[Can ulinastatin be an effective inhibitor of human polymorphonuclear granulocyte elastase under severe stressed state?].

The inhibitory effect of ulinastatin (UST), an intrinsic human trypsin inhibitor was investigated on the activity of polymorphonuclear granulocyte elastase (PMNE) with or without alpha 1-protease inhibitor (alpha 1-PI) using the in vitro models. The results of the dodecyl-sulfate-electrophoresis (SDS-PAGE), indicated that splitting-action of crude granulocyte enzyme solution on the plasma fibronectin was inhibited by concentration-dependent UST of an equivalent value for treatment of stressed state. The PMNE-UST complex was competitively replaced by PMNE-alpha 1-PI complex in vitro models of inflammatory focus and circulation, hence UST was weaker than alpha 1-PI in its binding-affinity for PMNE. The PMNE activity was directly inhibited by UST in the inflammatory focus and circulation with or without alpha 1-PI.