Dopamine operates as a subsecond modulator of food seeking
Dopamine operates as a subsecond modulator of food seeking
复制标题
DOI：
10.1523/jneurosci.3823-03.2004
复制
发表时间：
2004-02-11
影响因子：
5.3
通讯作者：
Carelli, RM
中科院分区：
文献类型：
--
作者：
Roitman, MF;Stuber, GD;Carelli, RM
多巴胺投射到脑桥核与获得和消耗自然奖励的行为有关。建立这种联系的神经化学研究是在几分钟内进行时间平均测量的，因此多巴胺变化和这些行为之间的精确时间关系尚不清楚。为了解决这个问题，我们每隔100毫秒使用快速扫描循环伏安法在训练按下蔗糖杠杆的大鼠的延髓核中的碳纤维微电极上采样多巴胺。提示有机会对蔗糖诱发的多巴胺释放（67 +/- 20 nM）做出反应，潜伏期短（0.2 +/- 0.1秒开始）。当同样的提示被呈现给未接触过提示-蔗糖配对的大鼠时，没有观察到类似的多巴胺信号。因此，经过训练的大鼠中线索诱发的多巴胺增加反映了线索与蔗糖可用性之间的习得性关联。在多巴胺激增的高峰期发生了对蔗糖的杠杆压力。在杠杆按压后，当蔗糖被输送和消耗时，没有检测到多巴胺的进一步增加。相反，多巴胺恢复到基线水平。总之，这些结果强烈暗示了丘脑核中的亚秒多巴胺信号是觅食行为的实时调节剂。
The dopamine projection to the nucleus accumbens has been implicated in behaviors directed toward the acquisition and consumption of natural rewards. The neurochemical studies that established this link made time-averaged measurements over minutes, and so the precise temporal relationship between dopamine changes and these behaviors is not known. To resolve this, we sampled dopamine every 100 msec using fast-scan cyclic voltammetry at carbon-fiber microelectrodes in the nucleus accumbens of rats trained to press a lever for sucrose. Cues that signal the opportunity to respond for sucrose evoked dopamine release (67 +/- 20 nM) with short latency (0.2 +/- 0.1 sec onset). When the same cues were presented to rats naive to the cue - sucrose pairing, similar dopamine signals were not observed. Thus, cue-evoked increases in dopamine in trained rats reflected a learned association between the cues and sucrose availability. Lever presses for sucrose occurred at the peak of the dopamine surges. After lever presses, and while sucrose was delivered and consumed, no further increases in dopamine were detected. Rather, dopamine returned to baseline levels. Together, the results strongly implicate subsecond dopamine signaling in the nucleus accumbens as a real-time modulator of food-seeking behavior.