Firing relations of medial entorhinal neurons to the hippocampal theta rhythm in urethane anesthetized and walking rats.
Firing relations of medial entorhinal neurons to the hippocampal theta rhythm in urethane anesthetized and walking rats.
复制标题
乌拉坦麻醉和行走大鼠内侧内嗅神经元与海马θ节律的放电关系。
DOI：
10.1007/bf00229252
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发表时间：
1992
影响因子：
2
通讯作者：
Fox,SE
中科院分区：
文献类型：
--
作者：
Stewart,M;Quirk,GJ;Barry,M;Fox,SE
在乌拉坦麻醉和步行的大鼠中，研究了内侧内嗅皮层（MEC）第II层和第III层神经元的放电与海马θ节律的关系。1)MEC神经元表现出显着的相位关系，海马θ节律在步行和氨基甲酸乙酯麻醉大鼠，这表明该地区有助于生成两个阿托品耐药和阿托品敏感的θ节律组件。2)与麻醉大鼠（8/23个细胞）相比，行走大鼠（22/23个细胞）中锁相细胞的比例大三倍，表明MEC细胞在行走θ节律期间做出更大的贡献。这种差异也表现在行走过程中锁相MEC细胞组的平均矢量长度更大：0.39 ± 0.13对0.21 ± 0.08。步行和尿烷条件之间的射击率差异不显着。3)在步行大鼠中，MEC细胞在齿状θ节律的正峰上放电（组平均相位= 5°; 0° =海马裂处的正峰）。这与齿状颗粒和海马锥体细胞的报告阶段接近。氨基甲酸乙酯麻醉大鼠MEC细胞时相的分布范围更广（组平均时相= 90°），与海马投射细胞的时相数据一致，这些发现表明内侧内嗅神经元是海马神经元θ相关放电的主要决定因素，与氨基甲酸乙酯麻醉相比，它们在行走中的稳健节律性导致了两种条件下的EEG差异。
The firing of neurons from layers II and III of medial entorhinal cortex (MEC) was examined in relation to the hippocampal theta rhythm in urethane anesthetized and walking rats. 1) MEC neurons showed a significant phase relation to the hippocampal theta rhythm in both walking and urethane anesthetized rats, suggesting that this region contributes to the generation of both atropine-resistant and atropine-sensitive theta rhythm components. 2) The proportion of phase-locked cells was three times greater in walking rats (22/23 cells) as compared to anesthetized rats (8/23 cells), indicating that MEC cells made a greater contribution during walking theta rhythm. This difference was also manifest in the greater mean vector length for the group of phase-locked MEC cells during walking: 0.39 ± 0.13 versus 0.21 ± 0.08. Firing rate differences between walking and urethane conditions were not significant. 3) In walking rats, MEC cells fired on the positive peak of the dentate theta rhythm (group mean phase = 5°; 0° = positive peak at the hippocampal fissure). This is close to the reported phases for dentate granule and hippocampal pyramidal cells. The distribution of MEC cell phases in urethane anesthetized rats was broader (group mean phase = 90°), consistent with the phase data reported for hippocampal projection cells.These findings suggest that medial entorhinal neurons are the principal determinant of theta-related firing of hippocampal neurons and that their robust rhythmicity in walking as compared to urethane anesthesia accounts for EEG differences across the two conditions.