Neurochemical pathology in hippocampus in euthymic patients with bipolar I disorder.
OBJECTIVE
Subcortical regions such as hippocampus, thalamus and ventral putamen are assumed to be involved in the pathophysiology of mood regulation. Disturbed hippocampal neuronal function indicated by reduced N-acetyl-aspartate (NAA) levels in bipolar patients was shown by several studies. Results in thalamus and putamen are inconsistent.


METHODS
N-acetyl-aspartate, choline (Cho), creatine (Cr) and myo-inositol (Ins) were measured in left hippocampus, left thalamus and left putamen using proton magnetic resonance spectroscopy in 13 euthymic patients with bipolar I disorder and 13 pairwise matched healthy control subjects. Metabolic ratios NAA/Cr, NAA/Cho, Cho/Cr and Ins/Cr were calculated.


RESULTS
Patients with bipolar I disorder demonstrated significantly reduced NAA/Cr in the left hippocampus compared with healthy control subjects. No alterations were found in thalamus or putamen.


CONCLUSIONS
We hypothesize that this NAA/Cr reduction might reflect neuronal dysfunction in the left hippocampus in patients with bipolar disorder.
Scherk
H
H
Department of Psychiatry and Psychotherapy, Georg-August-University Goettingen, Goettingen, Germany. hscherk@uni-goettingen.de
Backens
M
M
Schneider-Axmann
T
T
Kemmer
C
C
Usher
J
J
Reith
W
W
Falkai
P
P
Gruber
O
O
D000328:Adult; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D001714:Bipolar Disorder / Q000453:epidemiology / Q000378:metabolism / Q000503:physiopathology; D002794:Choline / Q000378:metabolism*; D003401:Creatine / Q000378:metabolism*; D019263:Dysthymic Disorder / Q000453:epidemiology / Q000378:metabolism / Q000503:physiopathology; D005260:Female; D006624:Hippocampus / Q000378:metabolism* / Q000503:physiopathology*; D006801:Humans; D007294:Inositol / Q000378:metabolism*; D008297:Male; D011699:Putamen / Q000378:metabolism / Q000503:physiopathology; D013788:Thalamus / Q000378:metabolism / Q000503:physiopathology
D001224:Aspartic Acid; D007294:Inositol; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline