MRS Measurement of GABA and Glutamate-Glutamine in Frontal Cortex in Obsessive-Compulsive Disorder

Lawrence Steven Kegeles^1,2, H. Blair Simpson¹, Xiangling Mao³, Rena Staub¹, Dikoma C. Shungu³

This MRS study addressed GABA and glutamate-glutamine levels in a hypothesized abnormal neurochemical circuit in obsessive-compulsive disorder (OCD). Recent animal and human studies have implicated the glutamate system in OCD in these abnormalities. We used the J edited spin echo difference method to evaluate glutamate-glutamine and GABA in two frontal cortical regions, the anterior cingulate and dorsolateral prefrontal cortex in OCD. We found no differences between OCD subjects and controls in either measure in either brain region, suggesting that further studies are needed to fully characterize the neurochemistry of the hypothesized abnormal circuitry in OCD.