Metabolism of [1-13C]-glucose was studied in situ in cat brain using gradient-enhanced proton-detected heteronuclear spectroscopy. Proton detection of [1-13C]-glucose, [3-13C]-lactate, 4-[13C]-glutamine, 4-[13C]-glutamate and the combined signals 2-[13C]-glutamate/glutamine and 3-[13C]-glutamate/glutamine was achieved, despite the fact that some of the associated proton resonances are close to the water signal. Two-dimensional [1H-13C]-spectra demonstrate the possibility of in situ spectral assignment with 1H sensitivity and 13C resolution. Spectroscopic images of glucose and its metabolic products were also acquired, showing the possibility to study spatial dependence of metabolism.