Biopsychological study on the role of brain glutamate receptors in learning and memory

尽管最近有人提出NMDA受体与记忆和学习有关，但关于NMDA受体在特定脑区的作用的行为学研究还很少。本研究采用径向迷宫学习任务和微量注射特定激动剂和拮抗剂的方法，研究了脑内NMDA受体在空间记忆中的作用。首先，我们检测了海马区微量注射竞争性和非竞争性NMDA受体拮抗剂(分别为AP5和MK-801)对大鼠在放射状迷宫中表现的影响。两者均显著影响大鼠的正确操作，而纹状体内注射AP5对放射状迷宫的操作没有影响，提示海马区的NMDA受体在空间记忆中起重要作用。我们测试了海马区注射甘氨酸受体激动剂dcs对由系统性MK-801引起的放射状迷宫任务的空间记忆缺陷的影响。DCs改善了MK-801所致的学习记忆障碍，提示甘氨酸通过对海马神经元NMDA受体的调节作用参与了空间记忆。

Although it has recently been suggested that NMDA receptors are associated with memory and learning, there has been only a few behavioral studies on the role of NMDA receptors in specific brain regions. In this study, using radial maze learning task and a microinjection technique of specific agonists and antagonists, we investigated the role of brain NMDA receptors in spatial memory.We first tested the effects of intrahippocampal microinjection of competitive and non-competitive NMDA receptor antagonists (AP5 and MK-801, respectively) on the rats' performance in radial maze. Both of them markedly impaired the correct performance while the AP5 treatment into the striatum did not have any effect on radial maze performance, suggesting that NMDA receptors in the hippocampus play an important role in spatial memory.NMDA receptors consist of several subcomponents. We tested the effects of intrahippocampal treatment of DCS, a glycine-site agonist, on spatial memory deficits in radial maze task produced by systemic MK-801. DCS improved the MK-801-induced performance impairment, suggesting that glycine sites are involved in spatial memory through their modulatory action on hippocampal NMDA receptors.