离子通道和机械负荷对耳蜗外毛细胞电致运动的影响

Mechanical responses of cochlear outer hair cells

目的研究豚鼠耳蜗外毛细胞的细胞膜电导和机械负荷对细胞电致运动的动力学特性的影响。方法使用分离自豚鼠耳蜗第四回的外毛细胞,采用全细胞电压钳和微室电极技术。使用以光电二极管为基础的测量系统来测量电致运动。结果外毛细胞的膜电导可以同时影响电致运动的灵敏度和运动的非线性,而机械负载可以显著影响电致运动的幅度、不对称和频率响应。结论外毛细胞的膜电导和机械负荷可以影响外毛细胞的电致运动,从而影响耳蜗放大器功能。

Objective To examine the influence of membrane conductances and mechanical load on the dynamic characteristics of outer hair cell （ OHC） motility.Methods All the experiments were performed on OHCs isolated from the 4th turns of guinea pig cochleae, using whole-cell voltage-clamp and microchamber techniques .Motility was measured using a photodiode-based measurement system.Results Membrane conductances influence both sensitivity and nonlinearity of motility , and that mechanical load significantly affects magnitude , asymmetry and frequency response of motility .Conclusion Membrane conductances and mechanical load influence OHC motility, thereby, the cochlear amplifier .