NEURONAL PLASTICITY AND THYROID HORMONE

神经元可塑性和甲状腺激素

• 批准号: 3410544
• 负责人: SVEN O EBBESSON
• 金额: $ 17.89万
• 依托单位: UNIVERSITY OF ALASKA FAIRBANKS
• 依托单位国家: 美国
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-07-01 至 1990-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3410544
• 关键词: aging; aminoacid; aquatic organism; autoradiography; axon; biological models; brain metabolism; catecholamines; cell differentiation; dendrites; electron microscopy; high performance liquid chromatography; histochemistry /cytochemistry; immunochemistry; medial olfactory area; metamorphosis; microscopy; model design /development; neural information processing; neural plasticity; neuroendocrine system; neurotransmitters; retina; superior colliculus; sympathetic nervous system; synapses; thyroid hormones; thyroid inhibitor; triiodothyronine; tritium

The proposed studies will define the role of thyroid hormone in the sprouting of axons and other circuitry changes during smoltification in coho salmon. The proposal is prompted by preliminary experiments which show that smoltification is associated with 1) dramatic changes in visual and olfactory pathways, 2) increases in brain serotonin content and 3) increases in brain thyroid hormone binding capacity. Smoltification is a metamorphosis in which thyroid hormone plays an important role. It is characterized by 1) changes in behavior, 2) olfactory imprinting on the natal stream, 3) changes in general appearance and 4) changes in osmoregulatory capacity. Smoltification is of particular interest because it appears to be reversible. The proposed research, which is part of a long range plan to develop salmon as a model for research on plasticity, regeneration, and aging of the brain, will include characterizing light microscopic, ultrastructural and chemical changes of the brain during smoltification. The research has direct implications for understanding changes in circuitry in the human brain because the data will provide information about the role of thyroid hormone in neural plasticity. The results will further elucidate what is universal in neural plasticity and what is unique. Changes in circuits are much easier to detect in salmon than any mammalian brain, making the salmon a ideal model for manipulation of sprouting. The proposed experiments will involve a comparison of three populations of salmon. Thyroid inhibited, thyroxine treated, and normal fish will be sampled frequently before, during and after metamorphosis. 1) Changes in olfactory and retinal projections will be determined with HRP, cobalt lysine and electron microscopic techniques. 2) Quantitative ultrastructural studies of the optic tectum will define changes in the synaptic densities and synaptic types. 3) Changes in brain content of catecholamine and amino acid neurotransmitters will be determined with HPLC techniques. 4) Serotonergic and muscarinic cholinergic neurons will be characterized with immunohistochemical and autoradiographic methods. 5) Golgi studies will be carried out in a search for changes in neuronal morphology. 6) Receptor binding kinetics of triiodothyronine will be determined on isolated cell nuclei and quantitative autoradiographic methods will be used to measure changes in thyroid hormone receptor binding capacity on histological sections.

拟议的研究将定义甲状腺激素在 轴突和其他电路的发芽在 Coho鲑鱼中的Smoltification。 该提案是由 初步实验表明Smoltification是 与1）视觉和嗅觉的戏剧性变化有关 途径，2）增加脑血清素含量和3）增加 在脑甲状腺激素结合能力中。 Smoltification是一种甲状腺激素发挥的变形 一个重要的角色。 它的特征是1）行为变化， 2）嗅觉印记在出生流上，3）一般变化 外观和4）渗透调节能力的变化。 Smoltification特别有趣，因为它似乎是 可逆。 拟议的研究是远程计划的一部分 开发鲑鱼作为可塑性研究的模型， 再生和大脑的衰老将包括表征 光显微镜，超微结构和化学变化 示意性时的大脑。 该研究有直接的影响 了解人脑电路的变化，因为 数据将提供有关甲状腺作用的信息 神经可塑性中的激素。 结果将进一步阐明 神经可塑性的通用和独特之处。 更改 在鲑鱼中，在电路中比任何人都容易得多 哺乳动物的大脑，使鲑鱼成为理想的模型 操纵发芽。 提出的实验将涉及三个比较 鲑鱼的种群。 甲状腺抑制，治疗甲状腺素，并 普通鱼会在，期间和之后经常采样 变态。 1）嗅觉和视网膜预测的变化 将用HRP，钴赖氨酸和电子确定 微观技术。 2）定量超微结构研究 视神经系统将定义突触密度的变化和 突触类型。 3）儿茶酚胺和 氨基酸神经递质将用HPLC确定 技术。 4）血清素能和毒蕈碱胆碱能神经元 将以免疫组织化学和 放射自显影方法。 5）高尔基研究将在 寻找神经元形态的变化。 6）受体结合 将在孤立的细胞上确定三碘甲基氨酸的动力学 细胞核和定量放射自显影方法将用于 测量甲状腺激素受体结合能力的变化 组织学部分。