RELEASE OF VONWILLEBRAND-FACTOR ANTIGEN (VWF-AG) AND EICOSANOIDS DURING ACUTE INJURY TO THE ISOLATED RAT LUNG

It has been suggested that the von Willebrand factor antigen (vWF:Ag) may be a clinical marker for pulmonary endothelial cell injury. An ELISA was developed for the measurement of rat VWF:Ag. Rat lungs were isolated and perfused with a recirculating, blood-free, physiologic salt solution. Circulating levels of VWF:Ag and the eicosanoids thromboxane B2 (TXB2) and prostaglandin 6-keto F1-alpha (6-keto PGF1-alpha) were measured before and after different forms of insult. The addition of phospholipase C (PLC) or hydrogen peroxide (H2O2) to the perfusate caused lung damage as manifested by pulmonary artery pressure increase and pulmonary edema. This was paralleled by significant release of vWF:Ag, TXB2, and 6-keto PGFI-alpha. Increased hydrostatic pressure caused pulmonary edema without vWF:Ag and ecosanoid release. The addition of vasopressin to the perfusate caused vWF:Ag release but no lung injury and no release of eicosanoids. It is concluded that in the rat model, vWF:Ag release is a nonspecific marker for lung injury.