title: Non-invasive determination of metabolite concentrations in human transplanted kidney in vivo by 31P MR spectroscopy.
abstract: OBJECTIVE
  To investigate concentrations of phosphorus-containing metabolites in human transplanted kidney in vivo by quantitative 31P MR spectroscopy (MRS) using surface coils and to compare the obtained values with previous data.
  
  
  METHODS
  In 5 patients with well-functioning transplanted kidneys, 31P spectra were obtained with the three-dimensional localization image-selected in vivo spectroscopy technique applying a protocol for quantitative spectroscopy using surface coils. Relaxation corrected signal intensities determined by time domain fitting were used to derive absolute molar concentrations for phosphate-containing metabolites.
  
  
  RESULTS
  Little or no phosphocreatine in all spectra verified the absence of muscle contamination, confirming proper volume localization. The mean concentrations in the transplanted kidneys were as follows: ATP 1.60 +/- 0.26 mmol/ 1, PDE 2.14 +/- 0.91 mmol/l, Pi 0.66 +/- 0.25 mmol/l, PME 2.32+ /- 0.50 mmol/l. These values are consistent with previously reported values determined by other techniques.
  
  
  CONCLUSIONS
  The non-invasive determination of absolute metabolite concentrations in human kidney using MRS supplements the use of signal intensity ratios to detect pathologic changes in the energy metabolism of transplanted kidneys.
authors.affiliation: Department of Diagnostic Radiology, University of Cologne, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Kugel
authors.lastname: Wittsack H-J
authors.forename: F
authors.initials: F
authors.lastname: Wenzel
authors.forename: D
authors.initials: D
authors.lastname: Stippel
authors.forename: W
authors.initials: W
authors.lastname: Heindel
authors.forename: K
authors.initials: K
authors.lastname: Lackner
mesh_terms: D000255:Adenosine Triphosphate / Q000032:analysis; D000328:Adult; D006801:Humans; D007668:Kidney / Q000737:chemistry*; D016030:Kidney Transplantation; D009682:Magnetic Resonance Spectroscopy; D008875:Middle Aged; D010725:Phosphocreatine / Q000032:analysis; D010758:Phosphorus / Q000032:analysis
chemical_list: D010725:Phosphocreatine; D010758:Phosphorus; D000255:Adenosine Triphosphate