title: Imaging gene-substance interactions: the effect of the DRD2 TaqIA polymorphism and the dopamine agonist bromocriptine on the brain activation during the anticipation of reward.
abstract: Dopamine is known as the main neurotransmitter modulating the activation of the reward system of the brain. The DRD2 TaqIA polymorphism is associated with dopamine D2 receptor density which plays an important role in the context of reward. Persons carrying an A1 allele have a lower D2 receptor density and a higher risk to show substance abuse. The present study was designed to investigate the influence of the DRD2 TaqIA polymorphism and the selective D2 receptor agonist bromociptine on the activation of the reward system by means of functional magnetic resonance imaging (fMRI). In a double-blind crossover study with 24 participants we found an increase of reward system activation from placebo to bromocriptine only in subjects carrying the A1 allele. Furthermore, only A1 carrier showed an increase of performance under bromocriptine. The results are interpreted as reflecting a specific sensitivity for dopamine agonists in persons carrying an A1 allele and may complement actual data and theories of the development of addiction disorders postulating a higher genetic risk for substance abuse in carrier of the A1 allele.
authors.affiliation: Center for Psychiatry, Justus-Liebig-University Giessen, Am Steg 28, D-35385 Giessen, Germany. peter.kirsch@psychiat.med.uni-giessen.de
authors.forename: Peter
authors.initials: P
authors.lastname: Kirsch
authors.forename: Martin
authors.initials: M
authors.lastname: Reuter
authors.forename: Daniela
authors.initials: D
authors.lastname: Mier
authors.forename: Tina
authors.initials: T
authors.lastname: Lonsdorf
authors.forename: Rudolf
authors.initials: R
authors.lastname: Stark
authors.forename: Bernd
authors.initials: B
authors.lastname: Gallhofer
authors.forename: Dieter
authors.initials: D
authors.lastname: Vaitl
authors.forename: Jürgen
authors.initials: J
authors.lastname: Hennig
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000098:blood supply / Q000187:drug effects* / Q000502:physiology; D001971:Bromocriptine / Q000494:pharmacology*; D003430:Cross-Sectional Studies; D018491:Dopamine Agonists / Q000494:pharmacology*; D004311:Double-Blind Method; D030141:Feedback, Psychological / Q000187:drug effects / Q000502:physiology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D010100:Oxygen / Q000097:blood; D011110:Polymorphism, Genetic; D011930:Reaction Time / Q000187:drug effects / Q000235:genetics; D017448:Receptors, Dopamine D2 / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D012201:Reward
chemical_list: D018491:Dopamine Agonists; D017448:Receptors, Dopamine D2; D001971:Bromocriptine; D010100:Oxygen