Open Access1H-Observe/13C-decouple spectroscopic measurements of lactate and glutamate in the rat brain in vivo.
Author(s) -
Douglas L. Rothman,
Kevin L. Behar,
Hoby P. Hetherington,
Jan A. den Hollander,
M.Robin Bendall,
Ognen A. C. Petroff,
Robert G. Shulman
Publication year - 1985
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.82.6.1633
Subject(s) - in vivo , glutamate receptor , carbon 13 nmr , glycogen , chemistry , nuclear magnetic resonance spectroscopy , nuclear magnetic resonance , biology , biochemistry , stereochemistry , physics , receptor , microbiology and biotechnology
We have used (13C)-1H NMR spectroscopy at 360.13 MHz to resolve the 13C coupled proton resonance of glutamate and lactate in the rat brain in vivo. The time required for the 13C fractional enrichment of the 4-CH2 position of brain glutamate to reach isotopic steady state was determined during a continuous infusion of D-[1-13C]glucose. Under conditions of ischemia, measurements made of the 3-CH3 of lactate in (13C)-1H NMR spectra revealed the relative contribution of brain glucose and glycogen to lactate formation. (13C)-1H NMR was 11 times more sensitive than 13C NMR for the detection of 13C in the 3-CH3 position of lactate and 6 times more sensitive for the detection of 13C in the 4-CH2 of glutamate under similar in vivo conditions.