NAC对染尘大鼠模型血清及肺组织中丙二醛的影响

目的探讨N-乙酰半胱氨酸(NAC)对二氧化硅所致大鼠肺纤维化血清及肺组织中丙二醛(MDA)的影响。方法取健康、雄性Wistar大鼠90只,随机分为3组:染尘组:采用经非暴露气管注入法,气管内注入无菌SiO2粉尘悬液(50 mg/ml)1 ml建立矽肺模型;4周后再次予以染尘1次。NAC预防治疗组:模型制备同染尘组,于染尘前1周及此后每日予以NAC[500 mg/(kg.d)]灌胃;对照组:同样条件下向气管内注入等量生理盐水。3组动物于实验第8周处死,取肺组织标本行病理学观察、测定肺组织及血清中MDA水平。结果染尘组及预防治疗组MDA含量明显高于对照组;预防治疗组MDA的含量明显低于染尘组,差异有统计学意义(P0.01)。结论 NAC可降低SiO2所致肺纤维化大鼠MDA的产生,抑制肺纤维化的发展,减轻对肺组织的损伤。

Effect of NAC on serum and lung tissue MDA in model of silica-exposed rats

[Objective]To investigate the effect of N-acetylcysteine(NAC) on serum and lung tissue MDA in model of silica-exposed rats with pulmonary fibrosis.[Methods]A total of 90 male rats were randomly categorized into silica-exposed group(3 group),Dust exposure group: the silicosis model was established via intratracheal instillation of sterile SiO2 dust suspension by non-exposed tracheal injection method;the dust exposure was repeated after 4 weeks.N-acetylcysteine treated group(N group) and control group(C group).Except the C group,other rats received instilling SiO2.S group was fed on NAC [500 mg/(kg ·d)] one week before silica exposure.C group was instilled by normal saline instead of SiO2.All the rats in each group were sacrificed at the 8th week of experiment.Histopathological examination was performed,the level of MDA in serum and lung tissue was observed.[Results]The level of MDA in serum and lung tissue of S group was significantly higher than that of C group(P<0.01).The level of MDA of N group was significantly lower than that of S group(P<0.01).[Conclusion]The MDA generation in rat with SiO2-induced pulmonary fibrosis can be reduced by NAC which can inhibit the development of lung fibrosis and can reduce lung tissue damage.