Mou Xiang, Cheng Jingheng, Yu Yan S W, Kee Sara E, Ji Daoyun
Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, United States.
Department of Neuroscience, Baylor College of Medicine, Houston, TX, United States.
Front Cell Neurosci. 2018 Sep 21;12:332. doi: 10.3389/fncel.2018.00332. eCollection 2018.
Hippocampal place cells are key to spatial representation and spatial memory processing. They fire at specific locations in a space (place fields) and fire in precise patterns during theta sequences and during ripple-associated replay events. These phenomena have been extensively studied in rats, but to a less extent in mice. The availability of versatile genetic manipulations gives mice an advantage for place cell studies. However, it is unknown how place fields and place cell sequences in the same environment differ between mice and rats. Here, we provide a quantitative comparison in place field properties, as well as theta sequences and replays, between rats and mice as they ran on the same novel track and as they rested afterwards. We found that place cells in mice display less spatial specificity with more but smaller place fields. Theta oscillations, theta phase precession and aspects of theta sequences in mice are similar as those in rats. The ripple-associated replay, however, is relatively rare during stopping on the novel track in mice. The replay is present during resting after the track running, but is weaker in mice than the replay in rats. Our results suggest that place cells in mice and rats are qualitatively similar, but with substantial quantitative differences.
海马体位置细胞对于空间表征和空间记忆处理至关重要。它们在空间中的特定位置（位置野）放电，并在θ节律以及与涟漪相关的重放事件期间以精确模式放电。这些现象在大鼠中已得到广泛研究，但在小鼠中的研究程度较低。多种基因操作的可用性使小鼠在位置细胞研究方面具有优势。然而，尚不清楚在相同环境中，小鼠和大鼠的位置野及位置细胞序列有何不同。在此，我们对大鼠和小鼠在相同新跑道上奔跑以及随后休息时的位置野特性、θ节律和重放进行了定量比较。我们发现，小鼠的位置细胞表现出较低的空间特异性，具有更多但更小的位置野。小鼠的θ振荡、θ相位进动以及θ节律的某些方面与大鼠相似。然而，在小鼠于新跑道上停止时，与涟漪相关的重放相对较少。在跑完跑道后的休息期间会出现重放，但小鼠中的重放比大鼠中的弱。我们的结果表明，小鼠和大鼠的位置细胞在性质上相似，但存在显著的数量差异。
