LAUSR

ObjectiveTo observe the effect of electroacupuncture (EA) on the expressions of acetylcholine (ACh) and mucin 5AC (MUC5AC) in the lungs of rats with chronic obstructive pulmonary disease (COPD), and explore the mechanism of EA in treating COPD.MethodsThirty Sprague-Dawley (SD) rats were randomly divided into a control group, a COPD group, and an EA group, with 10 rats in each group. The control group was a group of normal rats. The COPD rat model was induced by cigarette smoke combined with lipopolysaccharide (LPS). The COPD rats were treated with EA at bilateral Feishu (BL 13) and Zusanli (ST 36) in the EA group, 30 min each time, once a day, successively for 14 d. The lung function was tested. The contents of ACh and MUC5AC in lungs and bronchoalveolar lavage fluid (BALF) were detected by enzyme-linked immunosorbent assay (ELISA). Pearson method was used to analyze the correlation between pulmonary function and the content of MUC5AC in lungs. The mRNA and protein expressions of MUC5AC in lung tissues were detected by real-time polymerase chain reaction (RT-PCR) and Western blot (WB), respectively. The immune response of MUC5AC was observed by immunohistochemistry.ResultsEight rats were left in each group, and the other two died. Compared with the control group, the total airway resistance (Raw) increased significantly and dynamic compliance (Cdyn) decreased significantly in the COPD group (P<0.01); compared with the COPD group, the Raw level declined significantly and Cdyn increased significantly in the EA group (P<0.01). The contents of ACh and MUC5AC in the lungs and BALF were remarkably higher in the COPD group compared with those in the control group (P<0.01, P<0.001); compared with the COPD group, the contents of ACh and MUC5AC were significantly lower in the EA group (P<0.05, P<0.001). There was a negative correlation between MUC5AC content and lung function (P<0.001). The mRNA and protein expressions of MUC5AC in the lungs were significantly higher in the COPD group than in the control group (P<0.001); compared with the COPD group, the expressions were significantly lower in the EA group (P<0.01). Compared with the control group, the immune response of MUC5AC in the airway epithelium significantly increased in the COPD group (P<0.001); the immune response of MUC5AC was significantly lower in the EA group compared with that in the COPD group (P<0.001).ConclusionEA treatment can improve the lung function of COPD rats, which may be related to its effect in the down-regulation of ACh and MUC5AC contents in the lungs as well as the inhibition of mucus hypersecretion.摘要目的观察电针对慢性阻塞性肺疾病(COPD)大鼠肺中乙酰胆碱(ACh)及黏蛋白5AC(MUC5AC)表达的影响, 探讨针刺治疗COPD的作用机制。方法将30只Sprague-Dawley (SD)大鼠随机分为对照组、COPD组和电针组, 每组10 只。采用香烟烟雾联合脂多糖诱导方法制备COPD模型。电针组大鼠予以电针双侧肺俞和足三里, 每日1次, 每次 30 min, 连续治疗14 d。干预结束后检测肺功能, 应用ELISA法检测肺组织及支气管肺泡灌洗液(BALF)中ACh及 MUC5AC的含量, 采用Pearson法分析肺功能与MUC5AC含量的相关性, 实时聚合酶链反应(RT-PCR)检测肺组织 MUC5AC mRNA的表达, 蛋白免疫印迹(WB)及免疫组化方法检测MUC5AC的蛋白表达及免疫反应性。结果每组均有2只大鼠死亡, 剩余8只。与对照组比较, COPD组总气道阻力(Raw)显著升高且动态顺应性(Cdyn)显著降低 (P<0.01); 与COPD组比较, 电针组Raw显著下降, Cdyn显著升高(P<0.01)。与对照组比较, COPD组大鼠肺组织及 BALF中ACh及MUC5AC含量均显著升高(P<0.01, P<0.001); 与COPD组比较, 电针组ACh及MUC5AC含量均显著降低(P<0.05, P<0.001)。肺功能与MUC5AC含量呈负相关(P<0.001)。与对照组比较, COPD组大鼠肺组织中MUC5AC 的mRNA及蛋白表达均显著升高 (P<0.001); 与COPD组比较, 电针组MUC5AC的mRNA及蛋白表达均显著下降 (P<0.01)。与对照组比较, 气道上皮MUC5AC免疫反应活性显著升高(P<0.001); 与COPD组比较, 电针组气道上皮 MUC5AC免疫反应活性显著下降(P<0.001)。结论电针可改善COPD大鼠肺功能, 其机制可能与电针下调肺组织中ACh及MUC5AC的表达及降低气道黏液高分泌有关。