ESR ANALYSIS AND IN VIVO ACTION OF ENDOGENOUS NITRIC OXIDE

内源性一氧化氮的 ESR 分析和体内作用

基本信息

批准号：
10044107
负责人：
YOSHIMURA Tetsuhiko
金额：
$ 2.18万
依托单位：
INSTITUTE FOR LIFE SUPPORT TECHNOLOGY (ILST)
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B).
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

项目摘要

A variety of information about physiological and pathological actions of nitric oxide has been found very useful for the development of drugs as Viagra. To elucidate a variety of actions of endogenous NO, information concerning the quantities and distributions of NO in cells, tissues, and organs is essential. However, it is rather difficult to determine quantities and distribution due to the very small concentration of NO formed in vivo and the very short half-life of NO in living system. As one of the analytical methods to overcome these difficulties, spin-trapping technique combined with electron paramagnetic resonance (EPR) spectroscopy has been used for the determination of unstable free radicals in vitro and in vivo.1. Iron complexes with dithiocarbamate derivatives are noted among the spin trapping reagents for NO because NO has a high affinity for the iron complexes and resultant NO-bound iron complexes exhibit an intense three-line signal at room temperature on in vitro EPR mea … More surement. N-(dithiocarboxy) sarcosine (DTCS) is a derivative of dithiocarbamate. We recently reported that iron complex with DTCS (Fe-DTCS) and its NO complex (NO-Fe-DTCS) are fairly soluble and stable in aqueous media and Fe-DTCS complex have a potential as a biologically benign, effective NO-trapping reagent. In this study, we measured endogenously produced nitric oxide by employing EPR spin-trapping technique and iron complex with dithiocarbamate as an NO trapping agent. First, we tried in vivo detection of nitric oxide in the brain of living rat during experimental sepsis and meningitis. It was demonstrated that NO is generated in vivo by inducible NO synthase in the brain during sepsis and meningitis. Second, we measured NO production from a nitrovasodilator, isosorbide dinitrate, in mice by in vivo EPR spectroscopy and obtained three-dimensional EPR images of the upper abdominal region.2. This project was started as a joint research of International Scientific Research Program in 1998. We collaborated with Dr. Yashige Kotate of Oklahoma Medical Research Foundation in USA. In this joint research, we investigated the pharmacological activities of a spin-trapping agent, phenyl-N-tert-butyl nitrone (PBN) in various biological systems. The results obtained suggested that PBN has the function like a non-steroidal anti-inflammatory drug and it reduces the nitric oxide production in the rat brain of meningitis model. Less

人们发现有关一氧化氮生理和病理作用的各种信息对于开发伟哥等药物非常有用。为了阐明内源性一氧化氮的各种作用，有关细胞、组织和器官中一氧化氮的数量和分布的信息。然而，由于体内形成的NO浓度非常小，且其在生命系统中的半衰期非常短，因此确定其数量和分布相当困难，而旋转是克服这些困难的分析方法之一。 - 结合捕获技术电子顺磁共振 (EPR) 光谱已用于体外和体内测定不稳定的自由基。 1. 铁与二硫代氨基甲酸盐衍生物的配合物被认为是 NO 自旋捕获试剂，因为 NO 对铁配合物具有高亲和力。所得的 NO 结合铁络合物在室温下在体外 EPR 测量中表现出强烈的三线信号，确定 N-（二硫羧基）肌氨酸（DTCS）。我们最近报道了铁与 DTCS 的络合物 (Fe-DTCS) 及其 NO 络合物 (NO-Fe-DTCS) 在水性介质中相当可溶且稳定，并且 Fe-DTCS 络合物具有作为生物良性、在本研究中，我们采用 EPR 自旋捕获技术和二硫代氨基甲酸铁络合物作为 NO 捕获剂来测量内源性一氧化氮。我们尝试在实验性脓毒症和脑膜炎期间对活体大鼠大脑中的一氧化氮进行体内检测，结果表明，在脓毒症和脑膜炎期间，NO 是由大脑中的诱导型 NO 合酶产生的。硝酸异山梨酯在小鼠体内进行体内EPR光谱分析，获得上腹部三维EPR图像。2． 1998年，我们与美国俄克拉荷马州医学研究基金会的Yashige Kotate博士合作，在这项联合研究中，我们研究了自旋捕获剂苯基-N-叔丁基硝酮（PBN）在各种生物系统中的药理活性。所得结果表明，PBN具有类似非甾体抗炎药的功能，它可以减少脑膜炎模型大鼠大脑中一氧化氮的产生。