Role of dendritic conductances on the neuronal output

描述(由申请人提供)： 神经元传递其突触群体活动的方式 对动作电位的输入是理解的基本步骤 大脑中的信息处理。通过使用计算机模拟 突触输入和体外脑片电生理学我们将研究三个 能够影响投入向产出转化的重要因素。这个 首先是树突状细胞的电导率：细胞的放电率是否相同 输入是注入树突还是胞体？Will树枝状 已被证明能促进个体、阈值下、突触的电导 电位也促进了阈值以上的突触输入序列？一秒钟 影响因素是输入在 树状结构树，它可以确定如何组合输入。无源电缆 理论预测，如果输入出现在同一树枝上，则次线性求和 由于相互分流而产生的分支，以及如果它们出现在不同的 分支，但活跃的树枝状电导会与次线性求和相反吗？ 我们将研究的第三个因素是兴奋性和 树突状细胞上的抑制性突触输入。我们将主要关注如何 抑制对放电的影响取决于抑制输入的位置。 位于相对于兴奋性的位置。在所有三种情况下，我们都将使用通道 阻滞剂用于确定导致非线性的树枝状电导 我们可以在从输入到输出的转换过程中看到效果。

DESCRIPTION (provided by applicant): The way in which a neuron transduces the population activity of its synaptic inputs into action potentials is a fundamental step in understanding information processing in the brain. Through the use of computer simulated synaptic inputs and in vitro slice electrophysiology we will examine three important factors that can affect the transformation of inputs to output. The first is the rate of dendriticconductances: is the cell's firing rate the same whether the inputs are injected in the dendrite or the soma? Will dendritic conductances that have been shown to boost individual, subthreshold, synaptic potentials also boost suprathreshold trains of synaptic inputs? A second influential factor is the location of the inputs relative to each other on the dendritic tree, which may determine how the inputs are combined. Passive cable theory predicts sublinear summation if the inputs occur on the same dendritic branch due to mutual shunt, and linear summation if they occur on different branches, but will active dendritic conductances counter sublinear summation? The third factor we will examine is the interaction between excitatory and inhibitory synaptic inputs on the dendritic tree. We will mainly focus on how the effects of inhibition on firing depend on where the inhibitory inputs are located relative to the excitatory. In all three cases we will use channel blockers to identifythe dendritic conductances responsible for the nonlinear effects we may see in the transduction from input to output.