噪声对豚鼠耳蜗外淋巴谷氨酸含量及耳蜗电位的影响  

Effect of Noise on Concentration of Glutamate in Perilymph and Cochlear Potential of Guinea Pig Cochlear

作　　者：孙勍[1] 李兴启[1] 张国庆[2] 单希征[3] 刘军[1] 

机构地区：[1]解放军总医院耳鼻咽喉-头颈外科研究所,北京100853 [2]解放军总医院实验仪器测试中心 [3]武警总医院耳鼻咽喉-头颈外科

出　　处：《听力学及言语疾病杂志》2004年第2期93-95,共3页Journal of Audiology and Speech Pathology

基　　金：国家自然科学基金资助项目(编号 3 9870 797)

摘　　要：目的　观察噪声暴露对豚鼠耳蜗外淋巴液中谷氨酸含量及耳蜗电位的影响。方法　应用高效液相色谱仪检测豚鼠噪声暴露耳与对照耳耳蜗外淋巴液中谷氨酸的含量 ,同时记录噪声暴露前及噪声暴露 2小时的耳蜗电位 (CM、CAP)。结果　对照耳外淋巴液中谷氨酸含量为 4 .2 7± 0 .4 0 μmol/L ,噪声暴露耳为 8.15± 0 .78μmol/L ,提示噪声暴露 2小时后外淋巴液中谷氨酸含量明显增加 (P <0 .0 5 ) ;CM相对幅度下降 ,并且其非线性特点消失 ,CAP阈值平均升高了约 5 0dB。结论　噪声暴露可以使豚鼠耳蜗外淋巴液中的谷氨酸含量明显增加 ,并引起耳蜗功能的改变。提示噪声不仅损伤外毛细胞 ,还可以使内毛细胞谷氨酸过度释放产生兴奋性毒性 ,直接引起内毛细胞及耳蜗传入神经的损伤。Objective To observe the effect of noise on the concentration of glutamate in perilymph and cochlear potential of guinea pig cochlear.Methods Glutamate in perilymph of both noise group and non-noise group was determined by high performance liquid chromatography. The CM and CAP were recorded before and 2 hours after noise exposure.Results After noise exposure the concentration of glutamate in perilymph was significantly elevated( P <0.05). The average concentration of glutamate in the noise group was 8.15±0.78 μmol/L, while in the non-noise group, it was 4.27±0.40 μmol/L. The amplitude of CM was declined,and the I/O function of CM lose its nonlinear characteristic. The average CAP threshold was elevated about 50 dB SPL.Conclusion The glutamate in the perilymph of the cochlear can be significantly elevated after noise exposure, and cause a series of changes of cochlear function. Our results suggest that glutamate might be over released from the inner hair cells after noise exposure, which induced its ototoxic effect in turn.

关 键 词：外淋巴液 谷氨酸 高效液相色谱法 耳蜗电位 噪声 含量 

分 类 号：R764.433[医药卫生—耳鼻咽喉科]