EPR imaging for in vivo analysis of the half-life of a nitroxide radical in the hippocampus and cerebral cortex of rats after epileptic seizures

Electron Spin Relaxation Time Measurements Using Radiofrequency Longitudinally Detected ESR and Application in Oximetry

“…ESR techniques can detect unpaired electrons of free radicals directly (1,2) and perform an indirect assessment of pO 2 , microviscosity, and pH in vivo by means of measurements of certain spectral parameters such as electron relaxation times and hyperfine constants (3,4). These applications are of particular clinical interest in providing noninvasive, repetitive, rapid, sensitive, and quantitative measurements (5).…”

Effect of chronic hypoxia on glutathione status and membrane integrity in the pancreas

“…For example, tirapazamine, a bio-reductive anticancer drug, induces DNA damage selectively in hypoxic cells by the generation of free radicals within the nucleus [29]. It could also be plausible that most reactive radicals have a very short half-life and site of action so they do not cause oxidative damage to the lipid membranes if the cytosolic antioxidant system can cope with the rate of free radical formation [30]. It has been demonstrated that a mild oxidative insult only lowered hydrosoluble antioxidants without affecting the level of MDA [31,32].…”

In Vivo Imaging of Renal Redox Status during Azelnidipine Treatment

“…Applications of EPR for in vivo measurements has been difficult because 1) the absolute concentration of biological radicals in a steady condition is quite low and 2) microwaves used in the conventional X-band EPR system causes dielectric loss by body fluid. The recent development of a nitroxyl radical-spin probe method and low-frequency L-band EPR has circumvented these problems and in vivo EPR measurement is coming into use (4)(5)(6)(7)(8)(9)(10)(11). In the EPR spin probe method, a paramagnetically stable spin probe, which is EPR-positive in stable conditions, is injected into the animals.…”