The role of serotonin in drug use and addiction.
The use of psychoactive drugs is a wide spread behaviour in human societies. The systematic use of a drug requires the establishment of different drug use-associated behaviours which need to be learned and controlled. However, controlled drug use may develop into compulsive drug use and addiction, a major psychiatric disorder with severe consequences for the individual and society. Here we review the role of the serotonergic (5-HT) system in the establishment of drug use-associated behaviours on the one hand and the transition and maintenance of addiction on the other hand for the drugs: cocaine, amphetamine, methamphetamine, MDMA (ecstasy), morphine/heroin, cannabis, alcohol, and nicotine. Results show a crucial, but distinct involvement of the 5-HT system in both processes with considerable overlap between psychostimulant and opioidergic drugs and alcohol. A new functional model suggests specific adaptations in the 5-HT system, which coincide with the establishment of controlled drug use-associated behaviours. These serotonergic adaptations render the nervous system susceptible to the transition to compulsive drug use behaviours and often overlap with genetic risk factors for addiction. Altogether we suggest a new trajectory by which serotonergic neuroadaptations induced by first drug exposure pave the way for the establishment of addiction.
Department of Psychiatry and Psychotherapy, University Clinic, Friedrich-Alexander-University Erlangen-Nuremberg, Schwabachanlage 6, 91054 Erlangen, Germany. Electronic address: Christian.Mueller@uk-erlangen.de.
Christian P
CP
Müller
Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Centre, Geert Grooteplein 21, Nijmegen 6525 EZ, Netherlands.
Judith R
JR
Homberg
D000818:Animals; D016739:Behavior, Addictive / Q000523:psychology*; D001921:Brain / Q000187:drug effects*; D000697:Central Nervous System Stimulants / Q000494:pharmacology; D004195:Disease Models, Animal; D006801:Humans; D012701:Serotonin / Q000378:metabolism*; D019966:Substance-Related Disorders / Q000378:metabolism* / Q000503:physiopathology
D000697:Central Nervous System Stimulants; D012701:Serotonin
Abuse; Addiction; Animal model; Genetic risk; Psychoactive drug; Serotonin