EFFERENT INNERVATION OF THE VESTIBULAR APPARATUS

这笔小额赠款将用于收集有关传出神经的初步数据。 周围前庭器官的神经支配。 最近的工作已经 这表明，这个群体可能是异质的， 神经递质神经化学及其外周靶点。 这 如果得到证实，这一建议将改变我们的观点，即传出神经是 非特定系统。 这项研究的目的是确定潜在的 根据它们的传出神经元的亚群， 脑干位置，它们对一只耳朵、另一只耳朵或两只耳朵的投射， 它们的神经化学特性和它们在毛发上的末梢 细胞、肾盏和其他传入突起。 具体目标是：1） 来定义脑干中不同的传出神经元群 基于目前对可能的递质和传出解剖结构的了解， 2）将这些知识与区域分析相关联 化学定义的传出终扣和纤维的突触关系 外围。 脑干中的传出神经元将通过 将荧光逆行示踪剂注射到外周的方法 前庭器官，并将同时表征 通过使用针对几种假定的 神经递质（乙酰胆碱、γ-氨基丁酸、降钙素 基因相关肽、甲硫氨酸脑啡肽等）。 分析将 延伸到周围， 方法将用于表征神经化学上独特的 感觉终末的传出终末 上皮 这个项目的意义在于， 知识的不同元素组成的人口 传出神经将进一步加深我们对脑干控制的理解， 周边感觉加工

This Small Grant will be used to gather preliminary data on the efferent innervation of the peripheral vestibular apparatus. Recent work has suggested that this population may be heterogeneous in its neurotransmitter neurochemistry and in its peripheral targets. This suggestion, if confirmed, would change our view that the efferents are a nonspecific system. The goal of this study is to define potential 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 terminations on hair cells, calyces and other afferent processes. The specific aims are: 1) to define separate populations of efferent neurons in the brain stem based on current knowledge of possible transmitters and efferent anatomy and 2) to correlate this knowledge with an analysis of the regional synaptic relations of chemically-defined efferent boutons and fibers in the periphery. Efferent neurons in the brain stem will be identified by means of fluorescent retrograde tracer injections into the peripheral vestibular apparatus and will be simultaneously characterized immunohistochemically by the use of antibodies to several putative neurotransmitters (acetylcholine, gamma-aminobutyric acid, calcitonin gene-related peptide, 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 in terms of their terminations in the sensory epithelium. The significance of this project is that a precise knowledge of the different elements comprising the population of efferents will further our understanding of brain stem control of peripheral sensory processing.