown and their exactness leaves no room for doubt. These are very positive results. But if now we ask in what order these different factors intervene in coagulation, by what means the action of calcium ions and that of contact is promoted, and in what state a preformed enzyme, or pro-enzyme, and the serozyme are found in the plasma, we are reduced to giving hypotheses in answer to these various questions. Without doubt, the theory as to how the serozyme and the thrombokinase combine, with the intervention of calcium ions and contact, to form active thrombin, explains in a satisfactory manner a whole series of experimental facts, but it must not be forgotten that here we are in the domain of pure speculation and that the agreement of all these facts could perhaps be explained by a different mechanism. However, thanks to the labors of Moravitz, Pekelharing, Bordet, and others,... 

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