【摘要】 目的:局部应用血管内皮生长因子(vascular endothelial growth factor,VEGF)蛋白可加速神经再生,促进其功能恢复。探讨局部注射pHVEGF165质粒对周围神经再生的作用。方法:实验于2004-03/06在武汉协和医院手外科实验室完成。实验动物:成年雄性Wistar大鼠45只。实验分组:随机分成3组,每组15只。即对照组、pHVEGF165质粒25μg和50μg组。实验方法:①制备pHVEGF165质粒。②制成双侧坐骨神经损伤动物模型,于神经断端间及周围肌肉内对照组局部注射生理盐水,pHVEGF165质粒25μg组和50μg组局部分别注射pHVEGF16525μg,50μg。实验评估:①术后4,6和8周行腓肠肌湿重检测与组织形态学观察。②术后6,8周行神经断面图象分析,测量有髓纤维密度、平均轴突直径、髓鞘厚度与有髓纤维总数。③术后8周通过电生理检测记录复合肌肉动作电位波幅,潜伏期,计算出运动神经传导速度。统计分析以上数据比较各组大鼠坐骨神经再生情况。结果:45只大鼠全部进入结果分析。①坐骨神经组织学检查结果:术后4周,各组大鼠神经均以大量变性的髓鞘为主;6,8周时,对照组神经断面仍可见到一些变性神经纤维,再生之神经纤维数量少,pHVEGF165质粒组的再生神经纤维数量增多也更加成熟,且pHVEGF165质粒50μg组再生神经纤维已接近正常神经组织。②腓肠肌湿重:神经损伤6周及8周,pHVEGF165质粒50μg组均明显优于对照组、pHVEGF165质粒25μg组[6周:(733.64±41.69),(491.82±40.21),(680.08±48.70)mg,8周:(906.68±35.03),(577.26±57.22),(772.74±61.14)mg,P<0.05]。③坐骨神经图象分析:6周和8周,pHVEGF165质粒25μg组、50μg组明显优于对照组(P<0.05),pHVEGF165质粒50μg组最优(P<0.05)。④电生理检测结果:术后8周,pHVEGF165质粒50μg组运动神经传导速度、复合肌肉动作电位波幅及潜伏期指标显示明显优于pHVEGF165质粒25μg组和对照组(P<0.05),pHVEGF165质粒25μg组居中。结论:局部注射phVEGF165质粒治疗周围神经损伤具有可行性,可促进神经轴突再生,加速神经功能恢复。并且这种作用可能存在剂量依赖性。更多还原

【Abstract】 AIM: Local vascular endothelial growth factor (VEGF) injection could accelerate nerve regeneration, and improve nerve functional recovery. In this paper, the effect of local pHVEGF165 injection on peripheral nerve regeneration was investigated. METHODS: The experiment was performed in the laboratory of Department of Hand Surgery of Wuhan Union Hospital from March to June of 2004. Forty-five adult male Wistar rats were selected and randomly divided into control group, 25 μg and 50 μg pHVEGF165 groups with 15 animals in each group. ① pHVEGF165 plasmid was prepared. ② The neurotomy to bilateral sciatic nerve was carried out to establish models. The injured segments were administrated by local injection of normal saline, and 25 μg and 50 μg pHVEGF165 groups by local injection of 25 μg and 50 μg pHVEGF165, respectively. At 4, 6, and 8 weeks after operation, wet weight of gastrocnemius muscles was detected and histomorphological observation was conducted. Nerve sectional image analysis was carried out 6 and 8 weeks after operation to measure the density of myelinated fiber, mean diameter of neuraxis, thickness of myelin sheath and total number of myelinated fiber; at 8 weeks after operation, the amplitude and latency of compound muscle action potential were recorded by eletrophysiological detection to count the nerve conduction. The sciatic nerve regeneration was compared by above data. RESULTS: Forty-five rats were involved in the result analysis. ① Four weeks after operation, a large amount of degenerated myelin sheath was found in rat sciatic nerves of each group. At the 6th and 8th weeks, some degenerated nerve fibers still remained in the nerve section of the control group, and only small amount of regenerated nerve fibers was observed. The regenerated nerve fibers of pHVEGF165 groups were much more in both quantity and maturity; furthermore, the fibers of 50 μg pHVEGF165 group were much closer to normal nerve tissue in appearance and amount. ② Six and eight weeks after nerve injury, the wet weight of gastrocnemius muscles of 50 μg pHVEGF165 group was significantly superior to that of the control group, and 25 μg pHVEGF165 group [6 weeks: (733.64±41.69), (491.82±40.21), (680.08±48.70) mg; 8 weeks: (906.68±35.03), (577.26±57.22), (772.74±61.14) mg, P < 0.05]. ③ Image analysis showed that the 25 and 50 μg pHVEGF165 groups were superior than the control group at 6 and 8 weeks (P < 0.05), and 50 μg pHVEGF165 group was the best (P < 0.05). ④ Eletrophysiological detection suggested that 8 weeks after operation, the nerve conduction and amplitude and latency of compound muscle action potential of the 50 μg pHVEGF165 group were better than those of the 25 μg pHVEGF165 group and control group (P < 0.05), and 25 μg pHVEGF165 group was the middle one. CONCLUSION: Local pHVEGF165 injection could facilitate peripheral nerve regeneration and promote the functional recovery in a dose-dependent manner.更多还原