Nitroprusside has no effect on t-PA and PAI production and release by endothelial cells in culture

Summary In this study we examined the influence of sodium nitroprusside (SNP) on the fibrinolytic activity of human umbilical venous endothelial cells (HUVEC) and platelets. SNP (1–100 uM) was not able to modify tissue type plasminogen activator (t-PA) and its specific inhibitor (PAI-1) production by cultured endothelial cells. As already known, SNP dose-dependently inhibited platelet aggregation in response to several agonists. However, platelet PAI release measured during stimulation in the presence of SNP was not affected, even at concentrations of SNP able to block aggregation. Our data demonstrate that SNP has no effect on t-PA, and PAI production and release by human endothelial cells in culture; moreover, SNP does not affect PAI release from platelets in vitro.