Magnetic coupling between water and creatine protons in human brain and skeletal muscle, as measured using inversion transfer ¹H‐MRS

Using the inversion transfer technique, the possible magnetic coupling between water protons and the protons of low‐molecular weight metabolites was investigated in human brain and skeletal muscle at 1.5 T. The localized 1 H‐MR spectra were recorded at different times after selective inversion of the water resonance. Water inversion led to a significant transient reduction in the signal intensity of the methyl protons of creatine/phosphocreatine, in both tissues. This is indicative of magnetic coupling between the protons of water and those of creatine/phosphocreatine. Neither the choline and N ‐acetylaspartate protons in brain nor the protons of the trimethylammonium pool in skeletal muscle showed a significant magnetic coupling to mobile water.