How do anticoagulants prevent clotting of blood?
1 Answer
Anticoagulants are chemical substances that prevent or reduce coagulation of blood, prolonging the clotting time.
Explanation:
Anticoagulants inhibit the coagulation cascade by clotting factors that happens after the initial platelet aggregation. They generally include vitamin K antagonists, heparins and novel oral anticoagulants. All of these have different ways of working.
Vitamin K inhibitors prevent the formation of blood clots by reducing the production of factors II, VII, IX, and X as well the anticoagulant protein C and S by the liver. The production of these factors by the liver are dependent on adequate amounts of vitamin K. Vitamin K inhibitors reduce the production of these factors because it antagonises vitamin K.
Heparins and low molecular weight heparins prevent clotting of blood by blocking the action of two of the 12 clot-promoting proteins in the blood and factors II and X.
Thrombin inhibitors block the action of thrombin thus reducing the ability of blood to clot.
Factor Xa inhibitors block the action of the factor Xa which is important in the coagulation cascade. This reduces the ability of blood to clot.
