NMR indirect detection of glutamate to measure citric acid cycle flux in the isolated perfused mouse heart

FEBS Lett. 2001 Sep 7;505(1):163-7. doi: 10.1016/s0014-5793(01)02799-5.

Abstract

(13)C-edited proton nuclear magnetic resonance (NMR) spectroscopy was used to follow enrichment of glutamate C3 and C4 with a temporal resolution of approximately 20 s in mouse hearts perfused with (13)C-enriched substrates. A fit of the NMR data to a kinetic model of the tricarboxylic acid (TCA) cycle and related exchange reactions yielded TCA cycle (V(tca)) and exchange (V(x)) fluxes between alpha-ketoglutarate and glutamate. These fluxes were substrate-dependent and decreased in the order acetate (V(tca)=14.1 micromol g(-1) min(-1); V(x)=26.5 micromol g(-1) min(-1))>octanoate (V(tca)=6.0 micromol g(-1) min(-1); V(x)=16.1 micromol g(-1) min(-1))>lactate (V(tca)=4.2 micromol g(-1) min(-1); V(x)=6.3 micromol g(-1) min(-1)).

Publication types

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

MeSH terms

  • Animals
  • Citric Acid Cycle / physiology*
  • Female
  • Glutamic Acid / analysis*
  • Glutamic Acid / metabolism
  • In Vitro Techniques
  • Ketoglutaric Acids / metabolism
  • Magnetic Resonance Spectroscopy / methods*
  • Mice
  • Myocardium / metabolism*
  • Oxygen Consumption
  • Perfusion
  • Sensitivity and Specificity

Substances

  • Ketoglutaric Acids
  • Glutamic Acid