创伤性脊髓损伤是残疾的主要原因,目前尚无完全有效的治疗方法。最近使用硬膜外电刺激的研究表明,在运动康复方面取得了重大进展,即使在疾病的慢性阶段使用。本研究旨在探讨硬膜外电刺激对脊髓损伤大鼠运动恢复的影响。此外,我们旨在阐明运动恢复的神经生理机制.首先,我们对冲击脊髓损伤模型进行了改进,导致严重和永久性的运动缺陷,持续2个月。接下来,我们开发并测试了一种用于大鼠的植入式硬膜外脊髓刺激器装置,该装置包含电极和植入式发生器。最后,评价硬膜外电刺激对Wistar大鼠脊髓损伤后运动恢复的影响。将60只动物分为以下几组:(i)硬膜外电刺激严重损伤(损伤+神经刺激,n=15),(ii)无刺激的严重伤害(组伤害,n=15),(iii)无电池假植入(假,n=15),和(Iv)对照组,没有手术干预(对照,n=15)。所有动物都使用Basso进行每周评估,Beattie,布雷斯纳汉(BBB)运动评定量表指数,斜面,和OpenField测试在病变前一周开始并持续八周。在这段时间之后,处死动物,移植其脊髓并准备进行组织学分析(苏木精-伊红)和NeuN的免疫组织化学,β-III-微管蛋白,突触素,和Caspase3.最后,NeuN阳性神经元核通过体视学定量;β-微管蛋白的荧光信号强度,突触素,和胱天蛋白酶3使用落射荧光显微镜定量。第5周后,损伤+刺激组BBB评分较损伤组显著改善(p<0.05)。体视学分析显示,与损伤组相比,损伤刺激组的神经细胞平均计数明显更高(1783±2vs.897±3,p<0.001)。此外,突触素的荧光信号强度在损伤+刺激组中明显高于损伤组(1294±46vs.1198±23,p<0.01);β-III-微管蛋白信号强度无统计学差异。最后,与损伤组(1225±87p<0.05)相比,刺激组的Caspase3信号强度(727±123)明显降低,在假手术组和对照组中观察到接近水平。我们的数据表明,硬膜外电刺激对遭受冲击诱发的创伤性脊髓损伤的大鼠具有再生和保护作用。
Traumatic spinal cord injury is a major cause of disability for which there are currently no fully effective treatments. Recent studies using epidural electrical stimulation have shown significant advances in motor rehabilitation, even when applied during chronic phases of the disease. The present study aimed to investigate the effectiveness of epidural electric stimulation in the motor recovery of rats with spinal cord injury. Furthermore, we aimed to elucidate the neurophysiological mechanisms underlying motor recovery. First, we improved upon the impact spinal cord injury model to cause severe and permanent motor deficits lasting up to 2 months. Next, we developed and tested an implantable epidural spinal cord stimulator device for rats containing an electrode and an implantable generator. Finally, we evaluated the efficacy of epidural electrical stimulation on motor recovery after spinal cord injury in Wistar rats. A total of 60 animals were divided into the following groups: (i) severe injury with epidural electrical stimulation (injury + stim, n = 15), (ii) severe injury without stimulation (group injury, n = 15), (iii) sham implantation without battery (sham, n = 15), and (iv) a control group, without surgical intervention (control, n = 15). All animals underwent weekly evaluations using the Basso, Beattie, Bresnahan (BBB) locomotor rating scale index, inclined plane, and OpenField test starting one week before the lesion and continuing for eight weeks. After this period, the animals were sacrificed and their spinal cords were explanted and prepared for histological analysis (hematoxylin-eosin) and immunohistochemistry for NeuN, β-III-tubulin, synaptophysin, and Caspase 3. Finally, NeuN-positive neuronal nuclei were quantified through stereology; fluorescence signal intensities for β-tubulin, synaptophyin, and Caspase 3 were quantified using an epifluorescence microscope. The injury + stim group showed significant improvement on the BBB scale compared with the injured group after the 5th week (p < 0.05). Stereological analysis showed a significantly higher average count of neural cells in the injury + stim group in relation to the injury group (1783 ± 2 vs. 897 ± 3, p < 0.001). Additionally, fluorescence signal intensity for synaptophysin was significantly higher in the injury + stim group in relation to the injury group (1294 ± 46 vs. 1198 ± 23, p < 0.01); no statistically significant difference was found in β-III-tubulin signal intensity. Finally, Caspase 3 signal intensity was significantly lower in the stim group (727 ± 123) compared with the injury group (1225 ± 87 p < 0.05), approaching levels observed in the sham and control groups. Our data suggest a regenerative and protective effect of epidural electrical stimulation in rats subjected to impact-induced traumatic spinal cord injury.