磁性载mNGF纳米微粒的制备及外磁场引导下修复大鼠坐骨神经损伤的实验研究

摘要

目的 探索外磁场引导下磁性纳米载mNGF微粒修复大鼠坐骨神经损伤的实验效果.方法 以PLGA为包覆材料,制备载Fe3O4和mNGF纳米微粒悬浮液,进行表征.建立大鼠左侧坐骨神经损伤模型分成3组,A、B组每周尾静脉注射1次磁性纳米NGF微粒悬浮液,A组左下肢外磁场引导2 h,B组不施加外磁场;C组每周仅尾静脉注射同含量的NGF溶液.模型建立2个月测定坐骨神经指数(SFI),行左下肢神经电生理检查,测定小腿三头肌湿重比,坐骨神经切片HE染色观察.实验数据进行统计学分析.结果 A组的SFI、神经传导速度、肌肉湿重比均高于B组和C组,差异具有统计学意义(P<0.05),B组与C组的SFI、神经传导速度、肌肉湿重比的差异无统计学意义(P>0.05).组织学观察可见A组的再生神经的排列及密度均好于B组和C组.结论 外磁场引导下磁性纳米载NGF微粒能够促进大鼠坐骨神经损伤的修复.%Objective To investigate the experimental effectofmagnetic mNGF nanoparticlesguided by out-side magnetic on the the sciatic nerve injury.Tianjin 300211,China.Methods As a drug carrier,PLGA connects magneticironparticles with and mNGF. The nanoparticle suspension liquid was prepared and its physicochemical properties was characterized. The model of the left sciatic nerve injury in rats was divided into 3 groups. Rats in Group A received intravenous tail vein injectionof magnetic mNGF nanoparticlesfollowed by two-hour outside mag-neticguidance once week.Group B received intravenous tail vein injection of magnetic mNGF nanoparticles without outside magnetic guidance once week. Group C received intravenous tail vein injection of the same content mNGF once week. Two months later,we measured the ischial nerve index(SFI)and madenerve electrical physiological ex-amination under anesthesia.We also measured quality ratio of triceps surae and did left sciatic nerve slice HE stain-ing.Finally,experimental data were statistically analyzed. Results The SFI,nerve conduction velocity and quality ratio of triceps surae of Group A were higher than those of Group B and Group B(P<0.05).There was no significant difference between Group B and Group C(P>0.05).The arrangement and density of the regeneration nerve in Group A were better than those of Group B and C under optical microscope. Conclusion The results showed that the magnetic mNGF nanoparticles guided by outside magnetic can promote the recovery of rat sciatic nerve injury.