Quantitative morphometry of electrophysiologically identified CA3b interneurons reveals robust local geometry and distinct cell classes.
Quantitative morphometry of electrophysiologically identified CA3b interneurons reveals robust local geometry and distinct cell classes.
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DOI：
10.1002/cne.22082
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发表时间：
2009-08-20
期刊：
影响因子：
--
通讯作者：
Barrionuevo G
中科院分区：
文献类型：
--
作者：
Ascoli GA;Brown KM;Calixto E;Card JP;Galván EJ;Perez-Rosello T;Barrionuevo G
海马CA 3区抑制性细胞的形态和电生理多样性可能是特定计算角色的基础，尚未完全阐明。特别是，放射层（R）和陷窝-分子层（L-M）中具有胞体的中间神经元接收来自齿状回和内嗅皮层以及CA 3内的会聚刺激。虽然这些细胞表达不同形式的突触可塑性，但它们的轴突树和连接性在很大程度上仍然是未知的。我们研究了分支和空间模式，再加上膜和突触特性，大鼠CA 3b R和L-M中间神经元数字化重建后，细胞内标记。我们发现相当大的变化，但两层之间没有差异，形态和生物物理特性之间没有相关性。然而，两种细胞类型的树突分叉的数量的基础上确定，具有显着不同的解剖和电生理特征。轴突的分支一般比树突多一个数量级。然而，在R/L-M边界两侧的中间神经元显示出令人惊讶的模块化轴-树突分支，具有一致的均匀局部分支几何形状。轴突和树突都遵循层状组织，轴突表现出对裂缝的空间偏好。此外，只有一小部分轴突轴杆延伸到侵入体积的外部，并倾向于返回到近端区域。相比之下，树突状树表现出更有限的，但各向同性的体积占用。这些结果表明，R和L-M中间神经元主要是局部前馈和侧抑制控制的作用。这种作用可能是必不可少的，以平衡广泛的经常性兴奋的CA 3区海马自联想记忆功能。
The morphological and electrophysiological diversity of inhibitory cells in hippocampal area CA3 may underlie specific computational roles and is not yet fully elucidated. In particular, interneurons with somata in strata radiatum (R) and lacunosum-moleculare (L-M) receive converging stimulation from the dentate gyrus and entorhinal cortex as well as within CA3. Although these cells express different forms of synaptic plasticity, their axonal trees and connectivity are still largely unknown. We investigated the branching and spatial patterns, plus the membrane and synaptic properties, of rat CA3b R and L-M interneurons digitally reconstructed after intracellular labeling. We found considerable variability within but no difference between the two layers, and no correlation between morphological and biophysical properties. Nevertheless, two cell types were identified based on the number of dendritic bifurcations, with significantly different anatomical and electrophysiological features. Axons generally branched an order of magnitude more than dendrites. However, interneurons on both sides of the R/L-M boundary revealed surprisingly modular axo-dendritic arborizations with consistently uniform local branch geometry. Both axons and dendrites followed a lamellar organization, and axons displayed a spatial preference towards the fissure. Moreover, only a small fraction of the axonal arbor extended to the outer portion of the invaded volume, and tended to return towards the proximal region. In contrast, dendritic trees demonstrated more limited but isotropic volume occupancy. These results suggest a role of predominantly local feedforward and lateral inhibitory control for both R and L-M interneurons. Such role may be essential to balance the extensive recurrent excitation of area CA3 underlying hippocampal autoassociative memory function.
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影响因子：
3.5
作者：
BERNARD, C;WHEAL, HV
通讯作者：
WHEAL, HV
影响因子：
2.5
作者：
Chitwood, RA;Jaffe, DB
通讯作者：
Jaffe, DB
DOI：
10.1016/s0165-3806(01)00130-4
发表时间：
2001-04-30
期刊：
DEVELOPMENTAL BRAIN RESEARCH
影响因子：
--
作者：
Gaïarsa, JL;Khalilov, I;Ben-Ari, Y
通讯作者：
Ben-Ari, Y
影响因子：
2.9
作者：
Andersen, P;Soleng, AF;Raastad, M
通讯作者：
Raastad, M
影响因子：
5.5
作者：
Blatow, M;Caputi, A;Monyer, H
通讯作者：
Monyer, H