The Effect of Insulin Infusion on the Metabolites in Cerebral Tissues Assessed With Proton Magnetic Resonance Spectroscopy in Young Healthy Subjects With High and Low Insulin Sensitivity (original) (raw)

OBJECTIVE Insulin may play important roles in brain metabolism. Proton magnetic resonance spectroscopy (1H-MRS) of the central nervous system gives information on neuronal viability, cellular energy, and membrane status. To elucidate the specific role of insulin action in the brain, we estimated neurometabolites with 1H-MRS and assessed their regulation by insulin infusion and their relationship with insulin sensitivity. RESEARCH DESIGN AND METHODS We studied 16 healthy young men. 1H-MRS was performed at baseline and after 240 min of euglycemic-hyperinsulinemic clamp. Voxels were positioned in the left frontal lobe, left temporal lobe, and left thalamus. The ratios of N-acetylaspartate (NAA), choline-containing compounds (Cho), myo-inositol, and glutamate/glutamine/γ-aminobutyric acid complex (Glx) to creatine (Cr) and nonsuppressed water signal were determined. The participants were divided into subgroups of high (high IS) and low (low IS) insulin sensitivity. RESULTS Baseline neur...