DEVELOPMENT OF EPR CATHETER PROBES FOR IN VIVO STUDIES

用于体内研究的 EPR 导管探针的开发

• 批准号: 6353189
• 负责人: TADEUSZ WALCZAK
• 金额: $ 1.22万
• 依托单位: DARTMOUTH COLLEGE
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-09-01 至 2002-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6353189
• 关键词: Mammalia; biological products; biomaterials; biomedical resource; environmental toxicology; enzymes; hematology

Although nitric oxide (NO) is a central mediator during endotoxin-induced sepsis, direct detection of tissue NO in vivo, has until recently been difficult, and techniques have relied on indirect measurement of byproducts in blood or invasive technology. We have utilized electron paramagnetic resonance (EPR) in conjunction with the spin-trapping technique to detect NO directly, and non-invasively, from the tissue of septic mice. Relative signal intensity arising from NO complexed with iron and diethyldithiocarbamate (DETC) measured directly from the liver and kidney of mice given endotoxin was maximal at 6 hours post endotoxin. The quality of the EPR signal obtained (high signal to noise ratio of 15:1) using our experimental set-up and L-band EPR hardware was such that we were able to establish a time course of NO production in tissue following endotoxin, and measurement of NO from other organs (kidney and spleen). This technique was extended to experiments in which we first implanted an oxygen sensitive material (gloxy) into the liver of mice, and then monitored NO production following endotoxin. Due to the fact that the EPR spectrum from gloxy and that of NO-Fe-(DETC)2 do not overlap, we were able to monitor NO production and pO2 simulatneously in tissue, in real time.

尽管一氧化氮 (NO) 是过程中的中心介质 内毒素引起的败血症，直接检测体内组织NO，已 直到最近才变得困难，并且技术依赖于间接 血液或侵入技术中副产物的测量。 我们有 利用电子顺磁共振（EPR）与 自旋捕获技术可直接、非侵入性地检测 NO， 来自脓毒症小鼠的组织。 产生的相对信号强度 从 NO 与铁和二乙基二硫代氨基甲酸酯 (DETC) 的络合中测得 直接从小鼠的肝脏和肾脏给予内毒素是最大的 内毒素后6小时。 获得的 EPR 信号的质量 （15:1 的高信噪比）使用我们的实验设置和 L 波段 EPR 硬件使我们能够建立一个时间 内毒素后组织中NO产生的过程和测量 来自其他器官（肾和脾）的 NO。 这项技术是 扩展到我们首先植入氧气的实验 敏感物质（Gloxy）进入小鼠肝脏，然后进行监测 内毒素后不产生。 由于 EPR Glooxy 的光谱和 NO-Fe-(DETC)2 的光谱不重叠，我们是 能够同时监测组织中的 NO 产生和 pO2 即时的。