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研究揭示奖励引起纹状体多巴胺释放的影响
作者:小柯机器人 发布时间:2020/4/2 20:44:04

美国麻省理工学院的Alan Jasanoff研究小组取得一项新进展,他们揭示了奖励引起纹状体多巴胺释放的局部和整体影响。该项研究成果于2020年4月1日在线发表在《自然》杂志上。

结合动态多巴胺敏感的分子成像和功能磁共振成像,研究人员确定了纹状体多巴胺释放如何塑造对大鼠大脑奖励性刺激的局部和整体反应。他们发现,多巴胺通过可量化的突触后效果(在各个亚区域之间有所不同),持续改变整个纹状体的刺激反应的持续时间,但不会改变其幅度。
 
纹状体多巴胺的释放还增强了远端反应的网络,研究人员使用了神经化学依赖性功能连接分析来描述。多巴胺能驱动的热点包括了与边缘和运动功能相关的皮质区域。
 
这些研究结果表明,纹状体多巴胺具有独特的神经调节作用,该作用远超出其峰值释放部位,并且可以增强远端神经群体的激活(执行主动行为所必需的)。这些发现还提示了多巴胺能功能的全脑生物标志物,并可能增加对学习和成瘾相关神经影像学结果的了解。
 
据介绍,神经递质多巴胺是通过奖励刺激来强化动作所需的。神经科学家试图以简明的概念性术语来定义多巴胺的功能,但是多巴胺释放的实际含义取决于其在全脑的不同后果。尽管多巴胺能信号的分子和细胞效应已被广泛研究,但对多巴胺对更大范围神经活动的影响却鲜为人知。
 
附:英文原文

Title: Local and global consequences of reward-evoked striatal dopamine release

Author: Nan Li, Alan Jasanoff

Issue&Volume: 2020-04-01

Abstract: The neurotransmitter dopamine is required for the reinforcement of actions by rewarding stimuli1. Neuroscientists have tried to define the functions of dopamine in concise conceptual terms2, but the practical implications of dopamine release depend on its diverse brain-wide consequences. Although molecular and cellular effects of dopaminergic signalling have been extensively studied3, the effects of dopamine on larger-scale neural activity profiles are less well-understood. Here we combine dynamic dopamine-sensitive molecular imaging4 and functional magnetic resonance imaging to determine how striatal dopamine release shapes local and global responses to rewarding stimulation in rat brains. We find that dopamine consistently alters the duration, but not the magnitude, of stimulus responses across much of the striatum, via quantifiable postsynaptic effects that vary across subregions. Striatal dopamine release also potentiates a network of distal responses, which we delineate using neurochemically dependent functional connectivity analyses. Hot spots of dopaminergic drive notably include cortical regions that are associated with both limbic and motor function. Our results reveal distinct neuromodulatory actions of striatal dopamine that extend well beyond its sites of peak release, and that result in enhanced activation of remote neural populations necessary for the performance of motivated actions. Our findings also suggest brain-wide biomarkers of dopaminergic function and could provide a basis for the improved interpretation of neuroimaging results that are relevant to learning and addiction.

DOI: 10.1038/s41586-020-2158-3

Source: https://www.nature.com/articles/s41586-020-2158-3

期刊信息

Nature:《自然》,创刊于1869年。隶属于施普林格·自然出版集团,最新IF:43.07
官方网址:http://www.nature.com/
投稿链接:http://www.nature.com/authors/submit_manuscript.html