Evidence from Motoneurone Synchronization for Disynaptic Pathways in the Control of Inspiratory Motoneurones in the Cat
Evidence from Motoneurone Synchronization for Disynaptic Pathways in the Control of Inspiratory Motoneurones in the Cat
复制标题
来自运动神经元同步用于控制猫吸气运动神经元的突触通路的证据
DOI：
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发表时间：
1997
期刊：
影响因子：
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通讯作者：
P. A. Kirkwood
中科院分区：
文献类型：
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作者：
Christopher W. Vaughan;P. A. Kirkwood
1在麻醉、瘫痪的猫中，通过肋间神经或其肌内分支（T3至T8）或膈神经（C5根或C5和C6根独立）中成对吸气放电之间的交叉相关来测量运动神经元同步性。2所有互相关直方图均显示中心峰，相邻节段内的内部神经对的半幅（半宽）持续时间均小于相邻节段或节段内的外部神经对（平均值，1.6 ms vs.相邻节段的3.4 ms）。外部-内部对的值涵盖了这两个值的范围。最低值来自两对膈神经（1.2和1.4 ms）。（3）同节段的外-内对的峰通常是不对称的，峰的最大值往往被移位到约-1ms的滞后（外神经提供参考峰），而外-外对的峰总是对称的，以零为中心。膈内峰给出了最大的滞后约1毫秒小于膈外峰从相同的段。[4]对于持续时间和时间上的差异，有两种解释被认为是可能的：在通往外部神经运动神经元的通路上存在额外的突触，或者与外部神经运动神经元的单突触连接的相关核，其时间过程比内部或膈神经运动神经元的时间过程慢。计算机模拟，假设额外的突触，给出了一个很好的拟合所观察到的时间过程中的相关峰的所有类别的神经对使用单一值的参数（例如EPSP上升时间）与文献中的一致。这不能用不同的相关核模型来实现。高频振荡（HFO）的时间，有时存在于相关性中，也可以用突触外模型更好地预测。[5]我们的结论是，外部神经运动神经元之间的大多数同步来自双突触共同输入，任何半宽大于约2.2 ms的运动神经元同步峰都应该被认为可能包含双突触或寡突触衍生的成分。
1 Motoneurone synchronization was measured by cross‐correlation between paired inspiratory discharges in external and internal intercostal nerves or their intramuscular branches (T3 to T8) or in the phrenic nerve (C5 root or both C5 and C6 roots independently) in anaesthetized, paralysed cats. 2 All cross‐correlation histograms showed central peaks, for which the durations at half‐amplitude (half‐widths) from internal nerve pairs in adjacent segments were all less than for external nerve pairs in adjacent segments or within a segment (means, 1.6 ms vs. 3.4 ms for adjacent segments). Values for external‐internal pairs covered the ranges for both these two. Lowest values came from two phrenic pairs (1.2 and 1.4 ms). 3 The peaks from ipsisegmental external–internal pairs were usually asymmetric and the maximum of the peak was often displaced to a lag of about –1 ms (external nerve providing the reference spikes), whereas peaks from external–external pairs were always symmetrical and centred on zero. Phrenic–internal peaks gave maxima with lags about 1 ms less than for phrenic–external peaks from the same segments. 4 Two explanations were considered possible for the differences in duration and timing: an extra synapse on the pathway to the external nerve motoneurones, or a correlation kernel for a monosynaptic connection to the external nerve motoneurones that had a slower time course than that for the internal or phrenic nerve motoneurones. Computer simulations, assuming the extra synapse, gave a good fit to the observed time courses of the correlation peaks for all categories of nerve pairs using single values of parameters (e.g. EPSP rise time) consistent with those in the literature. This could not be achieved with the different correlation kernel model. The timing of high‐frequency oscillation (HFO), which was sometimes present in the correlations, was also better predicted with the extra synapse model. 5 It is concluded that most of the synchronization between external nerve motoneurones is derived from disynaptic common inputs and that any motoneurone synchronization peak with a half‐width greater than about 2.2 ms should be assumed to be likely to contain di‐ or oligosynaptically derived components.
DOI：
10.1152/jappl.1991.70.4.1447
发表时间：
1991
期刊：
Journal of applied physiology (Bethesda, Md. : 1985)
影响因子：
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作者：
DeTroyer,A
通讯作者：
DeTroyer,A
影响因子：
5.5
作者：
KIRKWOOD, PA;MUNSON, JB;WESTGAARD, RH
通讯作者：
WESTGAARD, RH