Plasminogen activator inhibitor 2 reduces peritoneal fibrinolytic activity in inflammation

Fibrinolysis in peritoneal tissue may play a role in the development of intra-abdominal adhesions. The plasminogen-activating capacity of human peritoneum results largely from the presence of tissue plasminogen activator (tPA). Inflammation reduces peritoneal plasminogen-activating activity and leads to the appearance of plasminogen activator inhibitor (PAI) type 1. The role of PAI-2 in the inhibition of peritoneal fibrinolysis during inflammation was investigated in this study. The plasminogen-activating activity of peritoneal biopsy homogenates (seven inflamed, seven normal), measured using a fibrin plate technique, was reduced in inflamed compared with normal tissue (median < 0.07 versus 13.9 units/cm2, P < 0.01); tPA antigen levels were not significantly different (median 1.02 versus 1.34 ng/ml). PAI-1 and PAI-2 antigens were not detected in normal human peritoneum but were present in inflamed peritoneum (median concentration 8.8 ng/ml for PAI-1, 26.7 ng/ml for PAI-2). These inhibitors may be important factors in adhesion formation by contributing to the abolition of peritoneal plasminogen-activating activity.