Quantitation of intracellular [Na+] in vivo by using TmDOTP5- as an NMR shift reagent and extracellular marker

J Appl Physiol (1985). 1998 Nov;85(5):1806-12. doi: 10.1152/jappl.1998.85.5.1806.


A method is presented to measure the absolute concentration of intracellular Na+ ([Na+]i) in vivo by using interleaved 23Na- and 31P-nuclear magnetic resonance (NMR) spectroscopy and TmDOTP5- as shift reagent and chemical marker of tissue extracellular space (ECS). The technique was used to determine [Na+]i and relative ECS in livers of control rats (21 +/- 3 and 0.11 +/- 0.02 mM, respectively) and in rats exposed to carbon tetrachloride (103 +/- 29 and 0.23 +/- 0.03 mM, respectively). The NMR measurements were confirmed independently on excised tissue samples by using atomic absorption spectroscopy. The results confirm that TmDOTP5- can be used as a combined cation shift reagent and ECS marker, thereby allowing quantitation of [Na+]i in vivo by NMR.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Calibration
  • Extracellular Space / metabolism*
  • Indicators and Reagents
  • Magnetic Resonance Spectroscopy
  • Male
  • Organometallic Compounds*
  • Organophosphorus Compounds*
  • Phosphorus Radioisotopes
  • Rats
  • Rats, Sprague-Dawley
  • Sodium / metabolism*
  • Sodium Radioisotopes
  • Spectrophotometry, Atomic
  • Thulium


  • Indicators and Reagents
  • Organometallic Compounds
  • Organophosphorus Compounds
  • Phosphorus Radioisotopes
  • Sodium Radioisotopes
  • thulium(III) 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetramethylenephosphonate
  • Thulium
  • Sodium