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目的:研究miRNA-222在失神经骨骼肌萎缩中的作用及机制。方法:取40只成年雄性SD大鼠，随机分为4组，假手术组、失神经骨骼肌萎缩组、失神经骨骼肌萎缩＋miRNA-222注射组和失神经骨骼肌萎缩＋anti-miRNA-222注射组。建立SD大鼠右下肢坐骨神经失神经骨骼肌萎缩动物模型。于术后4周行HE染色、腓肠肌肌湿重比和肌细胞直径检测，采用实时定量PCR检测各组miRNA-222的表达水平，采用实时定量PCR和Western blot法检测各组腓肠肌细胞中miRNA-222靶基因MyOD和Rbm24的mRNA及蛋白表达量。结果:术后4周，失神经骨骼肌萎缩组miRNA-222表达量显著增高；与假手术组相比，失神经骨骼肌萎缩组出现明显肌萎缩，外源性注射miRNA-222可使肌萎缩进一步加重，外源性注射anti-miRNA-222可有效减轻肌萎缩。与假手术组相比，失神经骨骼肌萎缩组MyOD和Rbm24 mRNA含量显著减少，外源性注射miRNA-222后MyOD和Rbm24 mRNA含量进一步减少，相反外源性注射anti-miRNA-222后MyOD和Rbm24 mRNA含量虽较假手术组低，但与失神经骨骼肌萎缩组及miRNA-222注射组相比MyOD和Rbm24 mRNA含量均有显著增高。蛋白检测结果与mRNA结果一致。结论:外源性miRNA-222可抑制MyOD和Rbm24的mRNA及蛋白表达水平，加重失神经骨骼肌的萎缩程度；相反，外源性anti-miRNA-222可有效对抗miRNA-222的作用，减轻失神经骨骼肌的萎缩程度。“,”Objective:To study the role and mechanism of miRNA-222 in denervated skeletal muscle atrophy.Methods:Forty adult male SD rats were randomly divided into four groups: sham operated group, denervated skeletal muscle atrophy group, denervated skeletal muscle atrophy+ miRNA-222 injection group and denervated skeletal muscle atrophy+ anti-miRNA-222 injection group. The animal model of denervated skeletal muscle atrophy in the right lower limb was established in SD rats. HE staining, detection of gastrocnemius muscle wet mass ratio and diameter of myocytes were performed 4 weeks after operation. The expression level of miRNA-222 was detected by real-time quantitative PCR, and the mRNA and protein expression of MyOD and Rbm24 were detected by real-time quantitative PCR and Western blot.Results:Four weeks after operation, the expression of miRNA-222 in the denervated skeletal muscle atrophy group was significantly increased. Compared with the sham operation group, the denervated skeletal muscle atrophy group appeared obvious atrophy, exogenous injection of miRNA-222 could further aggravate the atrophy, exogenous injection of anti-miRNA-222 could effectively reduce the atrophy. Compared with sham operation group, the MyOD and Rbm24 mRNA in denervated skeletal muscle atrophy group decreased significantly, and the MyOD and Rbm24 mRNA further decreased after exogenous injection of miRNA-222. On the contrary, the MyOD and Rbm24 mRNA after exogenous injection of anti-miRNA-222 was lower than that in sham operation group, but the MyOD and Rbm24 mRNA were significantly higher than those in the denervated skeletal muscle atrophy group and miRNA-222 injection group. The result of protein detection was consistent with that of mRNA.Conclusion:Exogenous miRNA-222 can inhibit the mRNA and protein expression level of MyOD and Rbm24, and aggravate the atrophy degree of denervated skeletal muscle; on the contrary, exogenous anti-miRNA-222 can effectively resist the effect of miRNA-222, and reduce the atrophy degree of denervated skeletal muscle.