Previous studies have shown that angiotensin II stimulates the synthesis of plasminogen activator inhibitor-1 in cultured vascular cells, which suggests that activation of the renin-angiotensin system may impair fibrinolysis. We have investigated the effects of angiotensin II and of valsartan, a recently developed angiotensin II antagonist that is highly specific and selective for the angiotens...

Plasmin, the primary fibrinolytic enzyme, has a broad substrate spectrum and participates in other biological processes dependent upon proteolytic activity. Consequently, plasmin activity is tightly regulated by plasminogen activators and protease inhibitors. In this study, we examined whether regulation of plasminogen gene expression also might provide a new mechanism for controlling this syst...

Rabbits were immunized against the plasminogen activator released by SV4- virus-transformed hamster embryo cells. The resulting antiplasminogen activator immunoglobulin (APA-IgG) inhibited the enzymatic activity of the plasminogen activator produced by SV40-transformed hamster cells, and the plasmin-catalyzed release of these cells from the tissue culture dish. APA-IgG was not cytotoxic for t...

Matrigel, a basement membrane (BM) extract of the Engelbreth-Holm-Swarm (EHS) sarcoma, used in tumor invasion assays, was found to contain plasminogen. Plasminogen was identified, using Western blot analysis and casein zymograms, by comparison with human plasminogen. matrigel contained approximately 20-100 ng of plasminogen per 100 micrograms of protein as determined by these assays. Matrigel r...

Plasminogen is a circulating zymogen of plasmin, a primary fibrinolytic enzyme1}.Plasminogen binding to fibrin and vascular and blood cells increases the local concentration of the zymogenand accelerates the activation of plasminogen by plasminogen activators2). We have previously isolated a novel fungal triprenyl phenol, designed staplabin, which enhances plasminogen binding to fibrin and cult...

Plasminogen deficiency has emerged as a well-recognized disorder in which reduced levels of plasminogen lead to the development of pseudo membranes on mucosal surfaces, with subsequent end-organ damage of the affected tissue. Ligneous conjunctivitis is the most recognizable, well-documented, and common presentation of the clinical syndromes associated with plasminogen deficiency, although numer...

The role of plasminogen activator inhibitor-1 (PAI-1) in vascular smooth muscle cell (VSMC) apoptosis mediated by plasminogen activation was studied with the use of aorticVSMC derived from mice with deficiency of PAI-1 (PAI-1 (-/-) ), tissue-type (t-PA (-/-) ) or urokinase-type (u-PA (-/-) ) plasminogen activator or from wildtype (WT) mice with corresponding genetic background. Plasminogen incu...

Host-derived proteases are crucial for the successful infection of vertebrates by several pathogens, including the Lyme disease spirochete bacterium, Borrelia burgdorferi. B. burgdorferi must traverse tissue barriers in the tick vector during transmission to the host and during dissemination within the host, and it must disrupt immune challenges to successfully complete its infectious cycle. It...

Glucocorticoids decrease the plasminogen activator activity of rat hepatoma cells through production of an inhibitor. We have examined the dexamethasone regulation of plasminogen activator in anucleate rat hepatoma cells to investigate the role of the nucleus in the steroid regulation of this membrane-associated phenomenon. Dexamethasone did not affect either the intraor extra-cellular plasmino...