Factor XIIa
Synonyms
Activated Factor XII
Activator, Prekallikrein
Blood Coagulation Factor XII, Activated
Coagulation Factor XIIa
Factor XII, Activated
Factor XIIa, Coagulation
Fragments, Hageman-Factor
Hageman Factor Fragments
Hageman-Factor Fragments
Prekallikrein Activator
XIIa, Coagulation Factor
Activated form of factor XII. In the initial event in the intrinsic pathway of blood coagulation, kallikrein (with cofactor HIGH MOLECULAR WEIGHT KININOGEN) cleaves factor XII to XIIa. Factor XIIa is then further cleaved by kallikrein, plasmin, and trypsin to yield smaller factor XII fragments (Hageman-Factor fragments). These fragments increase the activity of prekallikrein to kallikrein but decrease the procoagulant activity of factor XII.
See Also