Université de Bordeaux, Institut des Maladies Neurodégénératives, Unité Mixte de Recherche 5293, Bordeaux F-33000, France.
Centre National de la Recherche Scientifique, Institut des Maladies Neurodégénératives, Unité Mixte de Recherche 5293, Bordeaux F-33000, France.
eNeuro. 2020 May 20;7(3). doi: 10.1523/ENEURO.0081-20.2020. Print 2020 May/Jun.
Dopamine (DA) plays a crucial role in the control of motor and higher cognitive functions such as learning, working memory, and decision making. The primary motor cortex (M1), which is essential for motor control and the acquisition of motor skills, receives dopaminergic inputs in its superficial and deep layers from the midbrain. However, the precise action of DA and DA receptor subtypes on the cortical microcircuits of M1 remains poorly understood. The aim of this work was to investigate in mice how DA, through the activation of D2-like receptors (D2Rs), modulates the cellular and synaptic activity of M1 parvalbumin-expressing interneurons (PVINs) which are crucial to regulate the spike output of pyramidal neurons (PNs). By combining immunofluorescence, electrophysiology, pharmacology and optogenetics approaches, we show that D2R activation increases neuronal excitability of PVINs and GABAergic synaptic transmission between PVINs and PNs in Layer V of M1. Our data reveal how cortical DA modulates M1 microcircuitry, which could be important in the acquisition of motor skills.
多巴胺（DA）在运动和高级认知功能（如学习、工作记忆和决策）的控制中起着至关重要的作用。主要运动皮层（M1）对于运动控制和运动技能的获得至关重要，从中脑的浅层和深层接收多巴胺能输入。然而，DA 和 DA 受体亚型对 M1 皮质微电路的确切作用仍知之甚少。这项工作的目的是在小鼠中研究 DA 通过激活 D2 样受体（D2Rs）如何调节 M1 表达 parvalbumin 的中间神经元（PVINs）的细胞和突触活动，这对于调节锥体神经元（PNs）的尖峰输出至关重要。通过结合免疫荧光、电生理学、药理学和光遗传学方法，我们表明 D2R 激活增加了 M1 第 V 层中 PVINs 的神经元兴奋性和 PVINs 与 PNs 之间的 GABA 能突触传递。我们的数据揭示了皮质 DA 如何调节 M1 微电路，这对于运动技能的获得可能很重要。
