title: Elevated metabolites within dorsolateral prefrontal cortex in rapid cycling bipolar disorder.
abstract: Metabolites within the left dorsolateral prefrontal cortex (DLPFC) of six inpatients with bipolar II rapid cycling (RC) during various mood states (depressed, hypomanic, and euthymic), six depressed inpatients with non-RC bipolar disorder (BIPD), and six healthy controls (HC) were assessed by proton magnetic resonance spectroscopy (MRS). We hypothesized that glutamate/glutamine levels should be altered in RC compared with HC. Patients with RC in contrast to BIPD and HC exhibited elevated levels of N-acetylaspartate (NAA), choline (Cho), creatine (Cr), and glutamate/glutamine (Glx) during all mood states. The Glx levels of BIPD compared with HC did not differ significantly; the other metabolites were increased, though less than in RC patients. Our findings of elevated metabolites in patients with RC, especially Glx as a possible marker of cortical activity, indicate that increased neuronal activity may constitute an important neurobiological feature of RC.
authors.affiliation: Department of Psychiatry, University Hospital Münster, Germany. nikolaus.michael@stiftung-tannenhof.de
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Michael
authors.forename: Andreas
authors.initials: A
authors.lastname: Erfurth
authors.forename: Bettina
authors.initials: B
authors.lastname: Pfleiderer
mesh_terms: D000328:Adult; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D015415:Biomarkers; D001714:Bipolar Disorder / Q000175:diagnosis / Q000378:metabolism* / Q000523:psychology; D001921:Brain / Q000378:metabolism; D002794:Choline / Q000378:metabolism; D003401:Creatine / Q000378:metabolism; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D018698:Glutamic Acid / Q000378:metabolism*; D005973:Glutamine / Q000378:metabolism*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D017397:Prefrontal Cortex / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D005973:Glutamine; D001224:Aspartic Acid; D018698:Glutamic Acid; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline