摘要
目的:建立大鼠自体神经移植模型,观察大鼠神经恢复过程中行为学改变和机械痛觉过敏的变化以及脊髓背角c-fos表达的改变,探讨外周神经损伤再生与痛觉过敏的关系。方法:雄性Wistar大鼠40只,体重180～200g,分成两组每组20只,A组为自体神经移植组,B组为假手术组。术后18d起检测行为学、机械刺激阈值和热缩足反射时间及c-fos表达计数。结果:A组术后24d后机械痛阈和热缩足反射潜伏期与B组相比差异有统计学意义。A组术侧L4～5脊髓背角与B组相比较,背角浅层c-fos计数增多,差异有统计学意义。A组39d和27dc-fos表达差异无统计学意义,机械痛阈与热缩足反射潜伏期39d与21d差异有统计学意义。结论:自体神经移植模型再生神经生长进入去神经支配区域后,触觉诱发疼痛和脊髓背角浅层c-fos表达,同时出现再生神经支配区域的机械痛觉过敏和疼痛相关行为。
Objective To investigate whether an autograft injury in rats could alter the behavioral response to tactile stimuli and whether this was associated with a change in the pattern of c-fos expression in the dorsal horn. Methods 40 male wistar rats were randomly divided into sham-operation group （group B） and autograft group （group A）. The rats in group A underwent autograft. The right sciatic nerve was exposed but not crushed under the standard anaesthetic regimen in group B. The wound was sutured in all animals. The process of regeneration of peripheral nerve and neuropathic pain were evaluated at 18 to 39 days following operation. Mechanic withdrawal threshold and thermal withdrawal latency were assessed by von-fray filaments and Hargreaves method repectively 18,21,24,27,30,33,36,39 d after operation. Five rats of each group were given innoxious touch-stimulus for 2 hours before killed 21,27,33,39 d after operation. The spinal cord was obtained after death. Immunohistochemistry was employed to investigate the expression of c-fos. Results The hyperalgesia appeared on the 24th day after injury-operation of the sciatic nerve and reached its maximal level on the 27th day after operation. The threshold was severely decreased on the 27th day, which correlated with the time point of recovery of sensory function for all rats and remained low for 2 weeks, then gradually increased. On 39th day, the threshold was still significantly different as compared to the sham-operated animals. Paralleled with hyperalgesia, the expression of c-fos elicited by touch-stimulus increased significantly and it mainly distributed at middle of superficial layer in laminal Ⅰ - Ⅱ in spinal dorsal horn in A group by touch-stimulus. The expression of c-fos did not significantly decrease between 27th and 39th day in group A（P 〉 0.05） and there had a significant difference in c-fos expression between the two groups. The mechanic withdrawal threshold and thermal withdrawal latency significantly decreased between 27th and 39th day in
出处
《实用医学杂志》
CAS
2008年第19期3296-3298,共3页
The Journal of Practical Medicine
基金
湖北省卫生厅科研基金资助项目(编号:JX2B45)
