WATER COMPARTMENTALIZATION IN ISCHEMIA

缺血时的水区室化

• 批准号: 6336720
• 负责人: CHARLES NICHOLSON
• 金额: $ 19.33万
• 依托单位: NEW YORK UNIVERSITY SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-06-01 至 2003-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6336720
• 关键词: age difference; body fluid osmolarity; brain cell; cell membrane; cell morphology; cell water; cerebral ischemia /hypoxia; extracellular; glutamate receptor; glutamate transporter; guinea pigs; intracellular transport; kainate; laboratory rat; light scattering; membrane activity; neocortex; osmosis; sectioning

The overall goal of this project is to understand how water shifts between extracellular and intracellular compartments during ischemia, and during changes in the brain microenvironment that mimic ischemic events. Basic experiments will be done to choose and characterize an ischemic slice model and to look at related protocols that cause water movement in both normal and gliotic slices. A set of collaborative investigations with other members of the Center will then capitalize on this basic research. During all experiments data will be gathered on light scattering properties of the tissue and [Na] - [K] content to see if they will provide useful indicators of water behavior. Finally the data will be used to model changes in the geometry the extracellular space. The majority of experiments will use slices from the neocortex of rats, with which we have experience under both normal and ischemic conditions. The slice permits the application of different media and drugs at precisely known concentrations. Water compartmentalization will be measured using a combination of the extracellular TAMA-method, based on ion-selective microelectrodes, and the weighing-drying method. Aim 1. After setting up a reliable ischemic slice model we will determine how water moves in the intracellular and extracellular compartments, determine the role of NaCl entry into cells, and assess the role of extracellular calcium. Aim 2. Elucidates which of the changes in the cellular microenvironment that occur during ischemia cause water movements. We shall use the normal slice and elevate [K+]c block Na-K transport, change osmolarity of bathing medium, add glutamate and NMDA and AMPA blockers. Aim 3. Some of the experiments will be repeated on slices containing predominantly glial cells. Aim 4. (With Dr. Margaret Rice ) Studies the distribution of water in the young adult and ag ed guinea pig brain under normal and ischemic conditions both with and without ascorbate in the bathing medium. Aim 5. (With Dr. Mitchell Chesler) Looks at the relationship between the putative Na+ - HCO3 co-transporter and water compartmentalization in the gliotic slice under normal conditions, ischemia and when Na-K transport is blocked. Aim 6. Measures the light scattering properties of the slice and analyzes the total Na and K content for many of the above experiments to determine if these measures permit a simplified approach to charting water movement between compartments. The accumulated data will be used to test models relating volume fraction and tortuosity in the extracellular space.

这个项目的总体目标是了解水是如何在 缺血期间的细胞外和细胞内隔室，以及 模拟缺血事件的大脑微环境变化。 基本 将进行实验以选择和表征缺血切片模型 并研究在正常情况下导致水运动的相关协议 和神经胶质切片。 一系列与其他机构的合作调查 该中心的成员将利用这一基础研究。 期间 所有的实验数据将收集在光散射特性的 组织和[Na] - [K]含量，看看它们是否能提供有用的指标 水的行为。 最后，这些数据将用于模拟 细胞外空间的几何形状。 大多数实验将使用大鼠新皮层的切片， 我们在正常和缺血条件下都有经验。 该切片允许应用不同的介质和药物， 已知浓度。 水的划分将采用 结合细胞外TAMA方法，基于离子选择性 微电极和称重干燥法。 目标1。 在建立可靠的缺血切片模型后，我们将确定 水是如何在细胞内和细胞外区室中移动的， 确定NaCl进入细胞的作用，并评估 细胞外钙 目标2. 说明了在 在局部缺血期间发生的细胞微环境引起水运动。 我们将使用正常切片并升高[K+]c阻断Na-K转运， 改变浴槽液的渗透压，加入谷氨酸、NMDA和AMPA 阻滞剂。 目标3. 有些实验将在切片上重复进行 主要含有神经胶质细胞。 目标4。 (With玛格丽特·赖斯博士） 研究了幼年豚鼠和老年艾德豚鼠体内水分的分布 在正常和局部缺血条件下，有和没有抗坏血酸 在沐浴介质中。 目标5。 (With米切尔·切斯勒博士） Na+ -HCO 3协同转运蛋白与水的关系 在正常条件下，缺血 以及Na ~+-K ~+转运受阻时。 目标6。 测量光散射 切片的性质，并分析了总钠和钾含量为许多 上述实验以确定这些措施是否允许简化的 绘制舱室间水运动图的方法。 累计 数据将用于测试与体积分数和弯曲度相关的模型， 细胞外空间。