Nitrotyrosine in otitis media with effusion

OBJECTIVES: Our purpose was to investigate mucosal cell injury due to the nitric oxide (NO)-superoxide system in otitis media with effusion. METHODS: We determined the levels of nitrotyrosine (NT) and NO and the activities of superoxide dismutase (SOD) and lactic dehydrogenase (LDH) in 90 middle ear fluid samples. RESULTS: The NT concentration was significantly higher in group A (<16 years old) than in group C (>50 years old; p < .05), and significantly higher in the acute group than in the chronic group (p < .05). The NO concentration did not show a significant difference among the groups. The activity of SOD showed significant correlations with the concentrations of NT and NO and with LDH activity (p < .05). The LDH activity was significantly greater in group A than in group C (p < .05). CONCLUSIONS: Our results indicate involvement of the NO-superoxide system in the pathogenesis of otitis media with effusion, showing evidence of protein and/or cell injury in the middle ear.