title: Dopamine efflux in response to ultraviolet radiation in addicted sunbed users.
abstract: Compulsive tanning despite awareness of ultraviolet radiation (UVR) carcinogenicity may represent an "addictive" behavior. Many addictive disorders are associated with alterations in dopamine (D2/D3) receptor binding and dopamine reactivity in the brain's reward pathway. To determine if compulsive tanners exhibited neurobiologic responses similar to other addictive disorders, this study assessed basal striatal D2/D3 binding and UVR-induced striatal dopamine efflux in ten addicted and ten infrequent tanners. In a double-blind crossover trial, UVR or sham UVR was administered in separate sessions during brain imaging with single photon emission computerized tomography (SPECT). Basal D2/D3 receptor density and UVR-induced dopamine efflux in the caudate were assessed using (123)I-iodobenzamide ((123)I-IBZM) binding potential non-displaceable (BPnd). Basal BPnd did not significantly differ between addicted and infrequent tanners. Whereas neither UVR nor sham UVR induced significant changes in bilateral caudate BPnd in either group, post-hoc analyses revealed left caudate BPnd significantly decreased (reflecting increased dopamine efflux) in the addicted tanners - but not the infrequent tanners - during the UVR session only. Bilateral ∆BPnd correlated with tanning severity only in the addicted tanners. These preliminary findings are consistent with a stronger neural rewarding response to UVR in addicted tanners, supporting a cutaneous-neural connection driving excessive sunbed use.
authors.affiliation: Department of Dermatology, University of Texas Southwestern, Dallas, TX, USA.
authors.forename: Pamela M
authors.initials: PM
authors.lastname: Aubert
authors.affiliation: Institute for Neurodegenerative Disorders, Molecular Neuroimaging, LLC, and Yale University, New Haven, MA, USA.
authors.forename: John P
authors.initials: JP
authors.lastname: Seibyl
authors.affiliation: Department of Psychiatry, University of Texas Southwestern, Dallas, TX, USA.
authors.forename: Julianne L
authors.initials: JL
authors.lastname: Price
authors.affiliation: Department of Neurology, University of Texas Southwestern, Dallas, TX, USA.
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Harris
authors.affiliation: Center for Brain Health, University of Texas Dallas, Dallas, TX, USA.
authors.forename: Francesca M
authors.initials: FM
authors.lastname: Filbey
authors.affiliation: Department of Dermatology, University of Texas Southwestern, Dallas, TX, USA.
authors.forename: Heidi
authors.initials: H
authors.lastname: Jacobe
authors.affiliation: Department of Neurology, University of Texas Southwestern, Dallas, TX, USA; Avid Radiopharmaceuticals, Inc, Philadelphia, PA, USA.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Devous
authors.affiliation: Department of Psychiatry, University of Texas Southwestern, Dallas, TX, USA; VA North Texas Health Care System, Dallas, TX, USA. Electronic address: bryon.adinoff@utsouthwestern.edu.
authors.forename: Bryon
authors.initials: B
authors.lastname: Adinoff
mesh_terms: D000328:Adult; D016739:Behavior, Addictive / Q000175:diagnosis / Q000378:metabolism* / Q000523:psychology*; D001921:Brain / Q000378:metabolism*; D003342:Corpus Striatum / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D017072:Neostriatum / Q000378:metabolism; D019275:Radiopharmaceuticals / Q000378:metabolism; D017448:Receptors, Dopamine D2 / Q000378:metabolism; D012201:Reward; D055108:Sunbathing / Q000523:psychology*; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D014466:Ultraviolet Rays / Q000009:adverse effects
chemical_list: D019275:Radiopharmaceuticals; D017448:Receptors, Dopamine D2; D004298:Dopamine
keywords: Addiction; Dopamine; Imaging; Mesostriatal reward system; SPECT; Tanning