Role of nucleus accumbens dopamine D1 and D2 receptors in instrumental and Pavlovian paradigms of conditioned reward
Role of nucleus accumbens dopamine D1 and D2 receptors in instrumental and Pavlovian paradigms of conditioned reward
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DOI：
10.1007/s002130000505
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发表时间：
2000-09-01
影响因子：
3.4
通讯作者：
Schnitzler, HU
中科院分区：
文献类型：
--
作者：
Koch, M;Schmid, A;Schnitzler, HU
理由：本研究调查了伏核多巴胺 D-1 和 D-2 受体在两种不同的条件奖励范式中的作用。目的：我们解决了累积多巴胺对于运动或奖励的动机成分是否重要的问题。方法：我们比较了精囊内输注多巴胺 D-1 受体拮抗剂 SCH23390（0.3、1.0、3.0 μg）和 D-2 受体拮抗剂舒必利（0.3、1.0、3.0 μg）对条件性杠杆压取食物的影响，以及条件性奖赏信号对惊吓反应的抑制作用。结果：D-1 和 D-2 拮抗剂剂量依赖性地减弱了在固定响应比例下对奖赏的条件杠杆压力，并增加了免费实验室食物的消耗。然而，对可自由获得的颗粒的偏好，以及在预测奖励的条件刺激存在下的惊吓反应的减弱，并没有因伏藏多巴胺受体的阻断而受到损害。结论：我们的数据支持这样的观点，即伏隔核中的多巴胺对于奖励背景下的工具反应选择是必需的，而不仅仅是行为的运动表现或评估奖励刺激的享乐特性。
Rationale: This study investigated the role of nucleus accumbens dopamine D-1 and D-2 receptors in two different paradigms of conditioned reward. Objective: We addressed the question whether accumbal dopamine is important for the motor or for the motivational components of reward. Methods: We compared the effects of intra-accumbal infusion of the dopamine D-1 receptor antagonist SCH23390 (0.3, 1.0, 3.0 mu g) and the D-2 receptor antagonist sulpiride (0.3, 1.0, 3.0 mu g) on conditioned lever pressing for food, with the effects on the inhibition of the startle response by a conditioned reward signal. Results: Both the D-1 and the D-2 antagonist dose-dependently attenuated conditioned lever pressing for reward under a fixed-ratio of responding and increased the consumption of freely available lab chow. However, the preference for freely available pellets, and the attenuation of the startle response in the presence of a conditioned stimulus predicting reward were not impaired by blockade of accumbal dopamine receptors. Conclusions: Our data support the idea that dopamine in the nucleus accumbens is necessary for instrumental response selection in the context of reward rather than for the mere motor performance of behavior or for the evaluation of the hedonic properties of rewarding stimuli.