title: In vitro and in vivo measurement of pH and thiols by EPR-based techniques.
abstract: In vitro and in vivo measurements of pH and thiols provide critical information on physiology and pathophysiology of living organisms, particularly related to oxidative stress. Stable nitroxides of imidazoline and imidazolidine types provide the unique possibility of measuring local values of pH and glutathione content in various biological systems, including in vivo studies. The basis for these applications is the observation of specific chemical reactions of these nitroxides with protons or thiols, followed by significant changes in the electron paramagnetic resonance (EPR) spectra of these probes, measured by low-frequency EPR techniques. The applications of some newly developed pH and SH probes in model systems of pharmacological interest, biological fluids, tissues, and cells as well as in vivo studies in isolated hearts and in the gut of living animals are discussed.
authors.affiliation: Dorothy M. Davis Heart & Lung Research Institute, The Ohio State University, Columbus, OH 43210, uSA. khramtsov-1@medctr.osu.edu
authors.forename: Valery V
authors.initials: VV
authors.lastname: Khramtsov
authors.forename: Igor A
authors.initials: IA
authors.lastname: Grigor'ev
authors.forename: Margaret A
authors.initials: MA
authors.lastname: Foster
authors.forename: David J
authors.initials: DJ
authors.lastname: Lurie
mesh_terms: D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D005978:Glutathione / Q000737:chemistry; D006801:Humans; D006863:Hydrogen-Ion Concentration; D048288:Imidazolines / Q000737:chemistry; D007700:Kinetics; D008956:Models, Chemical; D009569:Nitric Oxide / Q000737:chemistry; D018384:Oxidative Stress; D012709:Serum Albumin / Q000737:chemistry; D013438:Sulfhydryl Compounds / Q000737:chemistry*
chemical_list: D048288:Imidazolines; D012709:Serum Albumin; D013438:Sulfhydryl Compounds; D009569:Nitric Oxide; D005978:Glutathione