p38 MAPK expression in airway and lung tissue in acute lung injury rat model and influence of antioxidant NAC

    ZHANG Jian, LI Shengª²Qing, QI Haoª²Wen, WU Changª²Gui, LI Huanª²Zhang

    Department of Respiratory Medicine, Xijing Hospital, Fourth Military Medical University, Xi¡¯an 710033, China

    ¡¾Abstract¡¿ AIM: To observe the in situ phosphated expression of p38 MAPK in lung tissues of acute lung injury rat model induced by Lipopolysaccharide (LPS). METHODS: We used immunohistochemical ABC and Westernª²blot method to detect the expression of p38 MAPK in lung tissues and airway epithelial cells in acute lung injury rat model and observed the influence of Nª²acetylcysteine (NAC) on the expression. RESULTS: There were rare p38 MAPK positive cells scattered in alveolar and airway epithelial cells in the control group (P<0.01). The positive p38 MAPK cells in LPS injury groups increased obviously than those in the control groups (P<0.01), and were mainly distributed in infiltrative inflammatory cells, airway epithelial cells, alveolar epithelial cells and pleura mesepithelial cells. In NAC treatment group, the p38 MAPK positive cells in airway and lung tissue were much less than those in the acute lung injury group (P<0.05). The Westernª²blot results were consistent with those of immunohistochemical method. CONCLUSION: p38 MAPK expression increases in alveolar and airway epithelial cells in LPS induced acute lung injury rat models. The activation of p38 MAPK is found in most lung tissues, suggesting that p38 MAPK participates in the signal transduction in inflammatory and noninflammatory cells. NAC is an effective antioxidant, which relieves the inflammation in acute lung injury rats, possibly through the inhibition of p38 MAPK activation. ......