Morphological and electrophysiological characteristics of layer V neurons of the rat lateral entorhinal cortex
Morphological and electrophysiological characteristics of layer V neurons of the rat lateral entorhinal cortex
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DOI：
10.1002/cne.10335
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发表时间：
2002-09-09
影响因子：
2.5
通讯作者：
Alonso, AA
中科院分区：
文献类型：
--
作者：
Hamam, BN;Amaral, DG;Alonso, AA
采用尖电极细胞内记录和生物胞素标记技术，研究了体外培养的外侧内嗅区（莱亚）V层神经元的电生理特性和形态学特征。形态学分析表明，莱亚的第V层包含三个不同的亚型的主要神经元，这被归类为锥体，水平，和多态神经元。锥体细胞是最丰富的亚型（57%），并可进一步细分为大，小和星形胞体的神经元。与锥体细胞相似，水平神经元（11%）具有突出的顶树突。然而，其独特的基底树突丛主要在水平面上延伸。多态性神经元（32%）的特点是多极树突状组织。在这三个类别的神经元的电生理分析表明，在每个类别内的电生理曲线的多样性和组之间没有显着差异。三个亚群的神经元均表现出瞬时和/或时间依赖性的内向整流和不同程度的锋电位频率适应。没有一个记录的细胞显示出内在的振荡爆发放电。然而，三个亚组中的许多神经元显示缓慢（3.5-14 Hz），持续的阈下膜电位振荡。在莱亚的主要神经元的形态和电生理多样性的平行，以前报道的内侧内嗅区，并建议，相对于深层，类似的信息处理进行跨内嗅皮层的中外侧范围。内嗅皮层的第五层可能承担非常复杂的操作，而不仅仅是充当海马处理信息到新皮层的中继站。
The intrinsic electrophysiological and morphological properties of lateral entorhinal area (LEA) layer V neurons were investigated by sharp electrode intracellular recording and biocytin labeling in vitro. The morphological analysis revealed that layer V of the LEA contains three distinct subtypes of principal neurons, which were classified as pyramidal, horizontal, and polymorphic neurons. Pyramidal cells were the most abundant subtype (57%) and could be further subdivided into neurons with large, small, and star-like somas. Similarly to pyramidal cells, horizontal neurons (11%) had a prominent apical dendrite. However, their distinctive basal dendritic plexus extended primarily in the horizontal plane. Polymorphic neurons (32%) were characterized by a multipolar dendritic organization. Electrophysiological analysis of neurons in the three categories demonstrated a diversity of electrophysiological profiles within each category and no significant differences between groups. Neurons in the three subgroups could display instantaneous and/or time-dependent inward rectification and different degrees of spike frequency adaptation. None of the recorded cells displayed an intrinsic oscillatory bursting discharge. Many neurons in the three subgroups, however, displayed slow (3.5-14 Hz), sustained, subthreshold membrane potential oscillations. The morphological and electrophysiological diversity of principal neurons in the LEA parallels that previously reported for the medial entorhinal area and suggests that, with respect to the deep layers, similar information processing is performed across the mediolateral extent of the entorhinal cortex. Layer V of the entorhinal cortex may undertake very complex operations beyond acting as a relay station of hippocampal processed information to the neocortex.