目的　探索失肌皮神经与胸大肌部分移位重建屈肘后供受体肌内成熟型与胚胎型乙酰胆碱受体（ε-AChR和γ-AChR）的表达变化，旨在为其术后肌萎缩的防治提供新视角。   方法　将70只成年SD大鼠随机分为A组（正常组）；B1、B2组（肌皮神经切断2、4 周组）；C1、C2组（假移植术2、4 周组）；D1、D2组（胸大肌部分移位缝合至肱二头肌腱重建屈肘功能术2、4 周组），共7组，每组10只。称量肌重，HE染色后测量肌纤维横切面积，RT-PCR和Western blot技术检测ε-AChR和γ-AChR的mRNA与蛋白表达变化。  结果　与A组比较，B组大鼠跛行，觅食受限，肱二头肌（受体肌）湿重逐渐减轻，肌纤维横切面积减小，ε-AChR mRNA和蛋白表达下调，γ-AChR 出现重新表达并逐渐上调；C组中上述改变进行性加重，D组的上述改变逐渐恢复，且胸大肌（供体肌）内ε和γ-AChR仅一过性异常表达。  结论　大鼠失肌皮神经损伤后，行胸大肌部分移位重建屈肘功能术，能上调受体肌内ε-AChR表达和下调γ-AChR的表达而改善屈肘功能。

Objective　To explore the expression changes of acetylcholinereceptors（AChR）ε and γ subtypes (ε-AChR and γ-AChR) in the recipient muscle (biceps brachii) and donor muscle (oblique part of pectoralis major) after musculocutaneous nerve transection and elbow flexion reconstruction, and to provide a scientific guidance for the prevention and treatment of donor and recipient muscles’ atrophy.　Methods　Seventy adult Sprague Dawley rats were randomly divided into group A (normal); groups B1 and B2 (2w and 4w post-musculocutaneous nerve transection); groups C1 and C2 (2w and 4w post-false-reconstruction of elbow flexion); groups D1 and D2 (2w and 4w post-reconstruction of elbow flexion); There were 7 animal groups, and each group had 10 rats. Muscle wet weights were assessed, muscle fiber cross-sectional area were measured after H&E staining. ε-AChR and γ-AChR mRNA expressions were detected by RT-PCR. ε-AChR and γ-AChR protein expressions were detected by western blot technology.　Results　Compared with rats in group A, rats in group B became limp after musculocutaneous nerve transection, and the foraging movements were restricted, the weight of biceps brachii (recipient muscle) muscle shrunk gradually, the cross-sectional area decreased, the ε-AChR mRNA and protein expressions were downregulated. The γ-AChR expression reappeared later and followed an increasing trend gradually; However, the aboveme ntioned changes were far worse in group C and gradually improved in group D while expression of γ-AChR and ε-AChR in pectoralis major(donor muscle) showed only transient changes.　Conclusions　The transfer of the oblique part of the pectoralis major for elbow flexion reconstruction after musculocutaneous nerve transection can upregulate ε-AChR and downregulate γ-AChR in the recipient muscle and improve the function of elbow flexion in rats.