History of coagulation

Antivitamin K

Factor VII and Protein C are the first factors decreased by the antivitamin K treatment (half-life : 4-6 hours).

Blood Platelets

In 1883, G. Hayem, a French biologist showed that puncture wounds in a mesenteric vein of a frog were occluded by white thrombus. About the same time, Bizzozero was the first author to use the term «blood platelets».


The name of Warfarin is a partial acronym for the Wisconsin Alumni Research Foundation, while Coumarin (4-hydroxycoumarin) is the form most generally prescribed.

Haemorrhagic familial syndrome

Von Willebrand had first described in 1926 a haemorrhagic familial syndrome, inherited in a dominant manner, in a small ethnic group of Aaland islands, located in the Baltic sea, between Sweden and Finland.

Protein C

In 1976, Stenflo purified and partially characterised protein C. During his isolation procedure, Stenflo obtained four peaks in his chromatography elution steps. These peaks where labelled sequentially A through D; the third peak contained a «new» protein has been called arbitrarily protein C.

Antihaemophilic factor

In 1953, Dr R. Langdell et al. proposed a plasma clotting test that could be used for assaying antihaemophilic factor. They designated their one-stage test as "partial thromboplastin time".

Calcium Role in Coagulation

The role Calcium plays in coagulation was discovered in 1890 by Arthur and Pages.


Heparin was discovered independently in 1911 by Doyon and in 1916 by McLean, for different reasons. The effect of heparin on blood clotting, however, had been observed one-third of a century earlier.

Various aspects of platelet function

Dr J.R. O'Brien devised methods of measuring various aspects of platelet function and was one of the first to report that aspirin inhibits aggregation.

Activation of factor IX

In 1977, with Bjarne Østerud, Dr. S.I. Rapaport described the activation of factor IX by factor VIIa/tissue factor complex as an additional pathway in the initiation of blood coagulation.