Guo M
Department of Otorhinolaryngology, Zhujiang Hospital, First Military Medical University, Guangzhou 510282, China.
Zhonghua Er Bi Yan Hou Ke Za Zhi. 2001 Oct;36(5):338-41.
To explore the effects of direct current on vibration of cochlear basilar membrane.
A small hole with a diameter about 0.4 mm, which had the distance of 2.4 mm from round window niche, was made on cochlear basic turn of guinea pig for measuring the velocity of basilar membrane in vivo. On the superior and inferior edge of the measuring window, holes were made on the scala tympani and scala vestibuli for insert stimulating electrode that was made of platinum-iridium. The basilar membrane vibration was elicited by tone and the effect of direct current stimuli were observed by Laser Doppler interference velocimeter.
The velocity of basilar membrane vibration elicited with tone was increased significantly when positive current was delivered to scala vestibuli and the velocity was decreased on the contrary.
The positive endolymphatic potential is essential for cochlea to transit sound to nerve impulse in physiological condition. It is benefit to enhance the gain of cochlear amplifier when the positive potential is increased on the top of outer hair cells, but the extrinsic negative potential should significantly decrease the gain of cochlear amplifier.
探讨直流电对耳蜗基底膜振动的影响。
在豚鼠耳蜗底转距圆窗龛2.4 mm处制作一个直径约0.4 mm的小孔，用于在体测量基底膜速度。在测量窗的上、下边缘，分别在鼓阶和前庭阶打孔，插入由铂铱制成的刺激电极。通过纯音诱发基底膜振动，并用激光多普勒干涉测速仪观察直流电刺激的效果。
当向前庭阶施加正电流时，纯音诱发的基底膜振动速度显著增加，反之则降低。
在生理状态下，内淋巴正电位对于耳蜗将声音转化为神经冲动至关重要。当外毛细胞顶部的正电位增加时，有利于增强耳蜗放大器的增益，但外加负电位应会显著降低耳蜗放大器的增益。
