title: Electron paramagnetic resonance imaging of nitric oxide organ distribution in lipopolysuccaride treated mice.
abstract: The recent development of electron paramagnetic resonance (EPR) permits its application for in vivo studies of nitric oxide (NO). In this study, we tried to obtain 3D EPR images of endogenous NO in the abdominal organs of lipopolysuccaride (LPS) treated mice. Male ICR mice, each weighing about 30 g, received 10 mg/kg of LPS intraperitoneally. Six hours later, a spin trapping reagent comprised of iron and an N-dithiocarboxy sarcosine complex (Fe(DTCS)2, Fe 200 mM, DTCS/Fe = 3) were injected subcutaneously. Two hours after this treatment, the mice were fixed in a plastic holder and set in the EPR system, equipped with a loop-gap resonator and a 1 GHz microwave. NO was detected as an NO-Fe(DTCS)2 complex, which had a characteristic 3-line EPR spectrum. NO-Fe(DTCS)2 complexes in organ homogenates were also measured using a conventional X-band EPR system. NO-Fe(DTCS)2 spectra were obtained in the upper abdominal area of LPS treated mice at 8 h after the LPS injection. 3D EPR tiled and stereoscopic images of the NO distribution in the hepatic and renal areas were obtained at the same time. The NO-Fe(DTCS)2 distribution in abdominal organs was confirmed in each organ homogenate using conventional X-band EPR. This is the first known EPR image of NO in live mice kidneys.
authors.affiliation: Institute of Clinical Medicine, University of Tsukuba, Japan. aki-hira@md.tsukuba.ac.jp
authors.forename: Aki
authors.initials: A
authors.lastname: Hirayama
authors.forename: Sohji
authors.initials: S
authors.lastname: Nagase
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ueda
authors.forename: Keigyou
authors.initials: K
authors.lastname: Yoh
authors.forename: Takaaki
authors.initials: T
authors.lastname: Oteki
authors.forename: Mami
authors.initials: M
authors.lastname: Obara
authors.forename: Kenji
authors.initials: K
authors.lastname: Takada
authors.forename: Yukari
authors.initials: Y
authors.lastname: Shimozawa
authors.forename: Kazumasa
authors.initials: K
authors.lastname: Aoyagi
authors.forename: Akio
authors.initials: A
authors.lastname: Koyama
mesh_terms: D000818:Animals; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods; D007668:Kidney / Q000378:metabolism; D008070:Lipopolysaccharides / Q000378:metabolism / Q000494:pharmacology*; D008099:Liver / Q000378:metabolism; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D008872:Microwaves; D009569:Nitric Oxide / Q000378:metabolism*; D013997:Time Factors; D014018:Tissue Distribution
chemical_list: D008070:Lipopolysaccharides; D009569:Nitric Oxide