The Use of Nuclear Magnetic Resonance Rotating Frame Experiments for One Dimensional Discrimination of Metabolites in Tissues

Abstract

Over the last decade nuclear magnetic resonance spectroscopy (MIR) has emerged as the premier tool for the non-invasive study of tissue metabolism and its regulation, for examining cellular energetics, for monitoring physiologically relevant metabolic events, and for the assessment of tissue viability (1–11). This emergence to a position of prominence has occurred despite several restrictions inherent to the technique: observation is limited to NMR-active nuclei such as 1H, 19F, 31P, 23Na, 13C, 15N, and 39K, present in low molecular weight compounds or ions and existing unbound in the tissue milieu, and for the most part at concentration levels exceeding 0.1 mM. Despite these restrictions, NMR spectroscopy has become an extremely powerful tool by virtue of its ability to measure steady state metabolite levels and elucidate metabolic pathways and controls; to monitor intracellular pH; to assess reaction rates and cellular fluxes using specialized IWR techniques; and to perform these experiments in non-invasive, and hence a non-destructive, manner. The important movement of this research to in vivo experiments in animals has been facilitated by the recent development of wide bore, superconducting NMR magnets.