NMDA Receptor-Dependent Dynamics of Hippocampal Place Cell Ensembles
NMDA Receptor-Dependent Dynamics of Hippocampal Place Cell Ensembles
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DOI：
10.1523/jneurosci.0243-19.2019
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发表时间：
2019-06-26
影响因子：
5.3
通讯作者：
Hayashi, Yuichiro
中科院分区：
文献类型：
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作者：
Hayashi, Yuichiro
海马体是编码和存储记忆的关键大脑区域。当受试者处于环境中的特定位置时，海马位置细胞会通过放电来编码动物在空间中的位置。因此，位置细胞被认为对于空间记忆和导航至关重要。最近的研究表明，即使在熟悉的环境中，位置细胞的活动也不是恒定的，而是随着时间的推移而动态变化。然而，这些活性变化背后的机制尚未完全了解。在这项研究中，在虚拟现实环境中重复执行空间任务期间，追踪了雄性小鼠海马 CA1 神经元的活动。通过比较任务重复执行中的位置细胞集合表示，发现活动位置细胞群体的重叠率与时间相关，但与固定时间内的任务数量无关。这些发现表明，地点代码会自动且以恒定的速度变化。此外，还发现 NMDA 受体拮抗剂可抑制位置细胞活动的动态。总之，位置细胞活动的自发动态性质至少部分受到 NMDA 受体的调节，并且动态可能编码发作的时间信息。
The hippocampus is a key brain area to encoding and storing memories. Hippocampal place cells encode the position of an animal in space by firing when the subject is at a specific location in the environment. Therefore, place cells are considered essential to spatial memory and navigation. It has recently been revealed that place-cell activity is not constant even in a familiar environment, but changes dynamically over time. However, the mechanism behind these changes in activity is not yet fully understood. In this study, the activity of hippocampal CA1 neurons of male mice was tracked during repeated performances of a spatial task in a virtual reality environment. By comparing place-cell ensemble representations among repeated performance of the task, the overlap rate of the active place-cell population was found to be time dependent but independent of the number of tasks within a fixed time. These findings suggest that place codes change automatically and at a constant speed. Furthermore, the dynamics of place-cell activity were found to be suppressed by an NMDA receptor antagonist. In summary, the spontaneously dynamic nature of place-cell activity is at least in part regulated by NMDA receptors, and the dynamics may encode temporal information of episodes.