Fibrinolytic enzymes in ascites during experimental acute pancreatitis in rats.

The ascites accumulating during acute pancreatitis contain proteases that play a role in the progression of this disease. The proteases of the fibrinolytic system in the ascites were therefore studied in experimental acute pancreatitis induced in rats. Synthetic substrate assay and the fibrin plate method revealed high activities of proteases, including plasminogen activator, in the ascites. The plasminogen activator had a mol wt of about 50,000 by zymography. The plasminogen activator adsorbed on Lys-sepharose from the ascites was observed at the 100,000 mol wt position and in the 50,000-100,000 mol wt range on zymography and appeared at the 50,000 mol wt position after treatment by concentration. Its activity was enhanced by trypsin treatment. In other experiments, when incubated homogenate of normal pancreas lacking in zymographic activity was injected intraperitoneally into healthy rats, the recovered fluid displayed lytic zones between the 100,00 and 50,000 mol wt positions. These findings suggest that the ascites contained plasminogen activator, part of which was released by intrapancreatic substances and was present in the precursor form.