Metabolic changes within the left dorsolateral prefrontal cortex occurring with electroconvulsive therapy in patients with treatment resistant unipolar depression.
BACKGROUND
The dorsolateral prefrontal cortex (DLPFC) is involved in the pathophysiology of major depression. In particular, metabolic (functional hypometabolism) and structural alterations have been described. In this study metabolic changes within the DLPFC of severely depressed patients before and after electroconvulsive therapy (ECT) were evaluated by proton STEAM spectroscopy (1H-MRS).


METHODS
Twelve severely depressed patients with a diagnosis of major depressive episode, unipolar with melancholic features (DSM-IV), were enrolled, and the left dorsolateral prefrontal cortex (DLPFC) was investigated before and after unilateral ECT by 1H-MRS. Three of the four non-responding patients were remeasured a third time after a combined ECT/antidepressant pharmacotherapy. The results were compared with 12 age- and gender-matched controls.


RESULTS
In depressed patients reduced glutamate/glutamine (Glx) levels were measured pre-ECT; Glx concentrations correlated negatively with severity of depression. After successful treatment, Glx increased significantly and levels no longer differed from those of age-matched controls.


CONCLUSIONS
Our results indicate that major depressive disorder is accompanied by state-dependent metabolic alterations, especially in glutamate/glutamine metabolism, which can be reversed by successful ECT.
Michael
N
N
Department of Psychiatry, University of Münster, Münster, Germany.
Erfurth
A
A
Ohrmann
P
P
Arolt
V
V
Heindel
W
W
Pfleiderer
B
B
D000368:Aged; D001931:Brain Mapping; D003865:Major Depressive Disorder / Q000503:physiopathology / Q000628:therapy*; D004292:Dominance, Cerebral / Q000502:physiology*; D004565:Electroconvulsive Therapy; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D018698:Glutamic Acid / Q000378:metabolism; D005973:Glutamine / Q000378:metabolism; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D017397:Prefrontal Cortex / Q000503:physiopathology*; D012016:Reference Values
D005973:Glutamine; D018698:Glutamic Acid