Induction of heme oxygenase-1 (HO-1) in blunt trauma-associated pulmonary hemorrhage

Inflammatory response, decomposition of extravascular hemoglobin (exvHb), and oxidative stress in pulmonary hemorrhage were monitored in rats subjected to lung blunt trauma (LBT), by exposure to blast overpressure wave of magnitude 112+/-10 kPa. LBT caused a 5-fold increase in blood neutrophil count, which was accompanied by 1.6-fold and 17-fold increases in the expression of CD11b, a cell adhesion molecule, and HO-1, an antioxidative protein, respectively. Accumulation of neutrophils and macrophages, deposition of exvHb, and increase in parenchymal HO-1, transferring (TRF), myeloperoxidase (MPO) were observed in hemorrhagic lesions. These alterations were accompanied by increases in TRF-bound [Fe3+] (8.2+/-2.3 muM vs. 0.4+/-0.1 muM in controls) and non-TRF complexes of [Fe3+] (4.5+/-1.8 muM vs. < 0.3 muM in controls), and formation of 3-nitrotyrosine within proteins in lung. Augmentation of free radical species, determined in a range of g = 1.97 through g = 2.08, was slight and insignificant.