神经生长因子和电刺激对去神经大鼠腓肠肌组织结构和肌纤维类型的影响

Effects of Nerve Growth Factor and Electricity Stimulus on Configuration and Fibre Type of Gastrocnemius of Denervated Rats

目的探讨神经生长因子(NGF)和低频电刺激对去神经骨骼肌的形态结构和骨骼肌类型转变的影响。方法以去神经大鼠为模型,分别对模型大鼠的腓肠肌注射NGF,施加频率为2Hz的电刺激30d,采用免疫组织化学法、图像分析法观测肌肉形态结构的变化情况和肌肉类型的转变情况,分析两者各自的作用。结果去神经组肌纤维排列混乱,细胞间界限不明显;去神经注射NGF组和去神经电刺激组肌纤维排列较去神经组整齐,细胞间界限较明显,细胞核数目较正常组多。与正常组比较,其他各组Ⅰ型肌纤维所占比例增加(P<0.05),Ⅱ型肌纤维所占比例下降(P<0.05);去神经注射NGF组、去神经电刺激组和去神经组两种类型肌纤维比较差异无显著性意义(P>0.05)。结论注射NGF和施加低频电刺激能使去神经骨骼肌形态结构趋向好转。

Objective To explore the effects of nerve growth factor （NGF） and low frequency electricity stimulus on the configurations of skeletal muscle cells and the change of muscle fibre types in the denervated skeletal muscle separately. Methods The denervated rat model was established and model animals were injected with the NGF and given the stimulus （frequency=2 Hz） about 30 days. The configurations and the change of muscle fibre types were observed by immunohistochemistry and image analysis. Results The muscle fibre was in chaos and the boundary was not obvious among cells in the denervated rats; the muscle fibre of the denervated rats with NGF injection and low frequency electricity stimulus was more regular and the boundary of cells was clearer, the cells number was more than those of the denervated rats. Compared to normal rats, the proportion of I muscle fibre in the denervated rats increased （ P〈0.05）, whereas the proportion of Ⅱ muscle fibre decreased （ P〈0.05） ; it had no significant differences of the two types of muscle fibre between the denervated rats with NGF injection, low frequency electricity stimulus and the denervated rats （ P〈0.05）. Conclusion NGF injection and low frequency electricity stimulus can make the configurations of denervated muscle to better.