Transition of pathophysiological significance of plasminogen activator inhibitor-From a chief player in antiinflammation, antifibrinolysis to that in the development of insulin resistance.

In the early phase of research, plasminogen activator inhibitor (PAI) was regarded as a negative regulator of fibrinolytic system, but the later study clarified that the changes in PAI level is closely related to risk factors of various pathologic processes of the lifestyle-related diseases. It is accepted that PAI-1 is a risk factor of the cardiovascular event in lifestyle-related diseases by recent researches analyzing the detailed function of PAI-1. In this review paper, we described the transition of pathophysiological significance of PAI based on many research papers especially from ours, which clarified the mechanism on protein expression of PAI, especially PAI-1.