PHYSIOLOGICAL MR STUDIES USING HYPERPOLARIZED 129XE

使用超极化 129XE 进行生理 MR 研究

• 批准号: 2227941
• 负责人: CHARLES S. SPRINGER
• 金额: $ 17.13万
• 依托单位: STATE UNIVERSITY NEW YORK STONY BROOK
• 依托单位国家: 美国
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-04-01 至 2000-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2227941
• 关键词: analytical method; bioimaging /biomedical imaging; brain neoplasms; clinical biomedical equipment; diagnosis quality /standard; laboratory mouse; laboratory rat; magnetic resonance imaging; noninvasive diagnosis; nuclear magnetic resonance spectroscopy; phantom model; physiology; technology /technique; technology /technique development; vibrissae; xenon

The noble gas xenon is a safe and effective general anesthetic. Rapidly absorbed via the lung into the blood-stream, it concentrates in lipid- rich tissue with a time-dependence related to blood flow. A major isotope, Xe, has a spin 1/2 nucleus with a chemical shift remarkably sensitive to van de Waals environment (range, 300 ppm). Its T and T values are quite sensitive to O2 concentration and other factors. The crucial point is that, prior to administration, Xe can readily be hyperpolarized, 105-106 fold by spin exchange with optically pumped rubidium: its NMR signal strength (and thus time and space resolution) at 20 mM, would be comparable to that of tissue water proton at 80-100 M: This unique property of Xe, as well as its distinctly different behavior compared to H2O in(a) cell and tissue compartmentalization, (b) and subcellular exchange kinetics, will provide a new adequate quantities of hyperpolarized Ce (Xet). Procedures for imaging, Combined Spectroscopy and Imaging (CIS), and image-guided analysis of local T and T probability distributions (Relaxography), well-established in our laboratory for H and Na, will be applied to the new modality. Parameters for determining and optimizing time and space resolution will be obtained using pattern-drilled Teflon phantoms for Xegas. Parameters for CSI will be obtained using a water-octanol-gas phantom. Overall behavior in the mouse will assayed in several large voxels-the lung gas space, the whole brain, and a large muscle. The dynamics of Xe exchange, compartmentalization and relaxation at the cellular and subcellular level will be determined from the behavior of the chemical shift, line shape, T and T2 in nonimaging studies of model systems of hierachiacal complexity, for a range of O2 concentrations. The dynamics of transport, distribution, and lifetime of Xe in the mouse and rat in vivo will be investigated in other major organs, and peripheral tissues. The pharmacokinetics behavior of an anesthetic is important in its own right. Finally, three well-known mouse and rat paradigms will be studied (a) effects of hypoxia, hyperopia and hypercapnia (excess CO2) on blood flow and Xe in brain and elsewhere; (b) effects of stimulating individual mystical vibrissae (facial whiskers) on Xe in the 'barrel field' area of the somatosensory region of the mouse brain; (c) effect on Xe images (correlated with H imaging and CONTIN analysis of T) of development of tumors following injection of 2X10 KHT sarcoma cells into the mouse gastrocnemius, and similar studies with a metastasizing adenocarcinoma and a brain glioma.

高贵的气体氙是一种安全有效的全身麻醉。 迅速 通过肺吸收到血液中，浓缩在脂质中 丰富的组织具有与血流有关的时间依赖性。 专业 同位素XE具有具有化学移位的自旋1/2核 对Van de Waals环境敏感（范围300 ppm）。 它的t和t 值对O2浓度和其他因素非常敏感。 这 关键点是，在管理之前，XE很容易成为 超极化，10​​5-106倍通过旋转交换和光泵 Rubidium：其NMR信号强度（因此时间和空间分辨率） 在20毫米处，将与80-100的组织水质子相媲美 M：XE的独特属性及其明显不同 与（a）细胞和组织分区化中的H2O相比，（b） 和亚细胞交换动力学将提供新的足够数量 超极化CE（XET）。 成像的过程，合并 光谱和成像（顺式）以及对局部t和局部t的图像引导分析 t概率分布（放松学），在我们的 H和NA的实验室将应用于新模式。 参数 为了确定和优化时间和空间分辨率 使用XEGA的图案钻孔的Teflon Phantoms。 CSI的参数将 可以使用水 - 辛醇 - 气体幻影获得。 总体行为 鼠标将在几个大型体素中测定 - 肺气空间，整个 大脑和大肌肉。 XE Exchange的动态， 细胞和亚细胞水平的隔室化和放松 将从化学移位，线形的行为确定 t和t2在高龙模型系统的非成像研究中 对于一系列O2浓度的复杂性。 运输动力， 在小鼠和大鼠体内的分布和XE的寿命将是 在其他主要器官和周围组织中进行了研究。 这 麻醉的药代动力学行为本身很重要。 最后，将研究三个著名的鼠标和大鼠范式（a） 缺氧，甲状腺素和高脑（过量CO2）对血流的影响 和XE在大脑和其他地方； （b）刺激个体的影响 XE的神秘颤音（面晶须） 小鼠大脑的体感区域； （c）对XE图像的影响 （与H成像和t的t分析相关） 将2x10 kHt肉瘤细胞注入小鼠后的肿瘤 胃癌和转移腺癌的类似研究 和脑神经胶质瘤。