0List of Clotting Factors:
Factor I:
- Name: Fibrinogen.
- Source: Liver.
- Pathway: Both extrinsic and intrinsic.
- Activator: Thrombin.
- Actions: When fibrinogen is converted into fibrin by thrombin, it forms long strands that compose the mesh network for clot formation.
Factor II:
- Name: Prothrombin.
- Source: Liver.
- Pathway: Both extrinsic and intrinsic.
- Activator: Prothrombin activator.
- Actions: Prothrombin is converted into thrombin which then activated fibrinogen into fibrin.
Factor III:
- Name: Thromboplastin / Tissue factor.
- Source: Platelets (intrinsic) and damaged endothelium (cells) lining the blood vessel (extrinsic).
- Pathway: Both extrinsic and intrinsic.
- Activator: Injury to blood vessel.
- Action: Activates factor VII (VIIa).
Factor IV:
- Name: Calcium.
- Source: Bone and absorption from food in gastrointestinal tract.
- Pathway: Both extrinsic and intrinsic.
- Action: Works with many clotting factors for activation of the other clotting factors. These are called calcium-dependent steps.
Factor V:
- Name: Proaccerin / Labile factor / Ac-globulin (Ac-G)
- Source: Liver and platelets
- Pathway: Both extrinsic and intrinsic
- Activator: Thrombin
- Action: Works with Factor X to activate prothrombin (prothrombin activator).
Factor VI:
- Name: Proconvertin / Serum prothrombin conversion accelerator (SPCA) / stable factor.
- Source: Liver.
- Pathway: Extrinsic.
- Activator: Factor III (tissue factor).
- Actions: Activates Factor X which works with other factors to convert prothrombin into thrombin.
Factor VII:
- Name: Anti-hemoplytic factor / Antihemophilic factor (AHF) or globulin (AHG) / antihemophilic factor A.
- Source: Endothelium lining blood vessel and platelets (plug).
- Pathway: Intrinsic.
- Activator: Thrombin.
- Actions: Works with Factor IX and calcium to activate Factor X.
- Deficiency: Hemophilia A.
Factor VIII:
- Name: Christmas factor / Plasma thromboplastin component (PTC) / Antihemophilic factor B.
- Source: Liver.
- Pathway: Intrinsic.
- Activator: Factor XI and calcium.
- Actions: Works with Factor VIII and calcium to activate Factor X.
- Deficiency: Hemophilia B.
Factor IX:
- Name: Stuart Prower factor / Stuart factor.
- Source: Liver.
- Pathway: Extrinsic and intrinsic.
- Activator: Factor VII (extrinsic) / Factor IX + Factor VIII + calcium (intrinsic).
- Actions: Works with platelet phospholipids to convert prothrombin into thrombin. This reaction is made faster by activated Factor V.
Factor X:
- Name: Plasma thromboplastin antecedent (PTA) / antihemophilic factor C.
- Source: Liver.
- Pathway: Intrinsic.
- Activator: Factor XII + prekallikrein and kininogen.
- Actions: Works with calcium to activate Factor IX.
- Deficiency: Hemophilia C.
Factor XI:
- Name: Hageman factor.
- Source: Liver.
- Pathway: Intrinsic.
- Activator: Contact with collagen in the torn wall of blood vessels.
- Actions: Works with prekallikrein and kininogen to activate Factor XI. Also activates plasmin which degrades clots.
Factor XII:
- Name: Fibrin stabilizing factor
- Source: Liver
- Activator: Thrombin and calcium
- Actions: Stabilizes the fibrin mesh network of a blood clot by helping fibrin strands to link to each other. Therefore it also helps to prevent fibrin breakdown (fibrinolysis).
Prekallikrein:
- Source: Liver.
- Pathway: Intrinsic.
- Actions: Works with kininogen and Factor XII to activate Factor XI.
Kininogen:
- Source: Liver.
- Pathway: Intrinsic.
- Actions: Works with prekallikrein and Factor XII to activate Factor XI.
