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PubMed · 2555642

Tissue plasminogen activator and plasmin independently decrease human neutrophil activation.

J L Mehta·P Mehta·D L Lawson·L Herzbrun
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Abstract

Tissue-plasminogen activator (t-PA) and plasmin both decrease platelet aggregation, which may contribute to thrombolysis and tissue salvage. Since neutrophils may contribute to reperfusion injury, we examined the effects of t-PA and plasmin on human neutrophil function. t-PA (1 to 100 micrograms/ml) decreased f-MLP-induced chemotaxis and ionophore A23187-induced superoxide and LTB4 release in isolated neutrophils, and these effects were not blocked by the plasmin-inhibitor epsilon-aminocaproic acid (epsilon-ACA). On the other hand, plasmin (0.05 to 0.5 units/ml) also decreased these neutrophil functions but its effects were blocked in the presence of epsilon-ACA. Thus, while both t-PA and plasmin decrease neutrophil functions, effects of t-PA are independent of plasmin generation. Cumulative effects of t-PA and plasmin on neutrophil functions may relate to the overall efficacy of t-PA in thrombotic disorders.

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CalcimycinChemotaxis, LeukocyteEpoprostenolFibrinolysinHumansIn Vitro TechniquesLeukotriene B4Lymphocyte ActivationNeutrophilsSuperoxidesTissue Plasminogen ActivatorJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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J L Mehta, P Mehta, D L Lawson, L Herzbrun. 1989. Tissue plasminogen activator and plasmin independently decrease human neutrophil activation.. https://doi.org/10.1016/0024-3205(89)90276-2

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