局部缺血对面神经损伤后雪旺细胞增殖的影响

The Impact of Ischemic on the Proliferation of Schwann Cells after Facial Nerve Injury

目的探讨局部缺血对面神经损伤后雪旺细胞增殖的影响,为临床治疗颅底骨折伴发面神经损伤提供新的思路。方法75只SD雄性大鼠,分为对照组(30只)、实验组(30只)及空白组(15只)。对照组给予左侧面神经单纯压榨性损伤;实验组给予左侧面神经相同的压榨性损伤后,显微镜下剥除神经外膜周围血管;空白组为假手术组。其中25只于术后3 d、7 d和21 d进行行为学观察及电生理检测,另外50只于术后3 d、5 d和7 d采集面神经标本,S-100抗体标记雪旺细胞,行免疫组化染色分析。结果电生理检测及行为学分析显示:空白组无面瘫表现,实验组与对照组均出现面瘫表现。随着时间延长,两组面瘫症状均有恢复,但实验组恢复速度明显缓慢;免疫组化显示:术后3 d、5 d和7 d空白组雪旺细胞改变无明显差异。术后3 d实验组及对照组雪旺细胞均开始增殖,术后5 d两组达到增殖高峰,术后7 d实验组雪旺细胞开始明显减少,对照组无明显改变。结论与单纯面神经损伤比较,损伤伴缺血可明显导致损伤处雪旺细胞的增殖减少,阻碍面神经的修复。

Objective To observe the proliferation of Schwann cells after facial nerve injury associated with ischemia and to find the new insight for the clinical treatment of skull base fractures with facial nerve injury. Methods Seventy-five male SD rats were divided into 3 groups： control group （n=30）, experimental group （n=30） and blank group （n=lS）. Left facial nerve trunks were selected in 3 groups. The control group accepted crush injury only; the experimental group accepted crush injury and stripped of blood vessels around epineurium under microscope; the blank group served as sham group. Twenty-five rats received behavioral observation and electrophysiological testing 3, 7 and 21 days after the operation; The remaining 50 rats were killed 3, 5 and 7 days after operation respectively, the obtained specimens were stained by S-100, and observed by immunohistochemical staining analysis. Results Electrophysiological testing and behavioral analysis showed no facial paralysis performance in blank group; The experimental and control group showed facial paralysis performance, and with the prolongation of time the two groups have a recovery performance. However, the recovery rate of the experimental group was significantly slower. Immunohistochemistry showed the Schwann ceils had no significant change among 3, 5 and 7 days after operation in blank group; The Schwann cells of the experimental and control group began to proliferate 3 days the operation, the two groups reached the peak of proliferation 5 days the operation; The Schwann cells significantly reduced in experimental group 7 days the operation, while no significant change was observed in control group. Conclusion Crush associated with ischemia could reduce the proliferation of Schwann cells and hinder the recovery of facial nerve.