双靶区神经环路磁刺激调控大鼠星形胶质细胞改善脊髓损伤运动功能的研究

关键词：脊髓损伤  神经环路磁刺激  星形胶质细胞  胶质瘢痕

Keywords:spinal cord injury  neural circuit magnetic stimulation  astrocyte  glial scar

摘要：

      摘要 目的：观察脊髓损伤后早期应用神经环路磁刺激治疗对星形胶质细胞活化的作用，探讨双靶区神经环路磁刺激促进脊髓损伤康复的作用机制。 方法：将36只成年雄性SD大鼠随机分成3组，Sham+SS组：假手术+假刺激组，SCI+SS组：SCI+假刺激组，SCI+NC-MS组：SCI+神经环路磁刺激组，每组12只。建立脊髓损伤大鼠模型，术后第3天SCI+NC-MS组接受真刺激，另外两组接受假刺激，每日1次，每周5次，共3周。分别在术前、术后1d、3d、7d、14d、21d采用BBB评分、斜板试验评价运动功能；治疗结束后处死大鼠并提取损伤区脊髓，HE染色观察各组损伤区脊髓的病理变化；Western Blot测定各组脊髓中胶质纤维源性酸性蛋白（GFAP）的表达。 结果：①行为学：BBB评分和斜板试验显示SCI+NC-MS组术后7d、14d、21d的运动功能显著优于SCI+SS组（P<0.001）；②HE染色显示，相对于SCI+SS组，SCI+NC-MS组的脊髓结构改善，病变程度相对减轻；③Western Blot显示，和SCI+SS组相比，SCI+NC-MS组的GFAP蛋白表达量明显降低（P<0.05）。 结论：双靶区神经环路磁刺激的早期应用可以抑制星形胶质细胞活化，减少脊髓损伤区胶质瘢痕形成，促进运动功能康复。

Abstract:

      Abstract Objective：To observe the effect of neural circuit magnetic stimulation on the activation of astrocytes in the early stage after spinal cord injury，and to explore the mechanism of neural circuit magnetic stimulation on promoting the rehabilitation of spinal cord injury. Method：Thirty-six adult male SD rats were randomly divided into three groups： Group Sham+SS is the sham operation+sham stimulation， group SCI+SS is the spinal cord injury model+sham stimulation， group SCI+NC-MS is the spinal cord injury model+ neural circuit magnetic stimulation. Every group had 12 rats. The model of spinal cord injury was established successfully. Group SCI+NC-MS was treated with the true magnetic stimulation on the 3rd day post-surgery， while the other two groups received sham stimulation once a day， five times a week for three weeks. The assessment of motor function was tested by BBB scale and Inclined plane test at different time points(1d before modeling and 1d、3d、7d、14d、21d after the surgery). Injured spinal cord tissue was harvested after finishing the treatment. HE staining was used to observe the pathological changes of spinal cord. Furthermore，the expression of glial fibrillary acidic protein (GFAP) in the spinal cord was determined by Western Blot. Result：①Locomotion assessment： BBB scores and Inclined plane test in the group SCI+NC-MS were greatly better than that of the group SCI+SS from 7d to 21d (P<0.001). ②HE staining showed that compared with the group SCI+SS， the structure of the spinal cord in the group SCI+NC-MS was improved and the degree of injury was relatively mild. ③Western Blot showed that the activation of astrocytes in the group SCI+NC-MS was significantly lower than that in the group SCI+SS(P<0.05). Conclusion：The early application of neural circuit magnetic stimulation can effectively restrain the activation of astrocytes， suppress the formation of glial scar， thus promoting the rehabilitation of motor function.