EFFERENT INNERVATION OF IDENTIFIED VESTIBULAR AFFERENTS

已识别的前庭传入的传出神经支配

• 批准号: 6043360
• 负责人: ANNA LYSAKOWSKI
• 金额: $ 15.95万
• 依托单位: UNIVERSITY OF ILLINOIS AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-08-01 至 2000-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6043360
• 关键词: afferent nerve; brain stem; calretinin; chinchilla; efferent nerve; immunocytochemistry; immunoelectron microscopy; innervation; muscarinic receptor; neuroanatomy; neuronal transport; vestibular apparatus

The purpose of this grant is to investigate the efferent innervation of the peripheral vestibular apparatus. Knowledge of the chemical composition and projections of the efferent neurons in the brainstem to the peripheral labyrinth may help to understand the role of the vestibular efferent system in health and disease. Recent work has suggested that the neurons in the efferent nucleus may be heterogeneous in their transmitter neurochemistry and in their peripheral targets. This suggestion of heterogeneity, if confirmed, would change our long-held view that the vestibular efferents are a nonspecific system. The goal of this study is to define subpopulations of efferent neurons in the chinchilla based on their brain stem locations, their projections to one, the other or both ears, their neurochemical identities and their peripheral endings on hair cells, calyces and other afferent processes. Specific aims are: l) to characterize anatomical and neurochemical subpopulations of efferent neurons in the brainstem efferent neurons using retrograde tracers and transmitter immunohistochemistry, and 2) to relate the central subpopulations of vestibular efferent neurons to their terminations in the periphery. Efferent neurons in the brainstem will be identified by means of retrograde tracer injections into the peripheral vestibular apparatus and will be simultaneously characterized immunohistochemically by the use of antibodies to several putative neurotransmitters (acetylcholine, calcitonin gene-related peptide, nitric oxide synthase, met-enkephalin and others). The analysis will be extended to the periphery where electron microscopic immunohistochemical methods will be used to characterize neurochemically distinctive efferent boutons according to their terminations in the sensory epithelium, that is, by the class of afferents (calyx, dimorphic or bouton) or region (central or peripheral) that they innervate. Vestibular afferents will be identified by means of extracellular HRP injections, calretinin immunohistochemistry, or other means. The distribution of muscarinic receptor subtypes will also be examined in an attempt to understand the slow response of afferents to stimulation of the efferents. The significance of this project is that a precise knowledge of the various elements comprising the population of efferent neurons, and their targets in the periphery, will further our understanding of brain stem control of peripheral sensory processing. It is hoped that as a result of this work, it will no longer be sufficient merely to define subgroups in the brain stem without establishing their relationship to the periphery. Nor will it be sufficient to illustrate peripheral terminations without stating their specific location within the endorgan. The intent is to produce a body of knowledge about the structural basis of the efferents from which physiologically and pharmacologically testable hypotheses can be derived.

这笔赠款的目的是研究 外围前庭设备。化学成分的知识 和外围神经元中传出神经元的预测 迷宫可能有助于了解前庭效果的作用 健康与疾病的系统。最近的工作表明神经元 在发射器中，传出核可能是异质的 神经化学及其周围靶标。这个建议 如果确认，异质性将改变我们长期以来的观点 前庭传出是一个非特异性系统。这项研究的目的是 基于 他们的脑干位置，对一个或两个的预测 耳朵，神经化学身份和头发上的周围结尾 细胞，钙和其他传入过程。具体目的是：l） 表征出现的解剖学和神经化学亚群 使用逆行示踪剂和 发射机免疫组织化学和2） 前庭传出神经元的亚群终止 周边。脑干中的传出神经元将通过手段识别 逆行示踪剂注射到周围前庭设备 并将通过使用同时以免疫组织化学来表征 对几种推定神经递质的抗体（乙酰胆碱， 降钙素基因相关的肽，一氧化氮合酶，met-脑链蛋白和 其他的）。分析将扩展到电子的外围 微观免疫组织化学方法将用于表征 神经化学上独特的传出胸子根据他们的 感官上皮的终止，即传入类别 （花萼，二态或Bouton）或区域（中央或外围） 支配。前庭传入将通过 细胞外HRP注射，钙网蛋白免疫组织化学或其他 方法。毒蕈碱受体亚型的分布也将是 进行了检查，以了解传入的缓慢反应 刺激传出。该项目的重要性是 包括包括人口的各种元素的精确知识 传出的神经元及其在周围的目标将进一步 了解脑干控制周围感觉处理。它 希望由于这项工作，它将不再足够 仅仅是为了定义脑干中的亚组 与外围的关系。不足以说明 外围终止，而没有说明其特定位置 内尔根。目的是产生有关 从生理和 可以得出可以得出药理学测试的假设。