脑溢安对大鼠舌下神经压榨伤后神经营养因子受体P75表达的影响

Effect of Nao yi-an on the expression of P75 in rats with hypoglossal nerve injury

目的:观察大鼠舌下神经压榨损伤后舌下神经核内P75的表达及中药脑溢安对其表达的影响。方法:建立大鼠舌下神经压榨损伤模型,脑溢安治疗组用脑溢安颗粒剂以灭菌生理盐水调成药液灌胃,正常对照组和实验对照组用灭菌生理盐水灌胃。动物分别存活1、4、7、14 d后灌注固定并取脑切片,采用免疫组织化学方法观察舌下神经核内运动神经元胞体P75的表达变化。结果:正常组大鼠两侧舌下神经核内均无P75免疫反应阳性物表达,生理盐水对照组和脑溢安治疗组损伤侧(右侧)舌下神经核内神经元胞体开始表达P75。2组均术后1 d低量表达P75,7 d P75表达量达高峰;生理盐水对照组14 d P75表达量仍维持高水平,略有下降;脑溢安治疗组14 d P75表达量开始下降,7 d和14 d P75表达有显著性差异(P<0.05)。与生理盐水对照组相比,脑溢安治疗组损伤后4、7 d和14 d损伤侧舌下神经核内P75免疫阳性细胞平均灰度值显著降低,阳性细胞数减少,有统计学差异(P<0.05)。结论:脑溢安下调大鼠舌下神经压榨损伤后神经元胞体P75的表达。

Objective：To detect the expression of P75 following hypoglossal nerve injury in rats and effect of Nao yi-an on P75 expression.Methods：Sixty healthy adult SD rats were used.Twenty SD rats were selected randomly as normal control（NC）,the rest were crushed on the right hypoglossal nerve and divided randomly into two groups：one group（n=20） were intragastrically given NYA（NYA treatment group）,and the other group（n=20）,as well as the NC group,were treated with normal saline（surgery control group,SC group） in the same way.The rats were allowed to survive for 1,4,7 and 14 days respectively after operation and perfused transcardially with proper fixatives.Frozen sections were processed for immunohistochemstry（IHC） to decide the P75 neurotrophin receptor（P75） expression level in the motoneurons of hypoglossal nucleus.Results：The expression of P75 was not observed in SC group but was detectable in all animals.This expression of P75 was observed 1 d after the injury,the earliest time point in this study,peaked at 7 d and remained until 14 d after the operation.However,P75 immunoreactivity in the hypoglossal motoneurons in NYA group was lower than NS control group at 4,7,14 d（P〈0.05） after injury.Conclusion：NYA can down-regulate the P75 expression in the motoneurons of hypoglossal nucleus after hypoglossal nerve injury.