Cooperativity between remote sites of ectopic spiking allows afterdischarge to be initiated and maintained at different locations.
Cooperativity between remote sites of ectopic spiking allows afterdischarge to be initiated and maintained at different locations.
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DOI：
10.1007/s10827-015-0562-8
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发表时间：
2015-08
影响因子：
1.2
通讯作者：
Prescott, Steven A.
中科院分区：
文献类型：
--
作者：
Coggan, Jay S.;Sejnowski, Terrence J.;Prescott, Steven A.
神经损伤的许多症状是由过度兴奋引起的异位尖峰引起的。异位尖峰可以起源于轴突损伤部位和受影响神经元内的其他部位。这就提出了一个问题：局部损伤是否会引起细胞范围内的兴奋性变化和/或兴奋性的局部变化是否会导致远程位置的异常尖峰。计算机建模揭示了后者的一个例子，涉及后放电（AD）刺激诱发的尖峰，持续时间超过刺激。我们发现，AD起源于轴突的一个过度兴奋的区域可以转移到索马，在那里它被维持。异位峰起始的这种重新定位与两个位点之间的距离无关，但依赖于起源于第一个位点的异位峰的速率和数量。一个简化模型的非线性动力学分析表明，属性，使轴突网站倾向于启动AD劝阻它保持AD，而索马有相反的属性，从而使两个网站相互合作。起源于轴突的AD的第一阶段可以通过提供足够的驱动来触发体细胞AD，让位于起源于索马的AD的第二阶段，使得当轴突AD失败时尖峰继续。异位棘波起源于索马在第2阶段AD传播成功通过轴突棘波起始的失效网站。这种新的机制，即在一个部位的异位尖峰促进在另一个部位的异位尖峰可能有助于慢性化的过度兴奋的条件，如神经性疼痛。
Many symptoms of nerve damage arise from ectopic spiking caused by hyperexcitability. Ectopic spiking can originate at the site of axonal damage and elsewhere within affected neurons. This raises the question of whether localized damage elicits cell-wide changes in excitability and/or if localized changes in excitability can drive abnormal spiking at remote locations. Computer modeling revealed an example of the latter involving afterdischarge (AD) – stimulus-evoked spiking that outlasts stimulation. We found that AD originating in a hyperexcitable region of axon could shift to the soma where it was maintained. This repositioning of ectopic spike initiation was independent of distance between the two sites but relied on the rate and number of ectopic spikes originating from the first site. Nonlinear dynamical analysis of a reduced model demonstrated that properties which rendered the axonal site prone to initiating AD discouraged it from maintaining AD, whereas the soma had the inverse properties thus enabling the two sites to interact cooperatively. A first phase of AD originating in the axon could, by providing sufficient drive to trigger somatic AD, give way to a second phase of AD originating in the soma such that spiking continued when axonal AD failed. Ectopic spikes originating from the soma during phase 2 AD propagated successfully through the defunct site of axonal spike initiation. This novel mechanism whereby ectopic spiking at one site facilitates ectopic spiking at another site is likely to contribute to the chronification of hyperexcitability in conditions such as neuropathic pain.
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影响因子：
3.5
作者：
Ho, Cojen;O'Leary, Michael E.
通讯作者：
O'Leary, Michael E.
影响因子：
7
作者：
Hammer, Paul;Banck, Michaela S.;Beutler, Andreas S.
通讯作者：
Beutler, Andreas S.
DOI：
10.1073/pnas.1013798107
发表时间：
2010-11-30
影响因子：
11.1
作者：
Coggan, Jay S.;Prescott, Steven A.;Sejnowski, Terrence J.
通讯作者：
Sejnowski, Terrence J.
影响因子：
14.5
作者：
Kapoor, R;Li, YG;Smith, KJ
通讯作者：
Smith, KJ
影响因子：
14.5
作者：
Louter, Mark A.;Bosker, Johanneke E.;Terwindt, Gisela M.
通讯作者：
Terwindt, Gisela M.