title: Spatially resolved time-course studies of free radical reactions with an EPRI/MRI fusion technique.
abstract: Electron paramagnetic resonance imaging (EPRI) using nitroxyl radicals is a useful technique for visualizing reactive oxygen species (ROS) and the pharmacokinetics of probes. To unambiguously identify anatomical locations, coregistration of EPRI with images obtained by MRI is necessary. In this study the feasibility of performing reliable EPRI/MRI fusion imaging using nitroxyl radical fiducial markers was tested. The pharmacokinetics of the nitroxyl radicals were observed after oral or intravenous administration in C57BL6 mice. To fuse both images, the nitroxyl radical was used as fiducial markers. The EPR and MR images corresponded well and clearly illustrated minimal changes in pharmacokinetics between carbamoyl-PROXYL and carboxy-PROXYL. These results demonstrate that the EPRI/MRI fused imaging technique is useful for investigating in vivo pharmacokinetics and provides unambiguous anatomic details.
authors.affiliation: Department of Bio-function Science, Faculty of Pharmaceutical Sciences, Kyushu University, Higashi-ku, Fukuoka, Japan.
authors.forename: Fuminori
authors.initials: F
authors.lastname: Hyodo
authors.forename: Keiji
authors.initials: K
authors.lastname: Yasukawa
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Yamada
authors.forename: Hideo
authors.initials: H
authors.lastname: Utsumi
mesh_terms: D000818:Animals; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D005240:Feasibility Studies; D005609:Free Radicals / Q000493:pharmacokinetics*; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D051379:Mice; D008810:Mice, Inbred C57BL; D009589:Nitrogen Oxides / Q000493:pharmacokinetics*; D019047:Phantoms, Imaging; D013113:Spin Labels
chemical_list: D005609:Free Radicals; D009589:Nitrogen Oxides; D013113:Spin Labels; C039900:nitroxyl