中文摘要：

目的观察外源性心脏营养素-1（CT-1）对失神经骨骼肌收缩功能的促进作用，并探讨其机制。方法将120只小鼠随机分为12组各10只，制作腓肠肌失神经模型，6个实验组腹腔注射重组小鼠CT-1 100 μg/（kg·d），6个对照组注射等量CT-1溶媒，分别于给药后1、2、4周，检测失神经腓肠肌湿重、横截面积和收缩相关蛋白变化，并于神经修复后4、8、12周，检测神经再支配腓肠肌的复合肌肉动作电位（CMAP）和肌张力。结果与对照组比较，实验组失神经骨骼肌湿重和纤维直径增加，α-肌动蛋白、肌球蛋白重链Ⅱ和Ca^2＋ -ATP酶水平升高，神经再支配骨骼肌的CMAP和肌张力提高。结论外源性CT-1可促进失神经骨骼肌重获神经支配后收缩功能的恢复；其机制为通过提高失神经骨骼肌收缩相关蛋白含量，改善失神经骨骼肌收缩的酶学基础。

英文摘要：

Objective To investigate the effect of exogenous cardiotrophin-1 （CT-1） on contractile ability of denervated muscle. Methods 120 mice were randomly divided into 12 groups, with 10 in each group, whose gastrocnemius muscle was denervated. The treated mouse of 6 groups was injected rmCT-1 intraperitoneally [ 100 μg/（ kg· d） ], and the control mouse of the other 6 groups was injected with corresponding amounts of vehicle. The gastrocnemius muscle was isolated respectively 1,2 and 4 weeks after denervation, and the relevant parameters such as wet weight, cross-sectioned area, and contraction related protein of denervated gastrocnemius muscle were assayed. In addition, the CMAP and tension of reinnervated gastrocnemius muscle were measured 4, 8 and 12 weeks after the transected tibial nerve was repaired. Results Compared with the control group, the wet weight, cross-sectioned area of the treated group increased, the content of α- actin, MHC Ⅱ a and Ca^2＋ATPase in denervated muscle of the treated group increased. The CMAP and tension of reinnerrated muscle increased. Conclusion Exogenous CT-1 can accelerate the functional recovery of denervated muscle after reinnervation by improving contraction related protein and enzymatic basis.