1H MRS brain measures and acute lorazepam administration in healthy human subjects

The effects of acute lorazepam administration on 1H magnetic resonance spectroscopy (MRS) in vivo brain spectra were examined in the left dorsolateral prefrontal cortex (L-DLPFC) of healthy human subjects. We wanted to examine whether lorazepam administration would result in significant changes in the levels of 1H-MRS metabolites in this brain region. Ten healthy controls underwent a short echo-time 1H-MRS session immediately before, and a second one 1 h after lorazepam administration (2mg/orally). The measured 1H-metabolites included N-acetyl-aspartate, phosphocreatine+creatine, trimethylamines, myo-inositol, glutamate, and glutamine, which were expressed as absolute values and ratios. No significant differences were found after lorazepam administration for any of the measured metabolite levels or ratios (paired t-tests, p >.05). This study demonstrated that lorazepam can potentially be utilized to acutely sedate psychiatric subjects during in vivo 1H-MRS sessions, as it does not appear to produce significant changes in the 1H-MRS spectra in this specific brain region.