The effects of neurotoxins 6-hydroxydopamine and 5,7-dihydroxytryptamine into the rat nucleus accumbens on the alcohol drinking behavior
Yoshimoto, K.; Kawamura, K.; Yayama, K.; Fujimiya, T.; Uemura, K.; Komura, S.
Nihon Hoigaku Zasshi 49(1): 11-19
1995
ISSN/ISBN: 0047-1887 PMID: 7723195 Document Number: 451053
To elucidate the relationship between drinking behavior and brain monoamines in the brain rewarding system, the effects of injection of 6-hydroxydopamine (6-OHDA) and 5,7-dihydroxytryptamine (5,7-DHT) into the rat nucleus accumbens (ACC), which would affect dopamine- and indoleamine-containing neurons, respectively, on the rat alcohol preference score were examined. The 6-OHDA (4 micrograms/side)-treated rats showed a higher alcohol preference score for 2 weeks following the treatment, and a lowered dopamine (DA) level in the ACC and midbrain after ACC injection of 6-OHDA. On the other hand, although the serotonin (5-HT) and DA levels in the midbrain and 5-HT level in ACC were lowered after the injection of 5,7-DHT, the alcohol preference score was not significantly changed in the 5,7-DHT (4 micrograms/side)-treated rats. Taken together, these findings suggest that the alcohol drinking behavior is more influenced by the ACC DA activity than 5-HT activity. Changes in alcohol drinking behavior might be related to the compensatory mechanism for the rat to restore the original rewarding properties.