Pappata S, Dehaene S, Poline J B, Gregoire M C, Jobert A, Delforge J, Frouin V, Bottlaender M, Dolle F, Di Giamberardino L, Syrota A
INSERM U334, Service Hospitalier Frédéric Joliot, 4 Place du Géneral Leclerc, 91401, Orsay, France.
Neuroimage. 2002 Aug;16(4):1015-27. doi: 10.1006/nimg.2002.1121.
A new simple method is proposed to detect, using PET and [(11)C]raclopride, changes in striatal extracellular dopamine concentration during a rewarded effortful task. This approach aimed to increase the sensitivity in detection of these effects. It requires a single-dynamic PET study and combines the classic kinetic compartmental model with the general linear model of SPM to provide statistical inference on changes in [(11)C]raclopride time-activity curve due to endogenous dopamine release during two short periods of activation. Kinetic simulations predicted that 100% dopamine increase during two 5-min periods starting at 30 and 60 min after the injection can be detected. Moreover the effects of dopamine release on the [(11)C]raclopride time-activity-curve are different from those induced by CBF increase. These simulated curves were used to construct the statistical linear model and to test voxel-by-voxel in healthy subjects the hypothesis that dopamine is released in the ventral striatum during periods of unexpected monetary gains, but not during periods of unexpected monetary loss. The experimental results are in line with the expected results although the amplitude of the effects due to dopamine release is moderate. The advantages and the limits of this method as well as the relevance of the results for dopamine involvement in reward processing are discussed.
本文提出了一种新的简单方法，利用正电子发射断层扫描（PET）和[¹¹C]雷氯必利来检测在一项有奖励的费力任务期间纹状体细胞外多巴胺浓度的变化。该方法旨在提高检测这些效应的灵敏度。它需要进行一次动态PET研究，并将经典的动力学房室模型与统计参数映射（SPM）的一般线性模型相结合，以对由于内源性多巴胺在两个短激活期释放而导致的[¹¹C]雷氯必利时间-活性曲线变化提供统计推断。动力学模拟预测，在注射后30分钟和60分钟开始的两个5分钟时间段内多巴胺增加100%是可以检测到的。此外，多巴胺释放对[¹¹C]雷氯必利时间-活性曲线的影响与脑血流量增加所诱导的影响不同。这些模拟曲线被用于构建统计线性模型，并在健康受试者中逐体素检验以下假设：在意外金钱收益期间腹侧纹状体会释放多巴胺，而在意外金钱损失期间则不会。尽管多巴胺释放所导致的效应幅度适中，但实验结果与预期结果一致。本文还讨论了该方法的优点和局限性，以及这些结果对于多巴胺参与奖励处理的相关性。
