E-cadherin与PCNA在吸烟小鼠气道上皮中的表达

应用免疫组织化学和原位分子杂交方法，检测不同阶段吸烟小鼠细支气管上皮细胞上皮钙粘附素（Ｅ－ｃａｄ－ｈｅｒｉｎ，Ｅ－ｃｄ）和增殖细胞核抗原（ＰＣＮＡ）的表达与分布。探讨吸烟气道Ｅ－ｃｄ表达变化对上皮增殖、重建的影响。结果：小鼠吸烟４周时，细支气管上皮Ｅ－ｃｄ表达与正常对照组比较明显下调，而ＰＣＮＡ阳性细胞率明显高于正常对照组（Ｐ＜０．０１）；吸烟８周时，Ｅ－ｃｄ表达上调，而ＰＣＮＡ表达比吸烟４周时明显减少；吸烟１２周时，Ｅ－ｃｄ与ＰＣＮＡ表达阳性细胞率与吸烟４周时相比均明显减少（Ｐ＜０．０１）。而各组间的细支气管上皮细胞内的Ｅ－ｃｄｍＲＮＡ含量及表达强度均无明显变化。结论：吸烟引起气道上皮Ｅ－ｃｄ表达的调控发生在翻译后水平，其胞膜上Ｅ－ｃｄ表达的下调在吸烟早期气道上皮损伤后修复中发挥重要作用。

E-cadherin and PCNA Expression on Airway Epithelium in Smoking Mice

Immunohistochemistry and hybridization in situ technique were used to detect Ecadherin (Ecd) and proliferating cell nuclear antigen (PCNA) expression and distribution on epithelial cells of bronchioles in smoking mice of different stages to investigate the effects of Ecd expression change on epithelial proliferation and reconstruction in smoking mice The results showed that 4 weeks after smoking, the Ecd expression in epithelium of mice bronchioles was downregulated as compared with the normal control group, and percentage of postive cells of PCNA was significantly higher than that in normal control(P<001) Eight weeks after smoking, Ecd expression was upregulated and PCNA expression was significantly lower than that after smoking for 4 weeks Twelve weeks after smoking, percentage of postive cells of Ecd and PCNA was significantly lower than that after smoking for 4 weeks(P<001). But the content and staining intensity of Ecd mRNA were not obviously changed in the epithelial cells of bronchoiles among the different groups It is concluded that Ecd expression is regulated at the posttranslational level. The down regulation of membranous Ecd expression plays an important role in the repair after the injury of airway epithelial cells at early stage of smoking