Until recently, glia, which exceeds the number of neurons, was considered to only have supportive roles in the central nervous system, providing homeostatic controls and metabolic supports. However, recent studies suggest that glia interacts with neurons and plays active roles in information processing within neuronal circuits. To elucidate how glia contributes to neuronal information processing, we simulated a sensory neuron-glia (neuron-astrocyte) network model. It was investigated in association with ambient (extracellular) GABA level, because the astrocyte has a major role in removing extracellular GABA molecules. In the network model, transporters, embedded in plasma membranes of astrocytes, modulated local ambient GABA levels by actively removing extracellular GABA molecules which persistently acted on receptors in membranes outside synapses and provided pyramidal cells with inhibitory currents. Gap-junction coupling between astrocytes mediated a concordant decrease in local ambient GABA levels, which solicited a prompt population response of pyramidal cells (i.e., activation of an ensemble of pyramidal cells) to a sensory stimulus. As a consequence, the reaction time of a motor network, to which axons of pyramidal cells of the sensory network project, to the sensory stimulus was shortened. We suggest that the astrocytic gap-junction coupling may assist in organizing dynamic cell assemblies by coordinating a reduction in local ambient GABA levels, thereby shortening reaction time to sensory stimulation.

中文翻译：

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细胞外GABA有助于组织动态细胞装配，以缩短对感觉刺激的反应时间。

直到最近，神经胶质的数量超过了神经元的数量，人们才认为它在中枢神经系统中仅具有支持作用，提供稳态控制和代谢支持。但是，最近的研究表明，神经胶质与神经元相互作用，并在神经元回路内的信息处理中发挥积极作用。为了阐明神经胶质细胞如何促进神经元信息处理，我们模拟了感觉神经胶质细胞（神经元-星形胶质细胞）网络模型。由于星形胶质细胞在去除细胞外GABA分子中起主要作用，因此已与周围（细胞外）GABA水平进行了研究。在网络模型中，转运蛋白嵌入星形胶质细胞的质膜中，通过主动去除持续作用于突触外膜上受体的细胞外GABA分子，调节局部周围GABA水平，并为锥体细胞提供抑制电流。星形胶质细胞之间的间隙连接偶联介导局部周围GABA水平的一致降低，这引起了锥体细胞对感觉刺激的迅速种群反应（即，锥体细胞集合的激活）。结果，缩短了感觉网络的锥体细胞的轴突投射到其中的运动网络对感觉刺激的反应时间。我们建议，星形胶质细胞间隙连接偶联可能通过协调局部环境GABA水平的降低来协助组织动态细胞装配，从而缩短对感觉刺激的反应时间。