爆震后豚鼠耳蜗螺旋神经节细胞超微结构改变及其中睫状神经营养因子的表达

A study of ultrastructural changes and expression of ciliary neurotrophic factor in cochlear spiral ganglion cells in guinea pigs after blast exposure

目的探讨爆震后豚鼠耳蜗听阈明显升高时螺旋神经节细胞超微结构改变及其中睫状神经营养因子表达的变化。方法复制爆震致聋豚鼠模型,不同时段测ABR阈值,取耳蜗做病理,观察耳蜗螺旋神经节细胞数量和超微结构的变化；用免疫组化检测耳蜗螺旋神经节细胞内CNTF的表达。结果爆震组21d的耳蜗螺旋神经节细胞在二下组为(25．00±7．16)个,而正常对照组为(52．00±5．32)个。以上数据组间统计学差异有显著意义。豚鼠螺旋神经节细胞透射电镜观察见爆震组震后3d出现线粒体明显肿胀,线粒体嵴断裂；21d后线粒体数量明显减少,且有畸形；经爆震声暴露后21d的豚鼠耳蜗中轴切片上CNTF阳性反应细胞数量减少,而且染色分布不均匀。结论爆震对耳蜗螺旋神经节细胞的数量和超微结构均有明显影响,同时在早期干扰螺旋神经节细胞内CNTF的表达。

Objective To study the uhrastructural changes and expression of ciliary neurotrophic factor in cochlear spiral ganglion cells in guinea pigs after blast exposure. Methods The pathologic and ultrastructural changes of cochlear spiral ganglion cells in guinea pigs were observed 3 days and 21 days after blast exposure. The expression of ciliary neurotrophic factor in cochlear spiral ganglion cells was detected using immunohistochemical analysis after blast exposure. Results The number of spiral ganglion cells in the twolow part of cochlea were 25.00 ±7.16 in the blast group and 52.00 ± 5.32 in the normal group 21 days after blast exposure. Obvious swollen mitochondria was observed 3 days after blast exposure and abnormal mitochondrion was observed 21 days after blast exposure. The expression of CNTF in cochlear spiral ganglion cells was reduced and abnormal after blast exposure. Conclusions Blast exposure had obvious influence on the uhrastructure and quantity of cochlear spiral ganglion cells. The expression of CNTF in cochlear spiral ganglion cells was reduced and abnormal.