Increased Cortical GABA Concentrations in Depressed Patients Receiving ECT

OBJECTIVE: Reduced γ-aminobutyric acid (GABA) concentrations have been reported in the plasma, CSF, and cortex of depressed subjects. Of interest is that ECT, one of the most effective treatments for severe refractory depression, produces considerable anticonvulsant effects that may be related to increased GABAergic transmission. The purpose of this study was to determine if cortical GABA concentrations increase following a course of ECT. METHOD: Occipital cortex GABA concentrations in eight depressed patients were measured by using proton magnetic resonance spectroscopy before and after a course of ECT. RESULTS: A significant increase in occipital cortex GABA concentrations was seen following ECT treatment of depression. CONCLUSIONS: Occipital cortex GABA concentrations increase two-fold following ECT. This suggests possible GABAergic involvement in ECT’s mechanism of anticonvulsant and antidepressant actions.