In Vitro Simulation of Thrombolysis Inhibition

Abstract

Hyperfibrinolysis is a serious clinical complication. The inhibitory concentrations 50% of antifibrinolytics were analyzed in the microtiter plate clot lysis assay, using 50 µL of plasma clots, 10 µL of antifibrinolytic drug, 10 µL of 354 IU/mL (final) urokinase, 4.46 µg/mL (final) tissue-type plasminogen activator or 0.6 mg/mL plasmin, and 50 µL of pooled normal plasma as clot supernatant. The inhibitory concentrations 50% of lysine against urokinase or tissue-type plasminogen activator is 2.0 or 4.2 mM, against ε-amino-caproic acid 0.7 or 1.5 mM, against tranexamic acid 0.03 or 0.17 mM, respectively. The inhibitory concentrations 50% of lysine, ε-amino-caproic acid, or tranexamic acid against plasmin is 7.4, 0.4, or 0.04 mM. The inhibitory concentrations 50% of aprotinin against urokinase or tissue-type plasminogen activator is about 60 KIU/mL, against plasmin 19 KIU/mL. Lysine might be a new antifibrinolytic drug with a clinically interesting rapid pharmacokinetic. This data help correct dosing of antifibrinolytics to patients with hyperfibrinolysis.