Identification of neurotransmitter receptor genes involved in alcohol self-administration in the rat prefrontal cortex, hippocampus and amygdala

• About half of the risk to develop alcoholism is related to genetic background and it is well known that alcohol consumption is highly individualized. In this study, we investigated how individual alcohol consumption behaviour in Wistar rats correlated with mRNA expression of 20 genes in the prefrontal cortex, hippocampus and amygdala. We found that the long-term alcohol consumption of an individual could be estimated by the mean of its consumption on Day 2 and 3. This short exposure minimized changes in gene expression induced by alcohol itself. We found a positive correlation in the prefrontal cortex of GABAA α5 (r = 0.96), GABAB1 (r = 0.96), AMPA GluR1 (r = 0.93), 5-HT3A (r = 0.93) and the α adrenoceptors (α1A r = 1.00, α1B r = 0.93, α2A r = 0.93) with consumption. In the hippocampus, we found negative correlations with the NMDA NR2A subunit (r = − 0.86), the α1A adrenoceptor (r = − 0.89) and the glucocorticoid receptor (r = − 0.86). Finally, in the amygdala there was a negative correlation to NMDA NR2A (r = − 0.79) and a positive correlation with serotonin 5-HT2C (r = 0.79). In conclusion, we have used qPCR to identify specific genes in the brain that correlated to alcohol self-administration of an individual animal. This study suggests that alcohol consumption in the early stages of acquisition depends on the genetic background of the individual and that the prefrontal cortex is particularly important in this behaviour.

Nyckelord

Alcohol Drinking/*genetics

Amygdala/*metabolism

Animals

Conditioning; Operant/drug effects/physiology

DNA Primers

DNA; Complementary/biosynthesis

Drinking Behavior/drug effects

Gene Expression/physiology

Hippocampus/*metabolism

Male

Prefrontal Cortex/*metabolism

RNA/biosynthesis/isolation & purification

Rats

Rats; Wistar

Receptors; Neurotransmitter/*genetics

Reverse Transcriptase Polymerase Chain Reaction

Saccharin/pharmacology

MEDICINE

MEDICIN

Publikations- och innehållstyp

ref (ämneskategori)

for (ämneskategori)