Coagulation factor II

Coagulation Factor II, also known as prothrombin, is a protein that plays a crucial role in the blood coagulation process, which is essential for stopping bleeding and initiating wound healing. This protein is synthesized in the liver and requires vitamin K for its production. Coagulation Factor II is a part of the coagulation cascade, a series of steps involving various proteins and enzymes, leading to the formation of a blood clot.

Structure and Function

Coagulation Factor II is a glycoprotein that is converted into its active form, thrombin, by the action of coagulation Factor X in the presence of coagulation Factor V, phospholipids, and calcium ions. Thrombin then plays a key role in converting fibrinogen, a soluble plasma protein, into fibrin, insoluble threads that form the scaffold of a blood clot. Besides its role in coagulation, thrombin also activates platelets and additional coagulation factors, promoting further clot formation.

Genetic and Molecular Aspects

The gene for Coagulation Factor II is located on chromosome 11 in humans. Mutations in this gene can lead to either an increase or decrease in prothrombin levels, affecting the blood's ability to clot. Elevated levels of prothrombin can increase the risk of thrombosis, while reduced levels can lead to hemophilia-like symptoms, including excessive bleeding.

Clinical Significance

Measurement of prothrombin levels, along with other tests like the Prothrombin Time (PT) and International Normalized Ratio (INR), is crucial in diagnosing and managing various bleeding disorders and in monitoring patients on anticoagulant therapy, such as warfarin. Prothrombin time specifically measures the time it takes for blood to clot, reflecting the activity of several coagulation factors, including Factor II.

Therapeutic Uses and Anticoagulation

In certain medical conditions, it may be necessary to inhibit the action of Coagulation Factor II to prevent the formation of unwanted blood clots. Anticoagulants such as direct thrombin inhibitors and warfarin work by inhibiting the action of thrombin or reducing the levels of vitamin K-dependent coagulation factors, including Factor II.

See Also

• Coagulation
• Blood clot
• Hemophilia
• Thrombosis
• Vitamin K