title: Relayed magnetization transfer from nuclear Overhauser effect and chemical exchange observed by in vivo ³¹P MRS in rat brain.
abstract: The (31)P magnetization transfer effects among nuclear magnetic resonances (NMRs) of phosphocreatine (PCr), γ-adenosine-5'-triphosphate (γ-ATP) and inorganic phosphate (Pi) have been attributed to the chemical exchange reactions among PCr, ATP and Pi catalyzed by creatine kinase (CK) and ATPase enzymes and, therefore, are commonly applied in situ to measure chemical exchange fluxes involving two chemically coupled CK and ATPase reactions (i.e., PCr↔ATP↔Pi) by selectively saturating γ-ATP resonance. Besides the expected reductions in the Pi and PCr NMR signals upon saturating γ-ATP resonance, one particularly interesting phenomenon showing decreases in α-ATP and β-ATP signals was also observed. The underlying mechanism was investigated and identified via saturating NMR of β-ATP in the present study. The unique relayed magnetization transfer effects through spin diffusion were observed in the rat brain using in vivo (31)P magnetic resonance spectroscopy.
authors.affiliation: Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota Medical School, Minneapolis, MN 55455, USA. fdu@mclean.harvard.edu
authors.forename: Fei
authors.initials: F
authors.lastname: Du
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
mesh_terms: D000255:Adenosine Triphosphate / Q000032:analysis*; D000818:Animals; D016477:Artifacts; D001923:Brain Chemistry; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D010710:Phosphates / Q000032:analysis*; D010725:Phosphocreatine / Q000032:analysis*; D010758:Phosphorus / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D010710:Phosphates; D010725:Phosphocreatine; D010758:Phosphorus; D000255:Adenosine Triphosphate