In Vivo L-COSY MR Distinguishes Glutamate from Glutamine and Shows Neuropathic Pain to Cause a Buildup of Glutamine in the Brain

Alexander Peter Lin¹, Saadallah Ramadan¹, Peter Stanwell¹, Tuan Luu¹, James Celestin², Zahid Bajwa², Carolyn Mountford¹

This study utilizes two-dimensional (2D) COrrelated SpectroscopY (COSY) to allow, in a clinically accepted time, detailed chemical information to be collected in situ from the brain. 2D COSY can in theory separate the glutamate and glutamine resonances by measuring distinct scalar coupling. These metabolites are neurotransmitters and affected by a number of diseases. For the first time we successfully distinguished between glutamine and glutamate using 2D COSY and show that glutamine is present in higher quantities in subjects with neuropathic pain.