Dynamics of intrinsic dendritic calcium signaling during tonic firing of thalamic reticular neurons.
Dynamics of intrinsic dendritic calcium signaling during tonic firing of thalamic reticular neurons.
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DOI：
10.1371/journal.pone.0072275
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发表时间：
2013
期刊：
影响因子：
3.7
通讯作者：
Lambert RC
中科院分区：
文献类型：
--
作者：
Chausson P;Leresche N;Lambert RC
丘脑网状核gaba能神经元控制丘脑和皮层之间的交流，不仅通过轴-树突突触，还通过间隙连接和树突-树突突触相互连接。目前尚不清楚这些树突通讯过程是否可能分别由网状核神经元在清醒和睡眠期间所显示的强直性和t型Ca2+通道依赖性的高频脉冲动作电位触发。事实上，虽然已知t型Ca2+通道的激活在整个树突树中积极传播，但仍不清楚强直动作电位放电是否也可以侵入树突树化。在这里，使用双光子显微镜，我们证明了树突Ca2+反应在模拟觉醒相关的强直放电的体诱发动作电位之后，在整个树突树突化过程中被检测到。钙内流暂时累积产生树突状Ca2+积累，这与动作电位序列的持续时间线性相关。增加放电频率有助于Ca2+在近端而不是远端树突室内的内流，这表明树突树突化在反向传播动作电位方面起着低通滤波器的作用。在树突树的更远的室室中，t型Ca2+通道在动作电位触发的Ca2+内流中起着至关重要的作用，这表明Ca2+内流可能由局部树突膜电位的轻微变化控制，从而决定t型通道的可用性。我们的结论是，通过介导整个树突化过程中的Ca2+动态，丘脑网状核神经元的强直和突发放电可能控制它们的树突和电通信。
The GABAergic neurons of the nucleus reticularis thalami that control the communication between thalamus and cortex are interconnected not only through axo-dendritic synapses but also through gap junctions and dendro-dendritic synapses. It is still unknown whether these dendritic communication processes may be triggered both by the tonic and the T-type Ca2+ channel-dependent high frequency burst firing of action potentials displayed by nucleus reticularis neurons during wakefulness and sleep, respectively. Indeed, while it is known that activation of T-type Ca2+ channels actively propagates throughout the dendritic tree, it is still unclear whether tonic action potential firing can also invade the dendritic arborization. Here, using two-photon microscopy, we demonstrated that dendritic Ca2+ responses following somatically evoked action potentials that mimic wake-related tonic firing are detected throughout the dendritic arborization. Calcium influx temporally summates to produce dendritic Ca2+ accumulations that are linearly related to the duration of the action potential trains. Increasing the firing frequency facilitates Ca2+ influx in the proximal but not in the distal dendritic compartments suggesting that the dendritic arborization acts as a low-pass filter in respect to the back-propagating action potentials. In the more distal compartment of the dendritic tree, T-type Ca2+ channels play a crucial role in the action potential triggered Ca2+ influx suggesting that this Ca2+ influx may be controlled by slight changes in the local dendritic membrane potential that determine the T-type channels’ availability. We conclude that by mediating Ca2+ dynamic in the whole dendritic arborization, both tonic and burst firing of the nucleus reticularis thalami neurons might control their dendro-dendritic and electrical communications.
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DOI：
10.1523/jneurosci.4402-11.2012
发表时间：
2012-02-15
期刊：
The Journal of neuroscience : the official journal of the Society for Neuroscience
影响因子：
--
作者：
Crandall SR;Cox CL
通讯作者：
Cox CL
DOI：
10.1196/annals.1403.006
发表时间：
2007-01-01
期刊：
NEUROPROTECTIVE AGENTS: EIGHTH INTERNATIONAL NEUROPROTECTION SOCIETY MEETING
影响因子：
--
作者：
Joksovic, Pavle M.;Covey, Douglas F.;Todorovic, Slobodan M.
通讯作者：
Todorovic, Slobodan M.
影响因子：
16.2
作者：
Acuna-Goycolea, Claudio;Brenowitz, Stephan D.;Regehr, Wade G.
通讯作者：
Regehr, Wade G.
影响因子：
2.5
作者：
Liu, Xiao-Bo;Murray, Karl D.;Jones, Edward G.
通讯作者：
Jones, Edward G.
影响因子：
5.3
作者：
Casale, Amanda E.;McCormick, David A.
通讯作者：
McCormick, David A.