IN VIVO ANALYSIS OF OUTER HAIR CELL MOTILITY

在过去的十年中，OHC的许多运动特征 通过体外(分离细胞)方法获得，包括电压 依赖性、亚细胞位置、非线性度、灵敏度和相位。 尽管取得了这样的进展，但准确地设想仍是一项艰巨的任务 OHC运动如何在基底膜(BM)引起尖锐的调谐， IHC和单个单元。完全可能的是， 在体外观察到的OHC运动可能不同于正常范围内的运动 在活体环境中。必要时体内特性的测定 为了准确评估OHC运动性对BM的影响 机械师。为外周贡献一些特别的东西的动力 听觉处理，但到底是什么以及如何仍然是关键问题 当然需要活体研究。在这方面，它建议 目的：分析完整耳蜗内OHC运动的特点。 1)有没有可能测量电刺激的影响 单个OHC对基底膜概念的运动性？活体内 在单个OHC中的电流注入期间测量BM运动可以 明确证明OHC可以影响BH，并且可能允许 体内电压-运动(V-M)功能的测定。 2)体内OHC非线性电容的电压依赖性是什么？ OHC具有与电压相关的电容。非线性的度量 电容将提供对OHC的电压依赖性的洞察 体内的运动性，并应补充体内的V-M功能的数据。 3)短暂性低氧是否改变了体内的电压依赖性 动力性和非线性电容函数？很明显，新陈代谢 在体内的侮辱可以戏剧性地和可逆地干扰正常 科尔蒂器官的功能。这些OHC中伴随的变化 这些特征可能为OHC的运动参与提供证据。 4)OHC是否通过缝隙连接连接到支持呼叫？一个敏感的人 将使用电容技术来确认兹维洛基ET的结果 等，这表明耦合的存在。它们之间的交流 细胞类型可能为控制OHC提供一种有趣的机制 功能。 总之，这种活体分析可能有助于理解OHC是如何 履行其职责，并进一步提供对听觉的洞察 以HC功能障碍为基础的病理学。

During the last decade, many characteristics of OHC motility have been garnered through the in vitro (isolated cell) approach, including voltage dependence, subcellular site, nonlinearity, sensitivity, and phase. Despite such progress, it remains a difficult task to envision exactly how OHC motility might induce sharp tuning in the basilar membrane (BM), IHCs and single units. It is entirely possible that characteristics of OHC motility observed in vitro may differ from those within the normal in vivo milieu. A determination of in vivo characteristics in requisite for an accurate assessment of the influence of OHC motility on BM mechanics. OHC motility in contributing something special to peripheral auditory processing, but exactly what and how remain key questions which certainly require in vivo investigations. In this regard, it in proposed to analyze aspects of OHC motility in the intact cochlea. 1) Is it possible to measure the effects of the electrically evoked motility of a single OHC on basilar membrane notion? The in vivo measurement of BM motion during current injection in a single OHC may unequivocally demonstrate that OHC can influence the BH, and may permit the determination of the in vivo voltage-to-movement (V-M) function. 2) What in the voltage dependence of OHC nonlinear capacitance in vivo? OHCs possess a voltage dependent capacitance. Measures of nonlinear capacitance will provide insight into the voltage dependence of OHC motility in vivo, and should compliment data on the in vivo V-M function. 3) Does transient hypoxia alter the voltage dependence of the in vivo motility and nonlinear capacitance functions? It is clear that metabolic insult in vivo can dramatically and reversibly interfere with the normal functioning of the organ of Corti. A concomitant change in these OHC characteristics may provide evidence for OHC motility involvement. 4) Are OHCs coupled via gap junctions to supporting calls? A sensitive capacitive technique will be used to confirm the results of Zwislocki et al., which indicate that coupling exists. Communication between these cell types may provide an interesting mechanism for controlling OHC function. In sum, this type of in vivo analysis may help to understand how the OHC performs its duties, and further, may provide insight into the auditory pathologies which have as their basis OHC dysfunction.