The resistance of fibrin-stimulated tissue plasminogen activator to inactivation by a class PAI-2 inhibitor (minactivin).
Solid phase fibrin was an efficient stimulator of the tissue-type plasminogen activator (t-PA), and the plasmin produced could be detected by colorimetric assay of the soluble phase above the fibrin. However the fibrin-stimulated activity of t-PA was not inhibited by minactivin. This result was in contrast to that obtained with poly-D-lysine (PL) stimulated t-PA, where minactivin was a potent inhibitor. However, if PL was added to fibrin-bound t-PA, the enzyme once again became susceptible to minactivin inhibition. This occurred without release of t-PA from the fibrin matrix. Minactivin alone did not bind to fibrin or to the t-PA fibrin complex. It was therefore concluded that minactivin normally has no significant role in the regulation of t-PA mediated fibrinolysis, but this effect can be induced by PL.
D004347:Drug Interactions; D004789:Enzyme Activation / Q000187:drug effects; D005337:Fibrin / Q000494:pharmacology*; D005341:Fibrinolysin / Q000032:analysis; D005342:Fibrinolysis / Q000187:drug effects*; D006801:Humans; D010960:Plasminogen Activators / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D015849:Plasminogen Inactivators; D011107:Polylysine / Q000494:pharmacology; D010959:Tissue Plasminogen Activator / Q000037:antagonists & inhibitors / Q000502:physiology*
D015849:Plasminogen Inactivators; C039812:minactivin; D011107:Polylysine; D005337:Fibrin; D010960:Plasminogen Activators; D010959:Tissue Plasminogen Activator; D005341:Fibrinolysin