Haemostasis can be compared to a balance
A careful equilibrium between coagulation factors (activators) and anti-coagulation factors (inhibitors: Antithrombin, Protein C, Protein S) maintains blood fluidity. Any upset in this equilibrium will upset this balance resulting in either:
- Thrombosis: the formation of a clot in the case of a deficiency of an inhibitor,
- Haemorrhage: bleeding may be caused by a factor deficiency
Venous thrombosis is a common disease and it is estimated that 159 people in every 100,000 are affected each year. Clots in veins are the most frequent, but the major risk is when these break up and block blood flow in the lungs (pulmonary embolism). Because of the danger associated with this type of disease, a number of experimental models have been created to study the effect of antithrombotic drugs. The following model system has been used to visualize the formation of a thrombus by the haematology department at the faculty of Pharmacy in Bordeaux, France.