脊髓损伤后14天大鼠运动功能、NT-3和TrkC表达的变化及不同电针的影响

Changes of motor function, Nt-3 and Trkc expression in rats at 14 day post-spinal cord injury and the effect of different electroacupuncture

为了研究不同电针对脊髓损伤(SCI)大鼠(Rattus norvegicus)脊髓内神经营养因子3(NT-3)及其酪氨酸激酶受体C(Trk C)表达的影响,探讨NT-3,Trk C在实验性脊髓损伤发病及修复过程中的作用机制及不同电针干预对其的影响.将雄性清洁级SD大鼠随机分为空白、模型、脉冲电针及音乐电针4个组别,每组12只,采用改良式的Allen’s打击法复制模型.两组电针组选取"大椎"、"命门"进行不同电针干预,1次/日,20 min/次,空白组及模型组在治疗组治疗时进行抓取束缚,保证处理条件的相同.SCI后14天,通过BBB(Basso-Beattic-Bresnahan)评分评价大鼠后肢运动功能的变化,采用HE染色、尼氏染色观察大鼠受损脊髓病理改变及神经元情况,Western blot检测NT-3,Trk C在大鼠受损脊髓表达的情况.BBB结果显示,经脉冲电针与音乐电针治疗后,脊髓损伤大鼠后肢运动功能较模型组均有改善(P<0.01),且音乐电针评分高于脉冲电针,但两组比较无统计学差异;HE染色与尼氏染色结果示,经14天脉冲电针与音乐电针治疗脊髓损伤大鼠神经元形态均可得到恢复,且音乐电针优于脉冲电针;Western blot结果显示,损伤脊髓大鼠中NT-3,Trk C经脉冲与音乐电针治疗后较模型组均有显著升高(P<0.01),且音乐电针对NT-3,Trk C表达的影响高于脉冲电针,但两组比较无统计学差异.脉冲电针与音乐电针均能诱导SCI大鼠脊髓内NT-3及Trk C表达,促进脊髓损伤后神经再生修复功能,且音乐电针较脉冲电针作用略胜一筹.

This paper aims to investigate the influence on the expression of neurotrophin 3（NT-3） and tyrosine kinase receptor C（Trk C） in the 14 th day post-spinal cord injury（SCI） rats which have had different electro-acupuncture（EA） treatment, and to elucidate the possible role of NT-3 and Trk C in the development of experimental SCI and the effect of different EA for them. Adult male sprague-dawley（SD） rats were randomly divided into normal control group（n=12）, SCI model group（SCI-induction without treatment, n=12）, pulsed EA group（SCI-induction with pulse-EA treatment, n=12）, and music EA group（SCI-induction with music-EA treatment, n=12）. SCI model was established by using the modified Allen＇s method. Basso-Beattic-Bresnahan（BBB） scale was performed to assess the locomotor function of rats. HE staining and Nissl＇s staining were used to observe the pathological changes of SCI Rats and the situation of remnant neuron. The expression of NT-3 and Trk C was detected by using Western blot. The BBB score of SCI model group was significantly lower than that of normal control group, while pulsed-EA group and music-EA group could reverse it in the 14 th day post-SCI（P〈0.01）, while there was no statistical difference between the two treatment group（P〈0.05）. The results of HE staining and Nissl＇s staining showed that the two kinds of treatment could improve this pathological changes. The expression of NT-3 and Trk C in SCI model group decreased significantly in the 14 th day post-SCI（P〈0.01）, the two kinds of treatment could improve this pathological change, they could up-regulate the level of expression of NT-3 and Trk C（P〈0.01）, but there was no statistical difference between the two treatment group（P〈0.05）. The levels of NT-3 and Trk C in SCI rats were lower than normal. The pulse- and music-EA treatments may effectively induce the levels of NT-3 and Trk C in the spinal cord, then promote the recovery of hindlimb function of SCI rats; and the effectiveness of music-EA offered a good trend in recovery than that of pulse-EA treatment, but there was no statistical difference between the two treatment group in locomotor function and the expression of NT-3 and Trk C in the 14 th day post-SCI rats.