CODING IN AUDITORY NEURONS--EFFECTS OF AMINO ACIDS

描述：过去几年在本实验室完成的研究 多年来，我们对两个密切相关的问题有了进一步的了解 在听觉研究中：1)抑制性氨基酸是如何在 已知的用于编码声音信息的脑干听觉回路？2)什么 衰老对脑内抑制性氨基酸神经传递的影响 听觉脑干？这种性质的研究已经取得了重大进展。 老年性耳聋的性质，这是一种老年人的主要疾病，可能会导致 涉及老年性听力损失的药物治疗策略。 耳蜗核(CN)和耳蜗核的体内离子导入和体外研究 下丘(IC)发现抑制性氨基酸 神经递质在动态范围的控制中起着关键作用， 噪声中信号的回波抑制和检测。最近的这方面的研究 实验室表明，CN和IC内的电路经历了与年龄相关的 与抑制性神经传递相关的变化。目前的提案 将通过开展以下工作来扩展这一坚实的工作基础 建议的研究：1)微离子导入，以检查 抑制性氨基酸GABA在调幅反应中的作用 IC中的正弦；2)神经化学技术进一步表征 GABAA受体分子性质的年龄相关变化；和3) 单单位生理学检查与年龄相关的反应变化 DCN梭形细胞的特性。

DESCRIPTION: Studies completed in this laboratory during the past several years have contributed to our understanding of two closely related questions in auditory research: 1) How do inhibitory amino acids function within known brainstem auditory circuits to encode acoustic information? 2) What is the impact of aging on inhibitory amino acid neurotransmission in the auditory brainstem? Studies of this nature have made significant inroads into the nature of presbycusis, a major disorder among the aged and may lead to pharmacological treatment strategies for age-related hearing loss. In vivo iontophoretic and in vitro studies in cochlear nucleus (CN) and inferior colliculus (IC) have revealed that inhibitory amino acid neurotransmitters are critically involved in the control of dynamic range, echo suppression and detection of signal in noise. Recent studies from this laboratory suggest that circuits within the CN and IC undergo age-related changes associated with inhibitory neurotransmission. The current proposal will extend this strong foundation of work by carrying out the following proposed studies: 1) microiontophoresis to examine the role of the inhibitory amino acid GABA in shaping responses to amplitude modulated sinusoids in the IC; 2) neurochemical techniques to further characterize age-related changes in the molecular nature of the GABAA receptor; and 3) single unit physiology to examine age-related changes in the response properties of DCN fusiform cells.