Clotting factors
From WikiLectures
Clotting factors are proteins that circulate in plasma in an inactive state. Their main function is to enable hemocoagulation (blood clotting). Most of them are produced by the liver.
| Factor | Name
Alternative name |
Function |
|---|---|---|
| I | fibrinogen | cleavage of several peptides produces monomeric fibrin, which further forms a fibrin network |
| II* | prothrombin | its active form (IIa) activates factors I, V, VII, VIII, XI, XIII, protein C and platelets |
| III | tissue thromboplastin
tissue factor |
factor VIIa cofactor |
| IV | Ca2+ | binding of coagulation factors to phospholipids |
| V | proaccelerin, labile factor, accelerating globulin | factor X cofactor – ensure the conversion of prothrombin into active thrombin |
| VI | older name for factor Va | – |
| VII* | proconvertin | activates factors IX, X |
| VIII | antihemophilic factor (AHF)
antihemophilic factor A - antihemophilic globulin (AHG) |
factor IX cofactor |
| IX* | The Christmas factor
plasma thromboplastin component (PTC) - antihemophilic factor B |
activates factor X |
| X* | Stuart-Prower factor** | activates factor II |
| XI | plasma precursor of thromboplastin
plasma thromboplastin antecedent (PTA) - antihemophilic factor C |
activates factor IX |
| XII | The Hageman factor
glass factor |
activates factor XI, VII and prekallikrein |
| XIII | fibrin stabilizing factor
Laki-Lorand factor |
|
| von Willebrand factor | binds to factor VIII, enables platelet adhesion | |
| high molecular weight kininogen (HMWK) Fitzgerald Factor | supports the mutual activation of XII, XI and prekallikrein | |
| prekallikrein (PKK)
Fletcher factor |
activates factor XII and prekallikrein, cleaves HMWK | |
| kallikrein | ||
| platelet phospholipids |
* vitamin K dependent
** named after the first two patients (Mr R. Stuart and Miss A. Prower) in whom factor X deficiency was described
Links[edit | edit source]
Related articles[edit | edit source]
Bibliography[edit | edit source]
- GANONG, William F. Přehled lékařské fyziologie. 20. edition. Galén, 2005. pp. 546–549. ISBN 80-7262-311-7.
- KITTNAR, Otomar. Lékařská fyziologie. 1. edition. Grada, 2003. 790 pp. ISBN 978-80-247-3068-4.
