Effect on Coagulation Time of Oral Administration of Rabbit Thrombin

Abstract

Parfentjev 1 recently described a method for the preparation of pseudoglobulin of rabbit plasma having a high clot-promoting activity. Parfentjev's preparation has been repeated and the activity associated with this pseudoglobulin was found to be thrombic in nature. 2 This was indicated by the ability of the pseudoglobulin fraction to coagulate pure fibrinogen solution in the absence of calcium and to coagulate citrated and oxalated plasma from which pro-thrombin had been removed. Evidence indicating that this material may have clinical applications as a powerful hemostatic when applied locally to small wounds has also been presented. 3

The present communication reports the effect of the oral administration of relatively large amounts of pseudoglobulin from rabbit plasma, hereafter referred to as “rabbit thrombin”, to dogs, normal subjects and patients suffering from hemophilia.

Methods. Coagulation times were determined on venous blood by the standard procedure formerly described. 4 In certain instances the blood was removed with an oiled syringe and determinations made both in glass tubes and in tubes made of a synthetic plastic “Lusteroid”. This procedure prolongs the coagulation time, 5 which makes it possible to evaluate small changes in the coagulation time in glass. In the case of the animal experiments the thrombin was administered either in hamburg steak or milk or in aqueous solution by stomach tube. In the case of human subjects 10 g of the material were dissolved in tomato juice and ingested.

Results. The investigations were carried out on 2 dogs. 2 normal human individuals and 2 patients suffering from hemophilia. When amounts of thrombin varying from 3 to 10 g were given to dogs by mouth there was a prompt fall in the coagulation time, reaching its maximum in about 2 hours, after which it returned toward its initial value.