Positron emission tomography imaging of the serotonin transporter and 5-HT(1A) receptor in alcohol dependence.
BACKGROUND
Rodent models as well as studies in humans have suggested alterations in serotonin (5-HT) innervation and transmission in early-onset genetically determined or type II alcoholism. This study examines two indices of serotonergic transmission, 5-HT transporter levels and 5-HT(1A) availability, in vivo, in type II alcoholism. This is the first report of combined tracers for pre- and postsynaptic serotonergic transmission in the same alcoholic subjects and the first study of 5-HT(1A) receptors in alcoholism.


METHODS
Fourteen alcohol-dependent subjects were scanned (11 with both tracers, 1 with [(11)C]DASB only, and two with [(11)C]WAY100635 only). Twelve healthy control subjects (HC) subjects were scanned with [(11)C]DASB, and another 13 were scanned with [(11)C]WAY100635. Binding potential (BP(p), mL/cm(3)) and the specific to nonspecific partition coefficient (BP(ND), unitless) were derived for both tracers using a two-tissue compartment model and compared with control subjects across different brain regions. Relationships to severity of alcoholism were assessed.


RESULTS
No significant differences were observed in regional BP(p) or BP(ND) between patients and control subjects in any of the regions examined. No significant relationships were observed between regional 5-HT transporter availability, 5-HT(1A) availability, and disease severity, with the exception of a significant negative correlation between 5-HT transporters and years of dependence in amygdala and insula.


CONCLUSIONS
This study did not find alterations in measures of 5-HT(1A) or 5-HT transporter levels in patients with type II alcoholism.
Martinez
Diana
D
Department of Psychiatry, Columbia University College of Physicians and Surgeons, 1051 Riverside Drive, New York, NY 10032, USA. dm437@columbia.edu
Slifstein
Mark
M
Gil
Roberto
R
Hwang
Dah-Ren
DR
Huang
Yiyun
Y
Perez
Audrey
A
Frankle
W Gordon
WG
Laruelle
Marc
M
Krystal
John
J
Abi-Dargham
Anissa
A
D000328:Adult; D000437:Alcoholism / Q000000981:diagnostic imaging / Q000378:metabolism*; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism*; D001931:Brain Mapping; D002250:Carbon Radioisotopes; D016022:Case-Control Studies; D055030:Drug Users; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D044282:Receptor, Serotonin, 5-HT1A / Q000378:metabolism*; D012016:Reference Values; D050486:Serotonin Plasma Membrane Transport Proteins / Q000378:metabolism*; D012720:Severity of Illness Index
D002250:Carbon Radioisotopes; D050486:Serotonin Plasma Membrane Transport Proteins; D044282:Receptor, Serotonin, 5-HT1A