A positron emission tomography study of the effects of treatment with valproate on brain 5-HT2A receptors in acute mania.
OBJECTIVE
To examine the effects of treatment with valproate on brain 5-HT2A receptors in acute manic patients using positron emission tomography (PET) and [18F]-setoperone.


METHODS
Patients with DSM-IV bipolar I disorder-manic episode were recruited. Patients were drug free or drug naïve at the time of baseline PET scan. All patients were treated with valproate and one patient received lithium in addition to valproate for 3-5 weeks following which they had a post-treatment PET scan. The effect of treatment on brain 5-HT2A receptor binding was determined using statistical parametric mapping (SPM) and region of interest (ROI) analyses. Of the 12 manic patients recruited, seven patients had both baseline and post-treatment PET scans.


RESULTS
All seven patients improved with treatment and were in remission at the time of the second PET scan. Both SPM and ROI analyses showed that treatment with mood stabilizers had no significant effect on brain 5-HT2A receptor binding in manic patients.


CONCLUSIONS
This study suggests that changes in brain 5-HT2A receptors are not involved in the antimanic effects of mood stabilizers however, we cannot exclude the possibility of 5-HT2A receptor involvement in down-stream signaling pathways.
Yatham
Lakshmi N
LN
Division of Mood Disorders, University of British Columbia, Vancouver, BC, Canada. yatham@interchange.ubc.ca
Liddle
Peter F
PF
Lam
Raymond W
RW
Adam
Michael J
MJ
Solomons
Kevin
K
Chinnapalli
Manjunath
M
Ruth
Thomas J
TJ
D000208:Acute Disease; D000328:Adult; D018692:Antimanic Agents / Q000627:therapeutic use*; D001714:Bipolar Disorder / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000378:metabolism; D001921:Brain / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000378:metabolism; D003287:Contrast Media; D005260:Female; D006801:Humans; D008094:Lithium / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D011744:Pyrimidinones; D044402:Receptor, Serotonin, 5-HT2A / Q000032:analysis / Q000378:metabolism*; D014635:Valproic Acid / Q000627:therapeutic use*
D018692:Antimanic Agents; D003287:Contrast Media; D011744:Pyrimidinones; D044402:Receptor, Serotonin, 5-HT2A; D014635:Valproic Acid; D008094:Lithium; C045359:setoperone