Dopamine (DA) transmission is important in the regulation of mood and anxiety behaviors. However, how specific dopaminergic signaling pathways respond to anxiogenic stimuli as well as regulate behaviors remains unknown. To understand how DA regulates the animal behaviors under anxiety we performed retrograde labeling and c-Fos staining of midbrain DA neurons. Our c-Fos labeling results showed that DA neurons projected to nucleus accumbens (NAc) are activated in animals treated with the elevated plus-maze (EPM). Real-time measurement of DA release using fast scanning cyclic voltammetry (FSCV) in NAc of freely behaving mice showed that increased DA release and more DA transients in the close arms than the open arms in the EPM. Meanwhile, we also observed a reduction of DA level from the close arms to the open arms. Local infusion of DA D₁ receptor antagonist, SCH23390 in the core of NAc, leads to an anxiolytic-like effect in the open-field and EPM. These anxiolytic effects were not observed in animals received D₂ receptor antagonist sulpiride infusion in the core of NAc. Taken together, our results reveal a novel function of the mesolimbic DA pathway through the D₁ receptor in the regulation of anxiety-like behaviors.

多巴胺 (DA) 传递在情绪和焦虑行为的调节中很重要。然而，具体的多巴胺能信号通路如何响应焦虑源刺激以及调节行为仍然未知。为了解 DA 如何调节焦虑下的动物行为，我们对中脑 DA 神经元进行了逆行标记和 c-Fos 染色。我们的 c-Fos 标记结果表明，投射到伏隔核 (NAc) 的多巴胺神经元在接受高架十字迷宫 (EPM) 处理的动物中被激活。在自由行为小鼠的 NAc 中使用快速扫描循环伏安法 (FSCV) 实时测量 DA 释放表明，与 EPM 中的张开臂相比，闭合臂中的 DA 释放增加和 DA 瞬变更多。同时，我们还观察到 DA 水平从闭臂到张开臂有所降低。局部输注DA D_{NAc 核心中的1}受体拮抗剂 SCH23390 在开放场和 EPM 中产生抗焦虑样作用。_{在接受 D 2}受体拮抗剂舒必利输注 NAc 核心的动物中未观察到这些抗焦虑作用。综上所述，我们的结果揭示了中脑边缘 DA 通路通过 D ₁受体调节焦虑样行为的新功能。