Nucleus accumbens core (NAcc) has been implicated in impulsive choice, as measured in delay discounting. The role of dopamine (DA) in impulsive choice has received considerable attention, whereas glutamate (Glu) has recently been shown to be an important mediator of discounting. However, research has not examined how DA or Glu receptors in NAcc mediate different aspects of delay discounting performance, that is, (a) sensitivity to reinforcer magnitude and (b) sensitivity to delayed reinforcement. Adult male Sprague-Dawley rats were first trained in a delay discounting task, in which the delay to a large magnitude food reinforcer increased across blocks of trials. Following behavioral training, rats received bilateral implantation of guide cannulas into NAcc. Half of the rats (n = 12) received infusions of the DA-selective ligands SKF 38393 (D1-like agonist: 0.03 or 0.1 μg), SCH 23390 (D1-like antagonist: 0.3 or 1.0 μg), quinpirole (D2-like agonist: 0.3 or 1.0 μg), and eticlopride (D2-like antagonist: 0.3 or 1.0 μg). The other half received infusions of the ionotropic Glu ligands MK-801 (NMDA uncompetitive antagonist: 0.3 or 1.0 μg), AP-5 (NMDA competitive antagonist: 0.3 or 1.0 μg), ifenprodil (noncompetitive antagonist at NR2B-containing NMDA receptors: 0.3 or 1.0 μg), and CNQX (AMPA competitive antagonist: 0.2 or 0.5 μg). Results showed that SCH 23390 (0.3 μg) decreased sensitivity to reinforcer magnitude without altering impulsive choice, whereas ifenprodil (1.0 μg) decreased sensitivity to delayed reinforcement (i.e., impulsive choice). The current results show that DA and NMDA receptors in NAcc mediate distinct aspects of discounting performance. (PsycINFO Database Record

中文翻译：

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腔内给药多巴胺和离子型谷氨酸受体药物对大鼠延迟贴现性能的影响。

伏隔核（NAcc）已被包含在冲动选择中，以延迟贴现法衡量。多巴胺（DA）在冲动选择中的作用已受到相当多的关注，而最近发现谷氨酸（Glu）是打折的重要介体。但是，研究尚未检查NAcc中的DA或Glu受体如何介导延迟贴现性能的不同方面，即（a）对增强剂强度的敏感性和（b）对延迟增强的敏感性。成年雄性Sprague-Dawley大鼠首先接受了延迟贴现任务的训练，其中在较大规模的试验中，对食品强化剂的延迟增加。进行行为训练后，大鼠接受了将引导套管双侧植入NAcc。一半的大鼠（n = 12）接受DA选择性配体SKF 38393（D1类激动剂：0.03或0.1μg），SCH 23390（D1类拮抗剂：0.3或1.0μg），喹吡罗（D2类激动剂：0.3或1.0μg）和依替普利（D2样拮抗剂：0.3或1.0μg）。另一半接受离子型Glu配体MK-801（NMDA非竞争性拮抗剂：0.3或1.0μg），AP-5（NMDA竞争性拮抗剂：0.3或1.0μg），ifenprodil（含NR2B的NMDA受体的非竞争性拮抗剂）输注0.3或1.0μg）和CNQX（AMPA竞争性拮抗剂：0.2或0.5μg）。结果显示，SCH 23390（0.3μg）在不改变脉冲选择的情况下降低了对增强剂幅度的敏感性，而艾芬地尔（1.0μg）在延迟选择（即脉冲选择）下降低了对延迟增强的敏感性。目前的结果表明，NAcc中的DA和NMDA受体介导了贴现性能的不同方面。（PsycINFO数据库记录