Effects of DA-Phen, a dopamine-aminoacidic conjugate, on alcohol intake and forced abstinence

The mesolimbic dopamine (DA) system plays a key role in drug reinforcement and is involved in the development of alcohol addiction. Manipulation of the DAergic system represents a promising strategy to control drug-seeking behavior. Previous studies on 2-amino-N-[2-(3,4-dihydroxy-phenyl)-ethyl]-3-phenyl-propionamide (DA-Phen) showed in vivo effects as a DA-ergic modulator. This study was aimed at investigate DA-Phen effects on operant behavior for alcohol seeking behavior, during reinstatement following subsequent periods of alcohol deprivation. For this purpose, male Wistar rats were tested in an operant paradigm of self-administration; behavioral reactivity and anxiety like-behavior during acute abstinence were evaluated. A characterization of DA-Phen CNS targeting by its quantification in the brain was also carried out. Our findings showed that DA-Phen administration was able to reduce relapse in alcohol drinking by 50% and reversed the alterations in behavioral reactivity and emotionality observed during acute abstinence. In conclusion, DA-Phen can reduce reinstatement of alcohol drinking in an operant-drinking paradigm following deprivation periods and reverse abstinence-induced behavioral phenotype. DA-Phen activity seems to be mediated by the modulation of the DAergic transmission. However further studies are needed to characterize DA-Phen pharmacodynamic and pharmacokinetic properties, and its potential therapeutic profile in alcohol addiction.