论文标题
突触受体动力学的扩散捕获模型中的局部积累时间
Local accumulation times in a diffusion-trapping model of synaptic receptor dynamics
论文作者
论文摘要
神经元突触后膜内神经递质受体的横向扩散和捕获在确定突触强度和可塑性方面起着关键作用。诱捕是由受体与突触中脚手架蛋白（插槽）的可逆结合所介导的。在本文中，我们介绍了一种新方法，用于分析受体运输扩散模型中突触的瞬态动力学。给定空间分布的突触群体，每个突触都有固定数量的插槽，我们根据一组局部累积时间计算了绑定插槽（突触重量）的稳态分布（突触重量）的稳态分布。假设胞吐作用和内吞作用的速率足够慢，我们表明稳态突触权重彼此独立（纯粹是局部）。另一方面，给定突触的局部积累时间取决于插槽数量和所有突触的空间位置，表明瞬时异突触可塑性形式。这表明局部积累时间测量可以提供有关树突中突触权重的分布的有用信息。
The lateral diffusion and trapping of neurotransmitter receptors within the postsynaptic membrane of a neuron plays a key role in determining synaptic strength and plasticity. Trapping is mediated by the reversible binding of receptors to scaffolding proteins (slots) within a synapse. In this paper we introduce a new method for analyzing the transient dynamics of synapses in a diffusion-trapping model of receptor trafficking. Given a population of spatially distributed synapses, each of which has a fixed number of slots, we calculate the rate of relaxation to the steady-state distribution of bound slots (synaptic weights) in terms of a set of local accumulation times. Assuming that the rates of exocytosis and endocytosis are sufficiently slow, we show that the steady-state synaptic weights are independent of each other (purely local). On the other hand, the local accumulation time of a given synapse depends on the number of slots and the spatial location of all the synapses, indicating a form of transient heterosynaptic plasticity. This suggests that local accumulation time measurements could provide useful information regarding the distribution of synaptic weights within a dendrite.
