HORMONAL CONTROL OF OLFACTORY LOBE DEVELOPMENT

嗅觉叶发育的激素控制

• 批准号: 3861648
• 负责人: LESLIE P TOLBERT
• 金额: --
• 依托单位: UNIVERSITY OF ARIZONA
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3861648
• 关键词: Lepidoptera; afferent nerve; axon; developmental neurobiology; ecdysone; electron microscopy; electrophysiology; gamma aminobutyrate; glia; hormone regulation /control mechanism; immunocytochemistry; metamorphosis; neural plasticity; neuroendocrine system; neurogenesis; neurotransmitters; olfactory lobe; synaptogenesis

Hormonal control of neuronal development plays an important role in a wide variety of animals, including vertebrates. Among the best understood systems are the metamorphosing insects, where three identified hormones orchestrate the reshaping of the nervous system during metamorphosis. these hormones, most notably ecdysone (and its metabolite, 20- hydroxyecdysone), have been shown in the segmental body ganglia to have effects on neuronal proliferation, programmed cell death, and the growth and pruning of neuronal arbors. The study described in this proposal focusses on hormonal control of neural development within the insect brian. The olfactory (antennal) lobes of the brain of the moth Manduca sexta has been chosen in order to probe specific questions that have arisen from previous detailed studies of short-range intercellular interactions that guide development in that system. Many of these questions have not yet been asked in the segmental ganglia, and all are especially tractable in the olfactory lobes. Specifically, ecdysteroid levels will be manipulated experimentally during critical stages of metamorphosis to ask whether ecdysteroids affect timing and location of synaptogenesis, behavior of glial cells in the formation of glomeruli, development and neuritic arbors, development of neurotransmitter machinery, and onset of responsiveness of olfactory sensory neurons. These five developmental events were chosen because they span different cell types, different developmental stages, and different aspects of cellular behavior. The first four occur as ecdysteroid liters in the blood are rising; the last occurs as titers aspects of cellular behavior. The first four occur as ecdysteroid liters in the blood are rising; the last occurs as titers fall back toward baseline. All are significant events in the development of the olfactory lobe, and their timing and dependence upon afferent-axon ingrowth have been studied in detail. The proposed study will involve light and electron microscopy, intracellular dye-injection, immunocytochemistry and autoradiography, biochemical assays, and electrophysiology. Results of this study will extend knowledge of the processes underlying development of the olfactory lobe, and will shed light on hitherto unexplored aspects of development of the nervous system that may be under hormonal control. The studies will provide a better understanding of hormonal involvement in glial as well as neuronal development.

激素对神经元发育的控制在广泛的 各种动物，包括脊椎动物。在最了解的人中 系统是蜕变的昆虫，在那里有三种确定的荷尔蒙 在变态过程中协调神经系统的重塑。 这些激素，最著名的是蜕皮激素(及其代谢物，20- 羟基蜕皮激素)，已被证明在节段性体神经节中有 对神经元增殖、细胞程序性死亡和生长的影响 以及神经元乔木的修剪。这项提案中描述的研究 专注于昆虫大脑内神经发育的激素控制。 六纹夜蛾大脑的嗅觉(触角)叶有 被选中是为了探讨由以下原因引起的具体问题 之前对细胞间短程相互作用的详细研究 指导该系统的发展。这些问题中有许多还没有 在节段性神经节中被问及，所有这些都特别容易在 嗅叶。具体地说，蜕皮类固醇水平将被操纵 在变态的关键阶段进行实验，询问是否 蜕皮激素影响突触发生的时间和位置，行为 神经胶质细胞在肾小球的形成、发育和神经节形成中的作用 神经递质机制的发展和反应性的开始 嗅觉感觉神经元。这五个发展事件被选为 因为它们跨越不同的细胞类型，不同的发育阶段，以及 细胞行为的不同方面。前四个出现在 血液中的蜕皮类固醇含量正在上升；最后一种是效价 细胞行为的各个方面。前四种以蜕皮类固醇升的形式出现。 在血液中的含量正在上升；最后一种情况发生在滴度回落到 基线。所有这些都是嗅觉发展过程中的重大事件 叶，以及它们的时间和对传入轴突内长的依赖 进行了详细的研究。拟议中的研究将涉及光和电子。 显微镜、细胞内染料注射、免疫细胞化学和 放射自显影，生化分析和电生理学。 这项研究的结果将扩大对潜在过程的了解 嗅叶的发育，并将阐明到目前为止 神经系统发育的未知方面可能会受到 荷尔蒙控制。这些研究将使我们更好地了解 荷尔蒙参与神经胶质细胞和神经元的发育。