摘要 : Plasminogen is the circulating zymogen of the broad spectrum serine protease, plasmin, the enzyme responsible for thrombus dissolution. In the mid 1980's it was first recognized that plasminogen also interacts with the surfaces of... 展开 Plasminogen is the circulating zymogen of the broad spectrum serine protease, plasmin, the enzyme responsible for thrombus dissolution. In the mid 1980's it was first recognized that plasminogen also interacts with the surfaces of cells. This interaction is functionally important because the plasminogen activators, urokinase;tissue plasminogen activator have, by themselves, a very limited capability to activate plasminogen. However, once the plasminogen activators bind to cellular receptors their ability to activate plasminogen is increased dramatically. The plasmin that is produced remains associated with the cell surface and is protected from inactivation by the plasmin inhibitor, a2-antiplasmin. This results in localization of the broad proteolytic activity of plasmin on cell surfaces, promoting the ability of cells to degrade extracellular matrices and activate other matrix-associated proteolytic enzymes and growth factors that facilitate cell migration. Thus, the interaction of plasminogen with cells plays a major role in macrophage recruitment during the inflammatory response, tumor cell invasion and metastasis, wound healing, tissue remodeling, neurite outgrowth;skeletal myogenesis. 收起