失神经支配肌肉感觉神经营养活性的研究

背景研究已证实骨骼肌有神经营养活性,但对失神经支配条件下骨骼肌内感觉神经营养因子变化情况及其感觉神经营养活性状况研究较少.目的探讨失神经支配红、白肌肉内神经生长因子(NGF)变化规律及 NGF含量与感觉神经营养活性之间的关系.设计非随机对照实验研究.地点和对象华中科技大学同济医学院动物中心提供Wister大白鼠 40只,体质量 200～ 250g,雌雄不限.干预将实验组大鼠双侧下肢坐骨神经切断,制成肌肉失神经支配模型.主要观察指标运用肌肉免疫组织化学染色方法检测 NGF含量,用鸡胚背根神经节培养方法测定肌肉提取液感觉神经营养活性.结果腓肠肌和比目鱼肌失神经支配后其NGF含量均下降,两种肌肉组内比较无统计学意义,组间比较以比目鱼肌组下降明显;但两种失神经支配肌肉提取液感觉神经营养活性却未降低,在伤后7天时反高于正常值,两种肌肉组间比较无差异.结论周围神经损伤会引起其相应支配靶器官-肌肉组织内NGF的含量发生变化,且具有时间性,红、白肌肉内 NGF含量的变化不一致;失神经支配肌肉的神经营养活性是各种营养因子的共同作用结果,不能用单一某种神经营养因子来代表.

Study on the sense neurotrophism of denervated muscles

BACKGROUND:It was proved that there was neurotrophism in the muscles, but there was no more knowledge on the neurotrophic factors and the neurotrophism of the denervated muscles. OBJECTIVE:To clarify the character of nerve growth factor(NGF) in the denervated red and white muscles and the relationship between the amount of NGF and sensitive neurotrophism of denervated red and white muscles. DESIGN: Non-randomized control trial. SETTING and PARTICIPANTS:Forty Wister rats,weighing 200-250g were provided by the Animal Center of the Tongji Medical College in the Huazhong University of Science and Technology. INTERVENTION:The model of the denervated gastrocnemius and soleus was made by clipping the sciatic nerve . MAIN OUTCOME MEASURE:The immunohistochermistry was taken to measure the amount of NGF in muscles ,and the neurotrophism of extracts of muscles was tested with culture of dorsal root ganglions at the time of the lst, 3rd, 7th and 14th day after injury. RESULTS: The amount of NGF in denervated gastrocnemius(GAS) and soleus(SOL) decreased, especially in SOL. The neurotrophism of the extracts of the two kinds of denervated muscles promoted in the 1st week. CONCLUSION:The peripheral nervous injury causes changes of NGF level of their innervated muscle in a time-dependent manner and there exists difference between changes of NGF in white and red muscles.Yet,the neurotrophic activity of the denervated muscle results from not only NGF, but also the integration of multiple neurotrophic factors.