Time constants of h current in layer ii stellate cells differ along the dorsal to ventral axis of medial entorhinal cortex.
Time constants of h current in layer ii stellate cells differ along the dorsal to ventral axis of medial entorhinal cortex.
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DOI：
10.1523/jneurosci.3196-08.2008
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发表时间：
2008-09-17
期刊：
影响因子：
--
通讯作者：
Hasselmo ME
中科院分区：
文献类型：
--
作者：
Giocomo LM;Hasselmo ME
在行为正常的大鼠内侧内嗅皮层的慢性记录中发现了网格细胞，当大鼠处于六边形位置阵列时，神经元会被激活。在不同背腹解剖位置记录的网格细胞显示放电野大小和间距的系统变化。为了测试这些差异背后的可能机制，我们分析了电压钳记录中来自不同背腹位置的内嗅切片中星状细胞的超极化激活阳离子电流I（h）的特性。背、腹侧神经元h电流的时间常数有显著差异。在同一神经元中，电流的时间常数与膜电位振荡频率和弛豫电位的时间常数相关。电流的差异可能是膜电位振荡特性差异的基础，并有助于沿着内侧内嗅皮层背腹轴的网格细胞周期性。
Chronic recordings in the medial entorhinal cortex of behaving rats have found grid cells, neurons that fire when the rat is in a hexagonal array of locations. Grid cells recorded at different dorsal-ventral anatomical positions show systematic changes in size and spacing of firing fields. To test possible mechanisms underlying these differences, we analyzed properties of the hyperpolarization activated cation current I(h) in voltage clamp recordings from stellate cells in entorhinal slices from different dorsal-ventral locations. The time constant of h-current was significantly different between dorsal and ventral neurons. The time constant of h-current correlated with membrane potential oscillation frequency and the time constant of the sag potential in the same neurons. Differences in h-current could underlie differences in membrane potential oscillation properties and contribute to grid cell periodicity along the dorsal-ventral axis of medial entorhinal cortex.