Aizman O, Brismar H, Uhlén P, Zettergren E, Levey A I, Forssberg H, Greengard P, Aperia A
Department of Woman and Child Health, Karolinska Institutet, Astrid Lindgren Children's Hospital, Q2:09, 171 76 Stockholm, Sweden.
Nat Neurosci. 2000 Mar;3(3):226-30. doi: 10.1038/72929.
Despite the importance of dopamine signaling, it remains unknown if the two major subclasses of dopamine receptors exist on the same or distinct populations of neurons. Here we used confocal microscopy to demonstrate that virtually all striatal neurons, both in vitro and in vivo, contained dopamine receptors of both classes. We also provide functional evidence for such colocalization: in essentially all neurons examined, fenoldopam, an agonist of the D1 subclass of receptors, inhibited both the Na+/K+ pump and tetrodotoxin (TTX)-sensitive sodium channels, and quinpirole, an agonist of the D2 subclass of receptors, activated TTX-sensitive sodium channels. Thus D1 and D2 classes of ligands may functionally interact in virtually all dopamine-responsive neurons within the basal ganglia.
尽管多巴胺信号传导很重要，但两种主要的多巴胺受体亚类是否存在于相同或不同的神经元群体中仍然未知。在这里，我们使用共聚焦显微镜来证明，几乎所有体外和体内的纹状体神经元都含有这两类多巴胺受体。我们还为这种共定位提供了功能证据：在基本上所有检测的神经元中，受体D1亚类的激动剂非诺多泮抑制了Na+/K+泵和河豚毒素（TTX）敏感的钠通道，而受体D2亚类的激动剂喹吡罗激活了TTX敏感的钠通道。因此，D1和D2类配体可能在基底神经节内几乎所有对多巴胺有反应的神经元中发生功能相互作用。
