Implications of Plsasma Dopamine and Serotonin Concentration Changes in Alcohol Dependence

Cheon, Jin Sook; Kim, Hyun Soo; Oh, Byoung Hoon

Abstract

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, psychop-athology 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.