目的探讨自噬-溶酶体系统在慢性阻塞性肺疾病(简称慢阻肺)大鼠骨骼肌萎缩中的作用机制。 方法采用单纯熏香烟法复制慢阻肺大鼠动物模型。采用Real time PCR,Western blot技术检测大鼠趾长伸肌中FOXO转录因子以及自噬相关基因Bnip3、Beclin1、p62、MAP-LC3Ⅱ/Ⅰ、Atg5的mRNA及蛋白表达,探讨自噬-溶酶体系统在慢阻肺大鼠骨骼肌萎缩中的作用机制,进一步探索骨骼肌萎缩的机制。用透射电镜观察对照组和实验组大鼠趾长伸肌组织切片及肺组织切片中的变化。 结果Real time PCR分析结果显示,实验组大鼠趾长伸肌组织中FOXO转录因子以及自噬相关基因Bnip3、Beclin1、p62、Atg5的mRNA表达实验组显著高于对照组(P均<0.05,其中Bnip3两组对照P均<0.01)。两组大鼠MAP-LC3Ⅱ/Ⅰ的mRNA表达比较差异无统计学意义(P>0.05)。Western blot分析结果显示,实验组大鼠趾长伸肌组织中FOXO转录因子以及自噬相关基因Bnip3、Beclin1、p62、MAP-LC3Ⅱ/Ⅰ、Atg5的蛋白表达慢阻肺组显著高于对照组(P均<0.05,其中Bnip3,MAP-LC3Ⅱ/Ⅰ、Beclin1两组对照P均<0.01)。透射电镜下,相比于对照组,实验组大鼠趾长伸肌胞浆内自噬溶酶体增多,肺组织切片中发现肺组织纤维化和炎症细胞增多。 结论实验组大鼠趾长伸肌组织内自噬-溶酶体系统被激活,可能是骨骼肌萎缩的机制之一
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