Wang Xue-Song, Chen Xue, Gu Tian-Wen, Wang Ya-Xian, Mi Da-Guo, Hu Wen
Department of Orthopedics, The Affiliated Hospital of Jiangnan University (The Third People's Hospital of Wuxi City), Wuxi, Jiangsu Province, China.
Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu Province, China.
Neural Regen Res. 2019 Dec;14(12):2164-2172. doi: 10.4103/1673-5374.262595.
Quantitative assessment of the recovery of nerve function, especially sensory and autonomic nerve function, remains a challenge in the field of nerve regeneration research. We previously found that neural control of vasomotor activity could be potentially harnessed to evaluate nerve function. In the present study, five different models of left sciatic nerve injury in rats were established: nerve crush injury, nerve transection/suturing, nerve defect/autografting, nerve defect/conduit repair, and nerve defect/non-regeneration. Laser Doppler perfusion imaging was used to analyze blood perfusion of the hind feet. The toe pinch test and walking track analysis were used to assess sensory and motor functions of the rat hind limb, respectively. Transmission electron microscopy was used to observe the density of unmyelinated axons in the injured sciatic nerve. Our results showed that axonotmesis-evoked vasodilatation in the foot 6 months after nerve injury/repair recovered to normal levels in the nerve crush injury group and partially in the other three repair groups; whereas the nerve defect/non-regeneration group exhibited no recovery in vasodilatation. Furthermore, the recovery index of axonotmesis-evoked vasodilatation was positively correlated with toe pinch reflex scores and the density of unmyelinated nerve fibers in the regenerated nerve. As C-fiber afferents are predominantly responsible for dilatation of the superficial vasculature in the glabrous skin in rats, the present findings indicate that axonotmesis-evoked vasodilatation can be used as a novel way to assess C-afferent function recovery after peripheral nerve injury. This study was approved by the Ethics Committee for Laboratory Animals of Nantong University of China (approval No. 20130410-006) on April 10, 2013.
在神经再生研究领域，对神经功能恢复进行定量评估，尤其是感觉和自主神经功能的评估，仍然是一项挑战。我们之前发现，可以利用血管舒缩活动的神经控制来评估神经功能。在本研究中，建立了五种不同的大鼠左侧坐骨神经损伤模型：神经挤压伤、神经横断/缝合、神经缺损/自体移植、神经缺损/导管修复和神经缺损/无再生。使用激光多普勒灌注成像分析后足的血流灌注。分别使用夹趾试验和行走轨迹分析评估大鼠后肢的感觉和运动功能。采用透射电子显微镜观察损伤坐骨神经中无髓轴突的密度。我们的结果表明，神经损伤/修复后6个月，轴突断裂引起的足部血管舒张在神经挤压伤组恢复到正常水平，在其他三个修复组部分恢复；而神经缺损/无再生组的血管舒张未恢复。此外，轴突断裂引起的血管舒张恢复指数与夹趾反射评分和再生神经中无髓神经纤维的密度呈正相关。由于C纤维传入神经主要负责大鼠无毛皮肤浅表血管的舒张，目前的研究结果表明，轴突断裂引起的血管舒张可作为评估周围神经损伤后C传入神经功能恢复的一种新方法。本研究于2013年4月10日获得中国南通大学实验动物伦理委员会批准（批准号：20130410-006）。
