Dopamine and serotonin drew much attention to understand a biological mechanism underlying
alchohol dependence. There were three reasons. First, behavioral effects governed by them were quite
similar with various psychopathology observed in alcoholism. Second, preference to alcohol drinking
tended to be related to the genetically transmitted biochemical abnormalities of these neurotransmitters.
Finally, reward-mediating brain areas which seemed to be related to alcoholism were included in
dopaminergic and serotonergic pathways.
The aims of this study were to look for any changes of dopamine and serotonin concentrations in
alcohol dependence, to identify what psychopathology was associated with, and to understand a
biological mechanisms underlying alcohol-related psychopathology.
Subjects were consisted of 25 male patients admitted with alcohol dependence and 25 healthy male
volunteers. Samples drawn after 1 to 3 weeks of detoxification were analyzed by HPLC for the
measurement of plasma dopamine and serotonin concentrations. Otherwise, precise alcohol history
including duration of alcohol drinking, onset age, family history, types of alcoholism, MAST score,
and frequency of hospitalization was done. Furthermore, psychopathology was rated by several questionnares like BPRS, MMPI, Sexual Jealousy Questionnaire, BDI and CES-D.
1) Mean concentration of dopamine in alcoholics(61.8±22.6pg/ml) was significantly(p<0.01)
lower than in controls(77.4±16.3pg/ml), while serotonin concentration in alcoholics tended to be
higher than in controls.
2) Dopamine concentration was negatively correlated with ‘hallucinatory behavior’item(p<0.01)
and ‘unusual thought content’item(p<0.01) of BPRS, and ‘hypochondriasis’scale(p<0.05) of MMPI.
While serotonin concentration was positively correlated with ‘tension’item(p<0.001) of BPRS.
3) Dopamine concentration was negatively correlated with SJQ(p<0.05), while serotonin concentration was positively correlated with frequency of hospitalization(p<0.05) and total score of BPRS
(p<0.001).
In conclusion, reduced dopamine and increased serotonin concentrations seemed to be associated
with psychosis developed in alcohol dependence. Otherwise, impulsivity-aggressivity easily found in
alcoholics might be biologically related to decreased dopamine concentration.