Expression of MMP-9 in Rats with Phosgene-induced Acute Lung Injury

[Objective] To investigate the role of matrix metalloproteinase-9(MMP-9)in the pathogenesis of acute lung injury induced by phosgene.[Methods]Phosgene was produced by the decomposition of BTC in the catalysis of DMF,and the concentration of phosgene in the intoxication chamber was 8 mg/L.40 SD rats were randomly separated into 5 groups,the control group and the experiment groups(2,4,6,8 h after phosgene inhalation).Experiment rats were sacrificed at 2,4,6,8 h after phosgene inhalation.Wet to dry weight ratio of the lung(wet/dry)and the contents of protein in bronchoalveolar lavage fluid(BALF) were recorded,histopathology of the lung was observed under the light microscope,the expression of MMP-9 in lung tissue was verified by immunohistochemical analysis.[Results]Acute lung injury caused by phosgene was accompanied with increased expression of MMP-9 in lung tissues(P0.05),which was correlated with the elongation of time and aggravation of lung injury. [Conclusion]MMP-9 plays an aggravating role in the development of phosgene-induced acute lung injury in rats.