大鼠FK506套管模型与自体神经移植模型脊髓背角c-fos表达的比较研究

Comparative study of c-fos expression in spinal dorsal horn between autogeneic nerve graft model and PDLLA/FK506 tube model of rats

目的建立大鼠外消旋聚乳酸/FK506(PDLLA/FK506)复合套管模型和大鼠外周神经自体神经移植神经再生模型,观察对比各模型神经恢复过程中机械痛觉超敏的变化及脊髓背角c-fos表达的改变,探讨两种神经再生模型中神经再生与神经性疼痛的联系。方法雄性Wistar大鼠60只随机分成3组,每组20只。A组为自体神经移植再生模型组;B组为PDLLA/FK506套管修复模型组;C组假手术组。分别制成模型,术后24d起检测机械刺激阈值,术后27d起计数c-fos阳性细胞。结果 A、B组各项指标与C组比较有显著差异(P<0.05);A组与B组比较c-fos表达阳性细胞计数及机械痛阈无显著差异。结论两种模型再生神经生长进入去神经支配区域时,均出现支配区域的痛觉超敏和疼痛相关行为,神经性疼痛程度无差异。

Objective To establish a rat model of poly-dl-lactide（PDLLA）/FK506 composite tube and a rat model of autogeneic nerve graft,to observe the changes of mechanical allodynia and c-fos expression during nerve recovery process,and to explore the relationship between nerve regeneration and neuropathic pain in these two models.Methods 60 male Wistar rats were randomly divided into three groups：group A（autogeneic sciatic nerve graft,n=20）,group B（PDLLA/FK506 repairing tube,n=20）and group C（sham operation,n=20）.Animals were made into different models,and then the threshold of mechanical stimulation was measured from 24 d after operation and the number of cells positively expressing c-fos was counted from 27 d after operation.Results Compared with group C,the threshold of mechanical stimulation and the number of cells positively expressing c-fos were significantly different in group A or group B（P0.05）.No significantly differences were found yet in the above two indexes between group A and group B.Conclusion Once the injured fibers of sciatic nerve in both PDLLA/FK506 model and autograft model regenerate into denervated dermatomic areas,the allodynia and pain-related behaviors in innervated areas will occur although the grade of neuropathic pain has no difference.