TRANSIENT-RESPONSE IN A DENDRITIC NEURON MODEL FOR CURRENT INJECTED AT ONE BRANCH
TRANSIENT-RESPONSE IN A DENDRITIC NEURON MODEL FOR CURRENT INJECTED AT ONE BRANCH
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DOI：
10.1016/s0006-3495(74)85948-5
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发表时间：
1974-01-01
影响因子：
3.4
通讯作者：
RALL, W
中科院分区：
文献类型：
--
作者：
RINZEL, J;RALL, W
得到了分支树突状神经元模型中瞬时脉冲电流注入单个树突状分支时的响应函数的数学表达式。该理论模型假设了被动膜的特性和分支直径的等效圆柱体约束。当在卷积公式中使用响应函数时，可以计算给定输入位置的任意电流注入在树突状树中任何指定点的瞬态电压。一个特定的数值例子，在分支末端的短暂电流注入，说明了去极化峰在整个神经元模型中扩散时的衰减和延迟特性。与从分支输入点到胞体的电压瞬变的严重衰减相反，实际传递到胞体和其他树的总输入电荷的比例计算为大约一半。这个分数与输入时间过程无关。其他比较分支终端输入位点与体细胞输入位点的数值示例表明，对于给定的瞬态电流注入，峰值去极化与注入位点的输入电阻不成比例，对于给定的突触电导瞬态，有效突触驱动电位可以显著降低，导致分支输入位点的突触电流和电荷减少。此外，对于突触的情况，两种输入的比较是基于在胞体看到的兴奋性突触后电位（EPSP）和传递到胞体的总电荷。
Mathematical expressions are obtained for the response function corresponding to an instantaneous pulse of current injected to a single dendritic branch in a branched dendritic neuron model. The theoretical model assumes passive membrane properties and the equivalent cylinder constraint on branch diameters. The response function when used in a convolution formula enables one to compute the voltage transient at any specified point in the dendritic tree for an arbitrary current injection at a given input location. A particular numerical example, for a brief current injection at a branch terminal, illustrates the attenuation and delay characteristics of the depolarization peak as it spreads throughout the neuron model. In contrast to the severe attenuation of voltage transients from branch input sites to the soma, the fraction of total input charge actually delivered to the soma and other trees is calculated to be about one-half. This fraction is independent of the input time course. Other numerical examples, which compare a branch terminal input site with a soma input site, demonstrate that, for a given transient current injection, the peak depolarization is not proportional to the input resistance at the injection site and, for a given synaptic conductance transient, the effective synaptic driving potential can be significantly reduced, resulting in less synaptic current flow and charge, for a branch input site. Also, for the synaptic case, the two inputs are compared on the basis of the excitatory post-synaptic potential (EPSP) seen at the soma and the total charge delivered to the soma.