CYTOCHEMISTRY OF CENTRAL AUDITORY PATHWAYS

中枢听觉通路的细胞化学

• 批准号: 2125956
• 负责人: RICHARD L SAINT MARIE
• 金额: $ 19.34万
• 依托单位: HOUSE RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-09-01 至 1997-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2125956
• 关键词: aspartate; auditory nuclei; auditory pathways; binaural hearing; cats; chinchilla; gamma aminobutyrate; glutamates; glycine; immunochemistry; inferior colliculus; neural information processing; neuroanatomy; neurochemistry; neuronal transport; neuropharmacology; neurotransmitter transport

The long term goal of this project is to understand the structural and neurochemical circuitry of the auditory brainstem in sufficient detail that we can make intelligent structure/function correlations and predict how each part contributes to auditory signal processing. In the present proposal, we will concentrate on the nuclei of the lateral lemniscus (NLL). The NLL provide both monaural and binaural inputs to the auditory midbrain, i.e., the central nucleus of the inferior colliculus (ICc). They are the second largest source of inputs to the ICc (surpassed only by projections from the cochlear nucleus) and are its single largest source of inhibitory inputs. Emerging evidence suggests that inhibition may have many roles in shaping the responses of ICc neurons, including frequency tuning, temporal response patterns, and rate-intensity functions. Inhibition from the dorsal nucleus of the NLL has been implicated in binaural suppression in the ICc. In addition to their main projections to the ICc, the NLL also contribute extralemniscal projections to the auditory thalamus and superior colliculus, and descending projections to the cochlear nucleus and superior olivary complex. Yet, of all regions of the central auditory system, the NLL are the least understood in terms of their cellular composition and cellular connectivity. In the present proposal, we will characterize the cellular architecture of the NLL and correlate these findings with cellular differences in transmitter type and synaptic target. We will also examine the afferent inputs to the crossed and uncrossed projections of the dorsal nucleus of the NLL, so that we can infer something about the types of information being carried to the ICc by each component of its projections. These experiments are designed to bridge the gap between purely morphological and purely neurochemical studies by examining the cytochemistry of morphologically defined neurons in the NLL. In addition, by examining the afferent and efferent connections of these morphologically and cytochemically defined neurons, we hope to learn something about the types of information that each transmits to its synaptic targets. This should better enable us to relate our observations to neurophysiological and neuropharmacological investigations, and to predict how each component of the NLL projections contributes to monaural and binaural signal processing.

该项目的长期目标是了解结构和 听觉脑干的神经化学电路足够详细 我们可以建立智能结构/功能相关性并预测 每个部分如何促进听觉信号处理。现在 提案，我们将专注于外侧Lemniscus的核 （nll）。 NLL为听觉提供单声道和双耳输入 中脑，即下丘的中央核（ICC）。他们 是ICC的第二大投入来源（仅超过 来自耳蜗核的预测），是其最大的来源 抑制输入。新兴的证据表明抑制可能有 在塑造ICC神经元的反应中的许多作用，包括频率 调整，时间响应模式和速率强度函数。 NLL背侧核的抑制已与 ICC中的双耳抑制。除了他们的主要预测 ICC，NLL还为 听觉丘脑和上级丘陵，以及下降的预测 耳蜗核和上橄榄络合物。但是，在所有地区 中央听觉系统，NLL是最不理解的 它们的细胞组成和细胞连通性。现在 提案，我们将表征NLL和 将这些发现与发射机类型的细胞差异相关联 突触目标。我们还将检查交叉的传入输入 和NLL背侧核的未透明的投影，以便我们可以 推断出有关将信息类型的类型推论到ICC的 其预测的每个组成部分。这些实验被设计为 桥梁纯粹形态学和纯神经化学之间的缝隙 通过检查形态定义的神经元的细胞化学研究 在NLL中。另外，通过检查传入和传入 这些形态学和细胞化学定义的神经元的连接， 我们希望能学到有关每个信息类型的信息 传输到其突触目标。这应该更好地使我们联系 我们对神经生理和神经药物的观察 调查，并预测NLL预测的每个组成部分 有助于单膜和双耳信号处理。