Multiple quantum filtered 23Na NMR spectroscopy of the isolated, perfused rat liver

Magn Reson Med. 1999 Jun;41(6):1127-35. doi: 10.1002/(sici)1522-2594(199906)41:6<1127::aid-mrm8>;2-h.


Isolated, perfused rat livers were examined by single-quantum (SQ) and double-quantum-filtered (DQ-filtered) 23Na spectroscopy during prolonged global ischemia and during perfusion with ouabain, low-buffer potassium, or lithium-enriched buffer. Baseline separation of the intracellular (Na(i)+) and extracellular (Na(e)+) sodium resonances using TmDOTP5- allowed a direct comparison of temporal changes in SQ versus DQ-filtered Na(i)+. The SQ Na(i)+ signal increased approximately 150% during the first 15 min of global ischemia and then remained relatively constant over the next 45 min, while the DQ-filtered signal steadily increased approximately 400% over the same 60 min period. In similar experiments in which all perfusate sodium was replaced by lithium, the DQ-filtered Na(i)+ signal increased approximately 180% over a similar period of ischemia. Exposure of livers to ouabain also resulted in larger increases in DQ-filtered versus SQ signal of Na(i)+. The approximately 290% increase in DQ-filtered sodium observed during perfusion of livers with a hypokalemic buffer (1.2 mM K+) could be completely reversed by continued perfusion with a buffer containing normal levels of K+ (4.7 mM). These data suggest that the DQ-filtered Na(i)+ signal of liver does not simply report an increase in [Na(i)+], but may be exquisitely sensitive to other intracellular events initiated by altered physiology.

Publication types

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

MeSH terms

  • Animals
  • Ischemia / metabolism
  • Lithium / pharmacology
  • Liver / blood supply
  • Liver / drug effects
  • Liver / metabolism*
  • Magnetic Resonance Spectroscopy / methods
  • Male
  • Ouabain / pharmacology
  • Perfusion
  • Potassium / pharmacology
  • Rats
  • Rats, Sprague-Dawley
  • Sodium / metabolism
  • Sodium Isotopes


  • Sodium Isotopes
  • Ouabain
  • Lithium
  • Sodium
  • Potassium