PAI-1 (Plasminogen activator inhibitor 1, Endothelial plasminogen activator inhibitor, Serpine 1, PAI, PLANH-1)

PAI-1 is the primary inhibitor of plasminogen activators in plasma. PAI-1 is a single-chain glycoprotein with a molecular weight of 47 kDa. It is synthesized in the liver and by endothelial cells, and its synthesis is regulated by several physiologic mediators including endotoxin, interleukin-1, fibroblast growth factor-2, and lipids. PAI-1 is an important inhibitor of the fibrinolytic system, therefore, elevated levels could suppress fibrinolysis and result in an increased risk of thrombosis.