GLOMERULI AS FUNCTIONAL UNITS FOR OLFACTORY CODING

肾小球作为嗅觉编码的功能单位

• 批准号: 6760943
• 负责人: JOHN G HILDEBRAND
• 金额: $ 32.72万
• 依托单位: UNIVERSITY OF ARIZONA
• 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 2005-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6760943
• 关键词: Manduca; brain mapping; chemoreceptors; computational neuroscience; confocal scanning microscopy; electrophysiology; histochemistry /cytochemistry; mathematical model; neural information processing; odors; olfactions; olfactory lobe; olfactory stimulus; pheromone; sensory discrimination; sensory mechanism; sensory signal detection; voltage /patch clamp

DESCRIPTION (adapted from applicant's abstract): The primary olfactory centers in the brains of diverse animals, including humans, are characterized by an array of synaptic modules called glomeruli. These centers are thought to be organized chemotopically, such that odor information is represented spatially among glomeruli, but this important hypothesis has not been tested comprehensively in a species offering the advantages of anatomical simplicity, identifiable glomeruli, accessible receptor cells and central neurons, and chemically identified, behaviorally relevant odors. Moreover, despite dramatic advances in chemosensory research, we still do not understand how complex odor stimuli are encoded in neural activity, within and among glomeruli, that ultimately leads to appropriate behavioral responses. This project builds on a firm foundation of technical experience and knowledge about an experimentally favorable model, the olfactory system of Manduca sexta, which is comparable to its vertebrate counterpart in organization and function and permits the hypothesis of glomerular chemotopy to be tested with greater precision than has been possible in other species. This model system also offers an exceptional opportunity to unravel the synaptic neural circuitry within and between identified glomeruli in order to reveal how specific odor information is processed at its first way-station in the brain. By means of intracellular recording and staining, extracellular multichannel recording, laser-scanning confocal and transmission electron microscopy, and computer-assisted mathematical modeling, we will focus on identified glomeruli in recognizable clusters to: (1) test the hypothesis that glomeruli are organized chemotopically by determining what chemical, temporal, and intensity properties of behaviorally significant odor stimuli are analyzed and encoded by individual neurons innervating particular glomeruli; (2) characterize synaptic circuits within and between glomeruli to learn how the various types of neurons associated with glomeruli interact to shape the signas conveyed by output neurons projecting to higher centers in the brain; and (3) develop mathematical models of characterized neurons to generate testable hypotheses about their physiology and synaptic interactions. This research will promote understanding of basic olfactory mechanisms in all animals, including mankind, and promises to contribute toward explanation of sensory disorders such as parosmia, hyposmia, and anosmia.

描述（改编自申请人的摘要）：主要嗅觉中心 在包括人类在内的多种动物的大脑中，其特征是 称为肾小球的突触模块阵列。这些中心被认为是 以化学方式组织，从而在空间上表示气味信息 肾小球之间，但这一重要假设尚未得到检验 全面地在一个具有解剖学简单的优点的物种中， 可识别的肾小球、可接近的受体细胞和中枢神经元，以及 化学鉴定的、与行为相关的气味。此外，尽管戏剧性 化学感应研究取得进展，我们仍然不明白气味有多复杂 刺激被编码在肾小球内部和肾小球之间的神经活动中， 最终导致适当的行为反应。该项目建立在 坚实的技术经验和实验知识基础 有利的模型，Manduca sexta 的嗅觉系统，可与 它在组织和功能上与脊椎动物相对应，并允许 肾小球趋化性假说的测试精度比以往更高 在其他物种中也是可能的。该模型系统还提供了一个特殊的 有机会解开内部和之间的突触神经回路 识别肾小球以揭示特定气味信息的具体情况 在大脑中的第一个中转站进行处理。通过细胞内 记录和染色、细胞外多通道记录、激光扫描 共聚焦和透射电子显微镜以及计算机辅助 数学建模，我们将重点关注可识别的肾小球 聚类：(1) 检验肾小球组织的假设 通过确定化学、时间和强度特性来进行化学定位 行为显着的气味刺激由个体进行分析和编码 神经元支配特定的肾小球； (2)表征突触回路 肾小球内部和肾小球之间，了解各种类型的神经元如何 与肾小球相互作用以塑造输出传达的信号 神经元投射到大脑的高级中心； (3) 发展数学 特征神经元模型，以生成关于其神经元的可检验假设 生理学和突触相互作用。这项研究将促进理解 包括人类在内的所有动物的基本嗅觉机制，并承诺 有助于解释感觉障碍，例如嗅觉异常， 嗅觉减退和嗅觉丧失。