Plasminogen and Tissue-type Plasminogen Activator (PLG/tPA)

Plasminogen is a plasma glycoprotein and zymogen that, upon cleavage by tPA or urokinase-type plasminogen activator (uPA), becomes plasmin, a serine protease capable of degrading fibrin and other extracellular matrix proteins, thereby mediating fibrinolysis, tissue remodeling, and cell migration. Tissue-type plasminogen activator (tPA) is a 70 kDa serine protease found on vascular endothelial cells; it catalyzes the conversion of plasminogen to active plasmin, initiating fibrin clot breakdown but is tightly regulated by plasma inhibitors such as PAI-1 and alpha2-antiplasmin. Recombinant forms of tPA are used as thrombolytic agents for acute ischemic stroke and myocardial infarction but present significant risks if administered in patients predisposed to bleeding. Both molecules are targets of drugs that modulate the fibrinolytic pathway for therapeutic purposes.

Other names

PGPLGrtPAalteplasePLAT

tPA: Cleaves plasminogen to plasmin, which dissolves fibrin clots by hydrolyzing peptide bonds. Antifibrinolytic agent: Inhibition of plasmin through competitive inhibition (e.g., aminocaproic acid). Inhibitors (PAI-1, neuroserpin) bind and inactivate tPA.