LEUKOTRIENES IN THE PATHOGENESIS OF PULMONARY BLAST INJURY

Our previous studies demonstrate a significant increase of sulfidopept ide leukotriene concentrations in animals exposed to a free air blast, The aim of this study was to analyze the role of leukotrienes in the local response of lung tissue as well as in the general response of or ganisms to blast overpressure. The study was conducted on adult rabbit s exposed to moderate blast overpressure (four pulmonary contusions ch aracterized as confluent ecchymoses involving 30 to 60% of the lungs), generated in laboratory conditions, One group of experimental animals was treated with 5-lipoxygenase (5-LO) inhibitor, diethylcarbamazine (DEC, Sigma, St, Louis, Missouri) (50 mg/kg, i.v.), immediately before blast, The early posttraumatic period was observed (30 minutes after blast), Hemodynamic parameters (mean arterial pressure, heart rate, bl ood gases) as well as arterial plasma levels of conjugated dienes were observed, The myeloperoxidase activity, lipid peroxidation products l evels, and water contents were measured in the lung tissue of injured rabbits. We observed that 5-LO inhibition reduced edema formation, acc umulation of neutrophils, and generation of lipid peroxidation product s in injured lungs, In this study, we demonstrated that treatment with DEC inhibits the increased systemic generation of conjugated dienes a fter blast injury, Although DEC exerts local antioxidant activity with beneficial effects on lung tissue, this 5-LO inhibitor intensifies th e blast overpressure caused hemodynamic insufficiency.