Pericellular proteolytic cascade by plasmin/plasminogen activator system
- Author:
Matsuo OSAMU
- Publication Type:Journal Article
- From:
Chinese Journal of Pathophysiology
2001;17(8):766-
- CountryChina
- Language:Chinese
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Abstract:
Plasmin/plasminogen activators (PA) are the serine enzyme which digests fibrin and/or fibrinogen. Plasmin is produced by the cleavage of its precursor, plasminogen by PAs (urokinase-type PA and tissue-type PA). These events are expected in the thrmbolytic therapy for thromboembolic deseases. Apart from the blood fibrinolysis mentioned above, new role of plasmin/plasminogen activators has been extensively investigated in the field of cellular biology. On the cell surface, the receptor for urokinase-type PA (u-PAR) was found (that for t-PA has not cloned yet). Then, plasmin as well as u-PA itself activates pro-form of matrix metalloproteinases (MMPs) around the pericellular space. These proteolytic activities by u-PA, plasmin and MMPs induce the degradation of extracellular matrix (ECM), affording the cells certain enviroment for their biological function. Further, the coupling of u-PA/u-PAR system and integrins can generate intracellular signal transductions which take part in the regulation of cell proliferation, attachment or migration followed by various physiological and pathophysiological functions. These serial mechanisms are the principle of pericellular proteolytic cascade.