title: The initiation of fibrinolysis in alpha 2-plasmin inhibitor deficient plasma. Role of fibrin.
abstract: Plasmin activity and fibrin degradation products (FDP) are found in alpha 2-plasmin inhibitor (alpha 2-PI) deficient plasma only when clotted, but are not found when the plasma is not clotted. To determine whether fibrin itself could initiate fibrinolysis without activating coagulation enzymes, fibrin monomers were prepared and added to alpha 2-PI deficient plasma. The addition of fibrin monomers resulted in the generation of plasmin activity, a marked increase in FDP concentration, and the release of 125I from 125I-labeled fibrin monomers. Replenishment of the deficient plasma with purified alpha 2-PI abolished the effects of fibrin monomers on the initiation of fibrinolysis. Neither development of plasmin activity, increase of FDP, nor release of 125I was observed. These findings indicate that fibrinolysis can be induced by fibrin itself without activation of coagulation cascade and the induction of fibrinolysis is efficiently blocked by alpha 2-PI.
mesh_terms: D001777:Blood Coagulation; D005337:Fibrin / Q000502:physiology*; D005338:Fibrin Fibrinogen Degradation Products / Q000378:metabolism; D005341:Fibrinolysin / Q000378:metabolism; D005342:Fibrinolysis; D006801:Humans; D007457:Iodine Radioisotopes; D007700:Kinetics; D010958:Plasminogen / Q000378:metabolism; D000979:alpha-2-Antiplasmin / Q000502:physiology*
chemical_list: D005338:Fibrin Fibrinogen Degradation Products; D007457:Iodine Radioisotopes; D000979:alpha-2-Antiplasmin; D005337:Fibrin; D010958:Plasminogen; D005341:Fibrinolysin