Intravenous platelet activating factor does not affect lung epithelial permeability

Administration of platelet activating factor has been shown to produce lung edema in several species including the rabbit. To determine if platelet activating factor increases lung alveolar epithelial permeability, we studied the effect of intravenous platelet activating factor administration on clearance of ^99mTc-DTPA from the lung of the rabbit. Intravenous platelet activating factor produced marked hemodynamic and cellular responses but did not increase the clearance of ^99mTc-DTPA from lung to blood. We conclude that although platelet activating factor can induce lung edema in the rabbit, it does not produce an acute increase in alveolar epithelial permeability.