Stimulation of PAI-1 expression in endothelial cells by cultured vascular smooth muscle cells

Abstract

Regulation of endothelial cell (EC) plasminogen activator inhibitor type-1 (PAI-1), the primary physiological inhibitor of tissue-type plasminogen activator (TPA) and urokinase-type plasminogen activator (UFA), by various stimuli has been well characterized. We report the upregulation of secreted and intracellular PAI-1 in human umbilical ECs when cocultured with human smooth muscle cells (SMCs) on amniotic membranes or incubated with SMC conditioned medium (CM) under serum-free conditions as determined by enzyme-linked immunosorbent assay. Cocultured human umbilical vein ECs and SMCs, or human umbilical artery ECs and SMCs, displayed a 73% and 68% increase, respectively, in released PAI-1. ..