Vesicular dopamine release elicits an inhibitory postsynaptic current in midbrain dopamine neurons
Vesicular dopamine release elicits an inhibitory postsynaptic current in midbrain dopamine neurons
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DOI：
10.1016/j.neuron.2004.05.019
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发表时间：
2004-06-24
期刊：
影响因子：
16.2
通讯作者：
Williams, JT
中科院分区：
文献类型：
--
作者：
Beckstead, MJ;Grandy, DK;Williams, JT
多巴胺神经元的同步激活，例如在呈现意想不到的奖励刺激时，导致多巴胺从投射区和腹侧中脑内的体树突部位的两个末端释放。本文报道了多巴胺在小鼠中脑脑片上引起的抑制性突触后电流（IPSC）。IPSC是河豚毒素敏感的，钙依赖的，并被D2受体拮抗剂阻断。单胺转运体的抑制延长了IPSC，表明多巴胺神经传递的时间过程受到再摄取的严格调节。改变刺激强度改变的幅度，但不是IPSC的时间过程中，其发病速度比可以复制离子电渗。结果表明，多巴胺浓度在D2受体的快速上升，这表明，多巴胺是由一系列动作电位释放的作用在一个局部区域，而不是以符合体积传输的方式。
Synchronous activation of dopamine neurons, for instance upon presentation of an unexpected rewarding stimulus, results in the release of dopamine from both terminals in projection areas and somatodendritic sites within the ventral midbrain. This report describes an inhibitory postsynaptic current (IPSC) that was elicited by dopamine in slices from mouse midbrain. The IPSC was tetrodotoxin sensitive, calcium dependent, and blocked by a D2 receptor antagonist. Inhibition of monoamine transporters prolonged the IPSC, indicating that the time course of dopamine neurotransmission is tightly regulated by reuptake. Changing the stimulus intensity altered the amplitude but not the time course of the IPSC, whose onset was faster than could be reproduced with iontophoresis. The results indicate a rapid rise in dopamine concentration at the D2 receptors, suggesting that dopamine that is released by a train of action potentials acts in a localized area rather than in a manner consistent with volume transmission.