title: A comparison of the abilities of plasma kallikrein, beta-Factor XIIa, Factor XIa and urokinase to activate plasminogen.
abstract: In order to compare the relative potencies of plasma kallikrein, beta-Factor XIIa, Factor XIa and urokinase as plasminogen activators, plasminogen activation by these proteins was studied using a radiolabeled fibrin plate assay. Urokinase was approximately 20,000 times more active than kallikrein or Factor XIa and 300,000 times more active than beta-Factor XIIa. Kallikrein and Factor XIa were approximately equal in plasminogen activator activity and were 20 times more potent than beta-Factor XIIa.
mesh_terms: D010450:Endopeptidases / Q000494:pharmacology*; D005172:Factor XI / Q000494:pharmacology*; D005174:Factor XII / Q000494:pharmacology*; D015956:Factor XIIa; D015945:Factor XIa; D005337:Fibrin / Q000494:pharmacology; D006801:Humans; D007610:Kallikreins / Q000494:pharmacology*; D010446:Peptide Fragments / Q000494:pharmacology*; D010958:Plasminogen / Q000378:metabolism*; D014568:Urokinase-Type Plasminogen Activator / Q000494:pharmacology*
chemical_list: D010446:Peptide Fragments; D005174:Factor XII; D005337:Fibrin; D010958:Plasminogen; D005172:Factor XI; D010450:Endopeptidases; D007610:Kallikreins; D015945:Factor XIa; D015956:Factor XIIa; D014568:Urokinase-Type Plasminogen Activator