Steeves T D L, Miyasaki J, Zurowski M, Lang A E, Pellecchia G, Van Eimeren T, Rusjan P, Houle S, Strafella A P
Movement Disorders Centre, Toronto Western Hospital, UHN, Ontario, Canada.
Brain. 2009 May;132(Pt 5):1376-85. doi: 10.1093/brain/awp054. Epub 2009 Apr 3.
Pathological gambling is an impulse control disorder reported in association with dopamine agonists used to treat Parkinson's disease. Although impulse control disorders are conceptualized as lying within the spectrum of addictions, little neurobiological evidence exists to support this belief. Functional imaging studies have consistently demonstrated abnormalities of dopaminergic function in patients with drug addictions, but to date no study has specifically evaluated dopaminergic function in Parkinson's disease patients with impulse control disorders. We describe results of a [(11)C] raclopride positron emission tomography (PET) study comparing dopaminergic function during gambling in Parkinson's disease patients, with and without pathological gambling, following dopamine agonists. Patients with pathological gambling demonstrated greater decreases in binding potential in the ventral striatum during gambling (13.9%) than control patients (8.1%), likely reflecting greater dopaminergic release. Ventral striatal bindings at baseline during control task were also lower in patients with pathological gambling. Although prior imaging studies suggest that abnormality in dopaminergic binding and dopamine release may be markers of vulnerability to addiction, this study presents the first evidence of these phenomena in pathological gambling. The emergence of pathological gambling in a number of Parkinson's disease patients may provide a model into the pathophysiology of this disorder.
病理性赌博是一种冲动控制障碍，据报道与用于治疗帕金森病的多巴胺激动剂有关。尽管冲动控制障碍被概念化为成瘾谱系的一部分，但几乎没有神经生物学证据支持这一观点。功能成像研究一直表明药物成瘾患者存在多巴胺能功能异常，但迄今为止，尚无研究专门评估患有冲动控制障碍的帕金森病患者的多巴胺能功能。我们描述了一项[（11）C]雷氯必利正电子发射断层扫描（PET）研究的结果，该研究比较了服用多巴胺激动剂后，有和没有病理性赌博的帕金森病患者在赌博期间的多巴胺能功能。与对照患者（8.1%）相比，病理性赌博患者在赌博期间腹侧纹状体的结合潜能下降幅度更大（13.9%），这可能反映了多巴胺能释放增加。病理性赌博患者在对照任务期间基线时的腹侧纹状体结合也较低。尽管先前的成像研究表明多巴胺能结合和多巴胺释放异常可能是成瘾易感性的标志物，但本研究首次提供了这些现象在病理性赌博中的证据。一些帕金森病患者中病理性赌博的出现可能为这种疾病的病理生理学提供一个模型。
