Glutamate cycle changes in the putamen of patients with de novo Parkinson's disease using 1H MRS

To investigate glutamatergic metabolism changes in the putamen of patients with de novo Parkinson's Disease (PD) and test the hypothesis that glutamate (Glu) levels are abnormally elevated in the putamen contralateral to where the motor clinical signs predominate as expected from observations in animal models. 1H NMR spectra from 17 healthy control volunteers were compared with spectra from 17 de novo PD patients of who 14 were evaluated again after 2–3 years of disease progression. Statistical analysis used random-effects models. The only significant difference between PD patients and controls was a higher glutamine (Gln) concentration in the putamen ipsilateral to the hemibody with predominant motor signs (Visit 1: 6.0 ± 0.4 mM vs. 5.2 ± 0.2 mM, p