title: Effects of dexamphetamine-induced dopamine release on resting-state network connectivity in recreational amphetamine users and healthy controls.
abstract: Dexamphetamine (dAMPH) is not only used for the treatment of attention deficit hyperactivity disorder (ADHD), but also as a recreational drug. Acutely, dAMPH induces release of predominantly dopamine (DA) in the striatum, and in the cortex both DA and noradrenaline. Recent animal studies have shown that chronic dAMPH administration can induce changes in the DA system following long-term exposure, as evidenced by reductions in DA transporters, D2/3 receptors and endogenous DA levels. However, only a limited number of studies have investigated the effects of dAMPH in the human brain. We used a combination of resting-state functional magnetic resonance imaging (rs-fMRI) and [(123)I]IBZM single-photon emission computed tomography (SPECT) (to assess baseline D2/3 receptor binding and DA release) in 15 recreational AMPH users and 20 matched healthy controls to investigate the short-, and long-term effects of AMPH before and after an acute intravenous challenge with dAMPH. We found that acute dAMPH administration reduced functional connectivity in the cortico-striatal-thalamic network. dAMPH-induced DA release, but not DA D2/3 receptor binding, was positively associated with connectivity changes in this network. In addition, acute dAMPH reduced connectivity in default mode networks and salience-executive-networks networks in both groups. In contrast to our hypothesis, no significant group differences were found in any of the rs-fMRI networks investigated, possibly due to lack of sensitivity or compensatory mechanisms. Our findings thus support the use of ICA-based resting-state functional connectivity as a tool to investigate acute, but not chronic, alterations induced by dAMPH on dopaminergic processing in the striatum.
authors.affiliation: Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. a.g.schrantee@amc.uva.nl.|Brain Imaging Center, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. a.g.schrantee@amc.uva.nl.
authors.forename: Anouk
authors.initials: A
authors.lastname: Schrantee
authors.affiliation: Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Bart
authors.initials: B
authors.lastname: Ferguson
authors.affiliation: Department of Sleep and Cognition, Netherlands Institute for Neuroscience, An Institute of The Royal Netherlands Academy of Arts and Sciences, Amsterdam, The Netherlands.
authors.forename: Diederick
authors.initials: D
authors.lastname: Stoffers
authors.affiliation: Brain Imaging Center, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.|Department of Nuclear Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Jan
authors.initials: J
authors.lastname: Booij
authors.affiliation: Institute of Psychology, Leiden University, Leiden, The Netherlands.|Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands.|Leiden Institute for Brain and Cognition, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Serge
authors.initials: S
authors.lastname: Rombouts
authors.affiliation: Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.|Brain Imaging Center, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Liesbeth
authors.initials: L
authors.lastname: Reneman
mesh_terms: D019969:Amphetamine-Related Disorders / Q000503:physiopathology; D001289:Attention Deficit Disorder with Hyperactivity / Q000503:physiopathology; D001921:Brain / Q000187:drug effects / Q000503:physiopathology*; D001931:Brain Mapping; D063132:Connectome / Q000379:methods; D003342:Corpus Striatum / Q000378:metabolism; D003913:Dextroamphetamine / Q000009:adverse effects* / Q000494:pharmacology; D004298:Dopamine / Q000009:adverse effects* / Q000378:metabolism; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009483:Neuropsychological Tests; D017448:Receptors, Dopamine D2 / Q000378:metabolism; D050637:Receptors, Dopamine D3 / Q000378:metabolism; D012146:Rest / Q000502:physiology; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D055815:Young Adult
chemical_list: D017448:Receptors, Dopamine D2; D050637:Receptors, Dopamine D3; D003913:Dextroamphetamine; D004298:Dopamine
keywords: Dopamine; Functional connectivity; Pharmacological MRI; Resting-state fMRI; SPECT