大鼠耳蜗疆孔内听神经纤维的定量观察

Quantitative Analysis of Auditory Nerve Fibers in Habenula Perforata in Rat

目的探讨定量观察正常SD大鼠疆孔内听神经纤维数量的方法。方法取5只正常SD大鼠耳蜗(正常组),EPON812包埋后,沿蜗轴平面作半薄切片,甲苯胺蓝染色后光镜下观察拍照,用Adobe Photoshop图像处理软件处理图像,并采用计数单个完整疆孔内神经纤维数量均值及疆孔内神经纤维密度均值的方法分别对耳蜗底回起始段、底回末段及中回中段疆孔内的听神经纤维进行计数,对耳蜗各部位听神经纤维数目的差异进行方差分析。以同法对5只乌苯苷耳中毒SD大鼠(耳中毒组)疆孔内听神经进行了定量观察,以验证此法的实用性。结果正常SD大鼠疆孔内的神经纤维数量在耳蜗底回起始段、耳蜗底回末段、耳蜗中回中段分别为22.78±7.15、130.12±50.73、58.66±9.12根,各部位的差异有显著统计学意义(F=195.15,P<0.01);疆孔内听神经纤维密度(104根/mm2)在底回起始段、底回末段、中回中段分别为7.17±1.51、23.95±2.73、15.95±2.26,在底回末段的疆孔内神经纤维的数量多于耳蜗底回起始端和耳蜗中回中段(F=804.86,P<0.01)。耳中毒组耳蜗底回起始段、末段和耳蜗中回中段疆孔内神经纤维数量分别为13.63±12.34、80.69±24.42、54.94±8.79根,神经纤维密度(104根/mm2)分别为2.06±1.53、15.94±2.26、15.68±2.52,其中,耳蜗底回起始段和末段均明显少于相应的正常组(P<0.01)。结论采用疆孔内神经纤维密度均值定量观察疆孔内听神经纤维的数量,其结果可靠且更稳定。

Objective To examine the number of nerve fibers in the cochlear habenula perforata in normal rat.Methods 5 normal SD rats were sacrificed,prepared for semi-thin cochlear sections.The sections were stained with toluidine blue and photographed under light microscope.The number of nerve fibers per habenula perforata,and the density of auditory nerve fibers in habenula perforata were counted at different locations,such as the region of hook,the upper region of basal turn,and the region of second turn.The differences of auditory nerve fibers at various locations were statistically analyzed by analysis of variance（ANOVA）.Results The number of nerve fibers per habenula perforata at different locations of normal SD rats were 22.78±7.15,130.12±50.73 and 58.66±9.12,respectively;the density of auditory nerve fibers was 7.17±1.51,23.95±2.73 and 15.95±2.26 accordingly.The population of auditory nerve fibers in the upper region of basal turn was much higher than hat in the bottom of basal turn and the second turn.The quantification of auditory nerve density in habenula peforate was more effective and credible than the counting of auditory nerve numbers per habenula peforate.Conclusion The density of nerve fibers in the habenula perforata was a credible and stable parameter for observing the auditory nerve injury in the cochlea.