Curation and management of electrophysiological data obtained form outer hair cells isolated from Cavia Porcellus

从豚鼠外毛细胞中获得的电生理数据的整理和管理

• 批准号: 9111391
• 负责人: Brenda Frances Farrell
• 金额: $ 4.42万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-04-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9111391
• 关键词: Accounting; Acetylcholine; Adult; Aging; Ally; Amplifiers; Animals; Behavior; Biomedical Engineering; Biophysics; Cavia; Cavia porcellus; Cell Shape; Cell Signaling Process; Cell membrane; Cells; Charge; Chemicals; Chloride Ion; Chlorides; Chlorpromazine; Cholesterol; Cholinergic Agents; Cochlea; Data; Development; Endolymph; Environment; Exhibits; Failure; Frequencies; Genes; Goals; Hair Cells; Health; Hearing; Individual; Labyrinth; Lateral; Length; Liquid substance; Location; Measures; Mechanics; Membrane; Membrane Lipids; Membrane Potentials; Membrane Proteins; Modeling; Molecular; Motor; Movement; Neurosciences; Neurotransmitters; Organ; Outer Hair Cells; Output; Passive Ion Transport; Performance; Pharmaceutical Preparations; Phase; Physics; Physiological; Production; Property; Rest; Role; Salicylic Acids; Sexual Maturation; Staging; Structure; System; Techniques; Therapeutic Intervention; base; deafness; density; design; electrical potential; electrical property; improved; in vivo; male; model development; patch clamp; pressure; rat Pres protein; receptor; response; sound; theories; voltage; voltage clamp

DESCRIPTION (provided by applicant): There are differences in electrical potential and chemical composition between the fluids of the inner ear and the insides of its cells. These electrochemical gradients are the battery providing power to a membrane-based motor essential for hearing. Systematic differences in the strength of the battery predict gradients in motor function within the inner ear. Recent findings have confirmed that the functional density decreases on going from high to low frequency regions of the inner ear and suggest gradients in motor function along the length of individual outer hair cells. We will investigate both the organ and cellular level gradients to achieve our goal of characterizing the mechanisms that maintain motor function and cochlear amplification at optimal performance. The membrane protein prestin is an integral part of the motor and its presence results in currents that are out of phase with the AC voltage that evokes them. Membrane voltage changes have similar effects on prestin-associated currents and outer hair cell length changes. The voltage of maximum gain for both the currents and length changes should be maintained close to the in vivo resting potential to assure that outer hair cell receptor potentials generate maximal electromechanical forces. A variety of external manipulations modify the voltage of maximum gain of both functions. Some modifiers act on the membrane directly; these include changes in holding potential, tension, and cholesterol as well as a variety of membrane reactive drugs such as salicylate and chlorpromazine. Changes of chloride ion concentration and the neurotransmitter acetylcholine also modify motor performance. Aim 1 will determine whether there is a tonotopic gradient in the voltage of maximum gain by recording from cells isolated from all cochlear turns. Aim 2 will measure the gradients in prestin-function along the length of individual outer hair cells and determine the contribution of the non-homogeneous motor distribution to the fine structure of whole cell currents. An aspiration pipette will mechanically deform the membrane at different locations along the lateral wall and the resulting charge movement will be measured with a whole-cell patch pipette. Aim 3 will examine interactions between modifiers and compare the data to predictions of a systems based model of the outer hair cell. Aims 1&2 will reveal how the outer hair cell membrane potential is established under physiologic conditions and clarify the differences in prestin function between the high and low frequency regions of the inner ear. Data from all three aims will be used to clarify the role of prestin's transporter properties in the motr mechanism. Cell biophysics, neuroscience, chemical physics, and bioengineering approaches will be used. The studies will contribute to improved therapeutic interventions for the hearing impaired particularly loss resulting from decreased output or failure of the cochlear battery. The impact, if any, of maturation and sex on prestin-function will also be identified.

描述（由申请人提供）：内耳液体和其细胞内部之间的电位和化学成分存在差异。这些电化学梯度是电池，为听力所必需的膜基马达提供动力。电池强度的系统性差异预测了内耳内运动功能的梯度。最近的研究结果已经证实，功能密度从内耳的高频区域到低频区域降低，并且表明运动功能沿着单个外毛细胞的长度存在梯度。我们将研究器官和细胞水平的梯度，以实现我们的目标，即表征维持运动功能和耳蜗放大的机制。膜蛋白普雷斯廷是马达的一个组成部分，它的存在导致电流的相位不同 用交流电压唤起它们膜电压变化对prestin相关电流和外毛细胞长度变化有类似的影响。电流和长度变化的最大增益电压应保持接近体内静息电位，以确保外毛细胞受体电位产生最大的机电力。各种外部操纵修改两个功能的最大增益的电压。一些修饰剂直接作用于膜，包括保持电位、张力和胆固醇的变化，以及各种膜反应药物，如水杨酸盐和氯丙嗪。氯离子浓度和神经递质乙酰胆碱的变化也会改变运动表现。目标1将通过记录从所有耳蜗匝分离的细胞来确定最大增益电压中是否存在音调分布梯度。目标2将测量沿着单个外毛细胞长度的Prestin函数梯度，并确定非均匀运动分布对全细胞电流精细结构的贡献。抽吸移液管将使膜在沿侧壁的沿着不同位置处机械变形，并且将用全细胞贴片移液管测量所得电荷移动。目标3将检查修改器之间的相互作用，并将数据与基于系统的外毛细胞模型的预测进行比较。目的1和2将揭示外毛细胞膜电位是如何在生理条件下建立的，并阐明普雷斯廷在内耳高频区和低频区之间的功能差异。所有三个目标的数据将被用来澄清的作用，普雷斯廷的转运蛋白的性质在motr机制。将使用细胞生物物理学，神经科学，化学物理学和生物工程方法。这些研究将有助于改善对听力受损者的治疗干预措施，特别是因耳蜗电池输出减少或故障而造成的听力损失。还将确定成熟和性别对prestin功能的影响（如果有的话）。