Axon initial segment geometry in relation to motoneuron excitability.
Axon initial segment geometry in relation to motoneuron excitability.
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DOI：
10.1371/journal.pone.0259918
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发表时间：
2021
期刊：
影响因子：
3.7
通讯作者：
Cope TC
中科院分区：
文献类型：
--
作者：
Rotterman TM;Carrasco DI;Housley SN;Nardelli P;Powers RK;Cope TC
负责动作电位起始的轴突起始段是一个随神经元兴奋性变化而变化的动态结构。与其他类型的神经元一样，哺乳动物脊髓中的α运动神经元在AIS几何上表现出异质性和可塑性，包括长度（AISl）和与躯体的距离（AISd）。本研究旨在建立AIS几何与固有兴奋性测量的关系，流变电流，在正常运动神经元中变化20倍或更多。我们首先确定运动池中表现出不同活动特征的运动神经元的AIS长度或距离是否不同。从内侧腓肠肌（MG）运动池取样的运动神经元显示出的平均AISd值明显大于比目鱼肌（SOL）运动神经元，后者更容易在低水平活动中被招募。接下来，我们测试了AISd是否与单个运动神经元的内在兴奋性共变。在麻醉大鼠中，我们测量了MG运动神经元在体内的细胞内流变酶电流，然后标记它们用于免疫组织化学研究AIS结构。对于从MG运动池取样的16个运动神经元，这种组合方法显示AISd，而不是AISl，与流变酶显著相关，因为AIS往往位于离体细胞较远的运动神经元上，这些运动神经元的兴奋性较低。尽管与兴奋性之间的因果关系似乎不太可能，但AISd属于与运动单元及其母运动神经元的招募性相关的一系列特性。
The axon initial segment (AIS) responsible for action potential initiation is a dynamic structure that varies and changes together with neuronal excitability. Like other neuron types, alpha motoneurons in the mammalian spinal cord express heterogeneity and plasticity in AIS geometry, including length (AISl) and distance from soma (AISd). The present study aimed to establish the relationship of AIS geometry with a measure of intrinsic excitability, rheobase current, that varies by 20-fold or more among normal motoneurons. We began by determining whether AIS length or distance differed for motoneurons in motor pools that exhibit different activity profiles. Motoneurons sampled from the medial gastrocnemius (MG) motor pool exhibited values for average AISd that were significantly greater than that for motoneurons from the soleus (SOL) motor pool, which is more readily recruited in low-level activities. Next, we tested whether AISd covaried with intrinsic excitability of individual motoneurons. In anesthetized rats, we measured rheobase current intracellularly from MG motoneurons in vivo before labeling them for immunohistochemical study of AIS structure. For 16 motoneurons sampled from the MG motor pool, this combinatory approach revealed that AISd, but not AISl, was significantly related to rheobase, as AIS tended to be located further from the soma on motoneurons that were less excitable. Although a causal relation with excitability seems unlikely, AISd falls among a constellation of properties related to the recruitability of motor units and their parent motoneurons.
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影响因子：
5.3
作者：
Höfflin F;Jack A;Riedel C;Mack-Bucher J;Roos J;Corcelli C;Schultz C;Wahle P;Engelhardt M
通讯作者：
Engelhardt M
DOI：
10.1111/j.2044-8317.2011.02037.x
发表时间：
2013-02
期刊：
The British journal of mathematical and statistical psychology
影响因子：
--
作者：
Gelman A;Shalizi CR
通讯作者：
Shalizi CR
影响因子：
2
作者：
Gelman, Andrew
通讯作者：
Gelman, Andrew
影响因子：
5.3
作者：
Alshammari MA;Alshammari TK;Laezza F
通讯作者：
Laezza F
影响因子：
7.7
作者：
Goethals, Sarah;Brette, Romain
通讯作者：
Brette, Romain