Impact of morphometry, myelinization and synaptic current strength on spike conduction in human and cat spiral ganglion neurons.
Impact of morphometry, myelinization and synaptic current strength on spike conduction in human and cat spiral ganglion neurons.
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形态计量学，髓鞘化和突触电流强度对人和猫螺旋神经神经元的尖峰传导的影响。
DOI：
10.1371/journal.pone.0079256
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发表时间：
2013
期刊：
影响因子：
3.7
通讯作者：
Schrott-Fischer A
中科院分区：
文献类型：
--
作者：
Rattay F;Potrusil T;Wenger C;Wise AK;Glueckert R;Schrott-Fischer A
我们对听觉神经中神经编码的了解在很大程度上是基于对猫的实验。人和猫听觉神经元的解剖学差异可能导致锋电位传导速度和安全性的功能差异。共聚焦显微镜被用来系统地评估周围和中央过程的直径，髓鞘的共同性和螺旋神经节神经元（SGNs）的形态沿耳蜗的三个人和三只猫。基于这些形态学数据，模型分析揭示，在SGN的棘波传导的特点是由四个阶段：突触后延迟，恒定速度在外周过程中，体前延迟和恒定速度在中央过程。大多数SGN是I型，连接内毛细胞和脑干。与人类不同的是，猫的I型神经元完全是有髓鞘的。生物物理模型评价显示，由于缺乏髓鞘，在人类索马区域出现延迟和微弱的尖峰。模拟的棘波传导时间与人和猫听性脑干反应记录的正常波间潜伏期一致。模拟的内毛细胞带状突触的400 pA突触后电流是阈值的15倍以上。他们强制快速同步扣球。这两种特性都不存在于II型细胞中，因为它们接受更少和更弱的（1.26 pA）突触刺激。突触能量的浪费促进了锋电位的启动，从而保证了听觉信号时间精细结构的快速传递。然而，与猫神经元相比，人类I型神经元的索马区域中缺乏髓鞘导致尖峰传导的大延迟。缺乏髓鞘，结合较长的外周过程，导致定量差异的时间参数在电刺激人类耳蜗相比，猫耳蜗。
Our knowledge about the neural code in the auditory nerve is based to a large extent on experiments on cats. Several anatomical differences between auditory neurons in human and cat are expected to lead to functional differences in speed and safety of spike conduction. Confocal microscopy was used to systematically evaluate peripheral and central process diameters, commonness of myelination and morphology of spiral ganglion neurons (SGNs) along the cochlea of three human and three cats. Based on these morphometric data, model analysis reveales that spike conduction in SGNs is characterized by four phases: a postsynaptic delay, constant velocity in the peripheral process, a presomatic delay and constant velocity in the central process. The majority of SGNs are type I, connecting the inner hair cells with the brainstem. In contrast to those of humans, type I neurons of the cat are entirely myelinated. Biophysical model evaluation showed delayed and weak spikes in the human soma region as a consequence of a lack of myelin. The simulated spike conduction times are in accordance with normal interwave latencies from auditory brainstem response recordings from man and cat. Simulated 400 pA postsynaptic currents from inner hair cell ribbon synapses were 15 times above threshold. They enforced quick and synchronous spiking. Both of these properties were not present in type II cells as they receive fewer and much weaker (∼26 pA) synaptic stimuli. Wasting synaptic energy boosts spike initiation, which guarantees the rapid transmission of temporal fine structure of auditory signals. However, a lack of myelin in the soma regions of human type I neurons causes a large delay in spike conduction in comparison with cat neurons. The absent myelin, in combination with a longer peripheral process, causes quantitative differences of temporal parameters in the electrically stimulated human cochlea compared to the cat cochlea.
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影响因子：
2.5
作者：
BERGLUND, AM;RYUGO, DK
通讯作者：
RYUGO, DK
影响因子：
5.3
作者：
Hossain, WA;Antic, SD;Morest, DK
通讯作者：
Morest, DK
影响因子：
1.4
作者：
Liu, Wei;Bostrom, Marja;Rask-Andersen, Helge
通讯作者：
Rask-Andersen, Helge
DOI：
10.1044/jshr.1404.755
发表时间：
1971-01-01
期刊：
JOURNAL OF SPEECH AND HEARING RESEARCH
影响因子：
--
作者：
HOLLIEN, H;DEW, D;PHILIPS, P
通讯作者：
PHILIPS, P
影响因子：
5.5
作者：
HUXLEY, AF;STAMPFLI, R
通讯作者：
STAMPFLI, R