Reduced levels of GABA-benzodiazepine receptor in alcohol dependency in the absence of grey matter atrophy.
BACKGROUND
We tested the hypothesis that reduced levels of the GABA-benzodiazepine receptor occur in alcohol dependency using single photon emission tomography (SPET) and the specific GABA-benzodiazepine ligand, 123I-iomazenil.


METHODS
Neurologically and cognitively unimpaired abstinent alcohol-dependent (n = 12) and non-alcohol-dependent male subject (n = 14) underwent a 123I-iomazenil SPET scan. SPET and magnetic resonance images were co-registered and voxel-based statistical tests performed. Subjects' clinical and alcohol history were obtained with standard questionnaires. The relationships between clinical and alcohol variables and the regional level of GABA-benzodiazepine receptors were investigated using multiple regression analysis.


RESULTS
Abstinent alcohol-dependent subjects had decreased levels of GABA-benzodiazepine receptor compared with non-alcohol-dependent subjects within the frontal, parietal and temporal cortices, including regions in which grey matter atrophy was absent.


CONCLUSIONS
Alcohol dependency is associated with reduced GABA-benzodiazepine receptor levels in the absence of grey matter atrophy in some cortical regions, such as within the parietal lobe. Regional variability of reduction in GABA-benzodiazepine receptors demonstrates that alcohol does not have a global, toxic effect on the brain.
Lingford-Hughes
A R
AR
Department of Psychological Medicine, Institute of Psychiatry, London. sphaarl@iop.bpmf.ac.uk
Acton
P D
PD
Gacinovic
S
S
Suckling
J
J
Busatto
G F
GF
Boddington
S J
SJ
Bullmore
E
E
Woodruff
P W
PW
Costa
D C
DC
Pilowsky
L S
LS
Ell
P J
PJ
Marshall
E J
EJ
Kerwin
R W
RW
D000328:Adult; D000437:Alcoholism / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology; D001284:Atrophy; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D011963:Receptors, GABA-A / Q000378:metabolism*; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods
D011963:Receptors, GABA-A