Neural Plasticity in the Adult Gustatory System

成人味觉系统的神经可塑性

• 批准号: 7082165
• 负责人: DAVID L HILL
• 金额: $ 33.53万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-01 至 2009-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7082165
• 关键词: chorda tympani; denervation; dietary sodium; electron microscopy; electrophysiology; furosemide; histology; immunocytochemistry; innervation; laboratory rat; low salt diet; nerve injury; neural plasticity; neuromuscular function; neurophysiology; neuropsychology; taste; taste buds; tongue; trigeminal nerve

DESCRIPTION (provided by applicant): The dependence of taste buds on innervation has been used as a model to understand nerve/tar interactions. Loss of innervation results in a loss of the normal morphological appearance of taste buds, while restoration of innervation results in a recovery of taste bud morphology and function. The adult regenerating gustatory system is especially susceptible to environmental manipulations. Combining unilateral chorda tympani nerve section and low sodium diet in adult rats results in a variety of functional and anatomical alterations in both taste buds and in the regenerating nerve. Furthermore, functional and anatomical alterations also occur in the intact, contralateral side of the tongue. In addition to injury-induced effects related to the peripheral portion of the chorda tympani nerve, there are also extreme morphological changes that involve the central portion of the sectioned nerve. Coordinated studies will take advantage of the remarkable functional and anatomical plasticity induced by combined unilateral chorda tympani nerve section and dietary sodium restriction. A systems-level approach will focus on neural plasticity in the adult rat gustatory system. Combined anatomical, neurophysiological, electron microscopic, and immunocytochemical techniques will permit a determination of: 1) the stability of innervation of single taste buds over time in normal adults and determine the accuracy of chorda tympani neurons in reinnervating their original targets; 2) the extent and nature of terminal field plasticity in the NTS; 3) the extent and nature of synaptic plasticity in the NTS; and 4) the functional consequences of unilateral chorda tympani nerve section and/or dietary sodium restriction on taste responses in the NTS. Findings from these studies will address the broader topics of sensory coding, the role of neural activity in maintenance of sensory function, and the temporal stability and accuracy of peripheral innervation under normal circumstances and in response to nerve damage. Results will also enable a clearer understanding of the neurobiological sequelae of human taste nerve damage sustained pathologically, or during middle ear or oral surgery.

描述（由申请人提供）：味蕾对神经的依赖性已用作了解神经/焦油相互作用的模型。神经支配的丧失导致味蕾正常形态外观的丧失，而神经支配的恢复导致味蕾的形态和功能的恢复。成人再生味道系统特别容易受到环境操作的影响。在成年大鼠中结合单侧丘巴尼神经剖面和低钠饮食会导致味蕾和再生神经的各种功能和解剖学改变。此外，功能性和解剖学改变也发生在舌头的完整，对侧。除了损伤引起的作用与Chorda鼓神经的周围部分相关的作用外，还存在极端的形态变化，涉及截面神经的中心部分。协调的研究将利用单侧鼓膜神经部分和饮食钠限制引起的显着功能性和解剖学可塑性。系统级方法将集中于成年大鼠味道系统中的神经可塑性。结合解剖学，神经生理学，电子显微镜和免疫细胞化学技术将允许确定：1）正常成年人中单个味蕾的神经支配的稳定性，并确定Chorda Tympani神经元在重新启动其原始靶标方面的准确性； 2）NTS中末端场可塑性的程度和性质； 3）NTS突触可塑性的程度和性质； 4）单方面丘巴尼神经部分的功能后果和/或饮食中对NTS味觉反应的限制。这些研究的发现将介绍更广泛的感觉编码的主题，神经活动在维持感官功能中的作用以及在正常情况下的时间稳定性和外周神经的准确性以及对神经损伤的响应。结果还将使人们能够更清楚地了解人类味道神经损伤的神经生物学后遗症，或者在中耳或口腔手术期间受到的持续性。