脑源性神经营养因子对面神经损伤的修复作用

Brain-derived neurotrophic factor in the regeneration of facial nerve

目的探讨局部应用脑源性神经营养因子(BDNF)对面神经损伤的修复作用。方法将成年新西兰兔面神经上颊支切除5mm,在断端间置入硅胶再生室,随机实验组室内注入BDNF,对照组用生理盐水。术后4周和8周进行电生理学、组织病理学观察和形态学定量分析。结果术后4周,两组电刺激面神经很少能引发面肌兴奋,有髓轴索计数,轴索直径和面积t检验,两组差异有显著性意义(P<0.05)。术后8周面神经复合肌动作电位(CMAP)BDNF组运动神经传导速度(MCV)明显短于对照组,有髓轴索计数,轴索直径和面积BDNF组大于对照组(P<0.05)。结论局部应用BDNF可促进面神经损伤的修复。

Objective To study the role of BDNF in generation of facial nerve.Methods Twenty Adult New Zealand rabbits' bilateral super buccals of facial nerves were transected and connected with silicone tube(ST).Randomly,BDNF was injected in one side of ST and normal saline in another one.4,8 weeks after the operation,both BDNF group and SAL group underwent electrophysiology test and histopathology as well as quantity analysis.Results Four weeks later,both BDNF and SAL group failed in eliciting muscular excitement by stimulating facial nerve;T test showed significant difference between the two groups(P< 0.05)about the average of myelinated axons, the axon cross sectional areas and the diameter of axons.8 weeks later motor nerve conduction velocity of facial muscular excitement was (38.6±4.5) m/s in BDNF group and (30.4±6.6) m/s in SAL group.The average number of myelinated axonsaxon cross sectional areas and diameter of axons were 2084±574, 2.24±0.23, 3.31±0.54 in BDNF group and 1247±492, 1.83±0.36, 2.52±0.67 in control one,respectively.T test showed significant difference between both of them(P< 0.05).Conclusion BDNF enhance facial nerve regeneration in Adult New Zealand rabbits.