HORMONAL CONTROL OF OLFACTORY LOBE DEVELOPMENT

嗅觉叶发育的激素控制

• 批准号: 3847054
• 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/3847054
• 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.

神经元发育的激素控制在广泛的神经系统中起着重要作用。 各种动物，包括脊椎动物。 最好的理解之一 系统是变态昆虫，其中三种已确定的激素 在变态过程中协调神经系统的重塑。 这些激素，最明显的是蜕皮激素（及其代谢物，20- 羟基蜕皮激素），已被证明在节段体神经节， 对神经元增殖、程序性细胞死亡和生长的影响 和修剪神经元乔木。 本提案中所述的研究 主要研究昆虫脑内神经发育的激素控制。 天蛾（Manduca sexta）大脑的嗅觉（触角）叶 被选中是为了探讨产生于 以前对短距离细胞间相互作用的详细研究， 指导该系统的发展。 其中许多问题还没有 在节段神经节中被问到，所有这些都特别容易处理， 嗅叶。 具体来说，蜕皮激素水平将被操纵 在变态的关键阶段进行实验， 蜕皮激素影响突触发生的时间和位置， 神经胶质细胞在肾小球的形成、发育和神经炎性动脉中， 神经递质机制的发展，以及 嗅觉神经元 这五个发展事件被选中 因为它们跨越不同的细胞类型，不同的发育阶段， 细胞行为的不同方面。 前四个发生在 血液中的蜕皮激素升数正在上升;最后一个以滴度出现 细胞行为的各个方面。 前四个发生作为蜕皮激素升 在血液中的滴度上升;最后一次发生时，滴度回落到 基线。 这些都是嗅觉发展过程中的重要事件 叶，以及它们的时间和对传入轴突长入的依赖性， 详细研究 这项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、生物化学测定和电生理学。 这项研究的结果将扩展知识的过程中， 嗅叶的发展，并将阐明迄今为止 神经系统发育的未探索方面， 荷尔蒙控制 这些研究将使人们更好地了解 激素参与神经胶质以及神经元发育。