N-乙酰半胱氨酸对大鼠慢性支气管炎与肺气肿形成影响的实验研究

目的研究抗氧化剂N-乙酰半胱氨酸（NAC）对大鼠慢性支气管炎（CB,chronic bronohi-tis）与肺气肿形成的影响。方法24只健康雄性Wistar大鼠用完全随机设计随机分为4组,A组（假吸烟组）（n=6）、B组（慢性支气管炎并肺气肿组）（n=6）、C组（NAC预防组）（n=6）、D组（NAC治疗组）（n=6）,B、C及D组采用两次气管内注入脂多糖（LPS）及烟熏4周法制备慢性支气管炎并肺气肿大鼠模型,C组均在烟熏及气管内注入脂多糖前每天给予NAC（50mg/只）灌胃,D组在第15~28天烟熏前每天给予NAC（50mg/只）灌胃。各组对肺组织行HE染色观察肺泡面积改变。结果B组小气道均存在纤毛损伤、上皮细胞变性坏死糜烂脱落、黏液杯状细胞增生、气道管壁黏膜充血水肿、管壁炎性细胞浸润（淋巴细胞、中性粒细胞、单核细胞）（P〈0.05）,B组每只大鼠平均肺泡面积比A组增大（P〈0.05）,均符合慢性支气管炎并肺气肿的病理改变。C组及D组与B组比较：给予NAC防治的C组及D组小气道炎症减轻（P〈0.05）,则其肺泡面积减小（P〈0.05）,C组与A组比较肺泡面积差异无统计学意义（P〉0.05）,说明C组肺气肿不明显,与A组比较D组大鼠仍有一定程度的肺气肿（P〈0.05）。结论NAC抗氧化可抑制由吸烟及脂多糖诱导的大鼠慢性支气管炎并肺气肿的小气道炎症、拮抗小气道损伤及防治肺气肿形成。

The experimental study on effect of antioxidant on formation of chronic bronchitis and emphysema in rats

Objective The purpose of the present study was to investigate the effect of N-acetylcysteine(NAC)on formation of chronic bronchitis and emphysema in rats.Methods 24 healthy Wistarmale rats were divided into 4 groups randomly.Group B(CB and emphysema),Group C(NAC prevention)and Group D(NAC treatment)were instilled intratracheally with LPS twice and exposed to cigarette smoking 4 weeks to induce CB and emphysema model.Group C were administrated with NAC 50 mg every rat before given LPS and smoking.Group D were administrated with NAC 50 mg every rat from the 15th to the 28th day before given smoking.The morphology changes of alveoli area have been observed.Results Compared with group A,there were injury of cilium,necrosis and erosion of epithelium,proliferation of goblet cells,mucous hyperemia and edema,inflammatory cells infiltration in the tubal walls(including lympholeukocyte,neutrophil and monocyte)in group B,and meanwhile the average area of alveolus in group B increased(P<0.05).Consistent with pathological change of chronic bronchitis and emphysema in group B.Compared with group B,the inflammatory pathological change was reduced in group C and group D,and at the same time the average area of alveolus in group C and group D with the treatment of NAC reduced(P<0.05).Compared with group A,group C with the precautionarly treatment of NAC almost had not develop emphysem(P>0.05).group D with the treatment of NAC had emphysema to some extent Conclusion NAC can attenuate the inflammation and injury in small airways of chronic bronchitis and emphysema in rats induced by smoking and LPS.At the same time NAC can prevent the formation of emphysema in rats induced by smoking and LPS.