1H-detected in vivo 13C NMR spectroscopy and imaging at 2T magnetic field: efficient monitoring of 13C-labeled metabolites in the rat brain derived from 1-13C-glucose.

Gradient-select hetero-nuclear multiple quantum coherence in nuclear magnetic resonance (NMR) an indirect method of detecting nuclei in low sensitivity by 1H NMR, was used to observe 13C-enriched metabolites in the rat brain in vivo, with a 2 T NMR system. We detected the accumulation of 13C-labeled glucose and its metabolites, glutamine and/or glutamate, in less than 5 min. The extension of this technique to chemical shift imaging permitted the localization of these chemicals in the rat brain. This approach may have various applications for non-invasive monitoring of 13C-labeled compounds in humans and other animals.