Analysis of free radical reactions in diseases model animals using in vivo ESRI

据报道，自由基与糖尿病、高血压、脑血管意外和癌症等多种疾病有关。在这项研究中，我们利用体内ESR/自旋探针技术研究了自由基的产生与疾病发生/发展的关系。N-二乙基亚硝胺(DEN)处理组膜透性氮氧基探针MC-PROXYL的ESR信号衰减率高于对照组，而膜通透性较差的氨基甲酰-PROXYL在DEN处理组的ESR信号衰减率没有变化，表明DEN处理的大鼠肝脏细胞内产生了活性氧物种。OMRI是一种新开发的成像设备，使我们能够获得空间分辨率更高、测量时间更短的自由基图像。我们开发了分子成像系统，用…同时显示细胞内和细胞外的氧化还原反应更多^&lt；14&gt；N-或^&lt；15&gt；N标记的氮氧基探针。含有抗坏血酸脂质体和膜透过性基团而不是膜不通透性基团的幻影对象显示OMRI图像强度随时间的降低。该OMRI系统被应用于非甾体抗炎药诱导的胃溃疡和溃疡性结肠炎等实验性疾病模型的体内自由基检测，并获得了疾病发展引起的细胞内和/或细胞外的增强自由基生成的在体标测。然而，0.015 T OMRI的图像具有较低的时间和空间分辨率，导致其磁共振成像磁场太低而导致解剖信息不准确。因此，本研究开发了0.4T的样品传输OMRI系统。该模型由直径2.0 mm、壁厚0.35 mm的圆柱形草管和装满氮氧自由基溶液的矩形容器组成，得到了清晰的图像

Free radical is reportedly associated with various diseases such as diabetes, hypertension, cerebrovascular accident, and cancer. In this study, we investigated the relationship between free radical generation and the initiation/development of diseases using in vivo ESR/spin probe technique. The ESR signal decay rate of MC-PROXYL, which is a membrane-permeable nitroxyl probe, in N-diethylnitrosoamine (DEN)-treated group is enhanced compared with that in control group, while the ESR signal decay rate of carbamoyl-PROXYL, which is a less membrane-permeable probe, in DEN-treated group is not changed, suggesting that reactive oxygen species is generated at the intracellular compartment of liver in DEN-treated rat.OMRI is a newly developed imaging apparatus, which enables us to get free radical images with higher space resolution and shorter measuring time. We developed the molecular imaging system that is to visualize the redox reactions between in cell and out of cell simultaneously with … More ^<14>N-or ^<15>N-labeled nitroxyl probes. Phantom objects containing ascorbic acid-encapsulated liposomes with membrane-permeable radicals but not membrane-impermeable ones show a time-dependent decrease of the OMRI image intensity. This OMRI system was applied to the in vivo free radical detection of experimental disease models such as NSAIDs-induced gastric ulcer and ulcerative colitis, and in vivo mapping of enhanced radical generation at the intra-cellular compartment and/or the extra-cellular compartment that was induced by the development of disease was obtainedHowever, the images of 0.015 T OMRI have low time and space resolution, resulting in the inaccurate anatomical information because its MRI magnetic field is too low. So, in this study sample transport OMRI system having 0.4 T was developed. The clear image of the phantom, which is composed of cylindrical grass tube (diameter 2.0 mm, wall thickness 0.35 mm) and rectangular container filled with nitroxyl radical solution, was obtained using this sample transport OMRI Less