Meconium induces formation of nitrotyrosine and expression of inducible nitric oxide synthase in the rat lung / 中国病理生理杂志

ABSTRACT

AIM: To evaluate the contribution of inducible nitric oxide synthase (iNOS) and nitrotyrosine to acute lung injury (ALI) in rats with meconium aspiration. METHODS: 16 health male Sprage-Dawley rats were randomized to control group and meconium group, followed by intratracheally administration of 1 mL/kg saline or 1 mL/kg 20% human newborn meconium suspension. The animals were killed after 24 h of treatment. The measurements included bronchoalveolar lavage fluid (BALF) cell count, pulmonary myoloperoxidase (MPO) activity and nitric oxide (NO) level. Western bloting was used to determine the expression of pulmonary nitrotyrosine-a specific “footprint” of peroxynitrite and iNOS. RESULTS: Compared to control group, the rats in the meconium group had increased BALF cell counts (4.04?1.01)?10~9cells/L vs (0.53?0.19)?10~9cells/L, pulmonary MPO activity (1.49?0.22)U/g wet lung tissue vs (0.62?0.16) U/g wet lung tissue, NO level (12.77?5.00) mmol/g protein vs (4.89?1.32) mmol/g protein, increased expression of nitrotyrosine and iNOS (0.46?0.19 and 1.49?0.60 vs 0.15?0.04 and 0.09?0.04, respectively), all P