Subthreshold glutamate release from mitral cell dendrites.
Subthreshold glutamate release from mitral cell dendrites.
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DOI：
10.1523/jneurosci.5606-08.2009
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发表时间：
2009-05-27
期刊：
影响因子：
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通讯作者：
Urban NN
中科院分区：
文献类型：
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作者：
Castro JB;Urban NN
许多神经元类型的树突起突触前结构的作用，在动作电位和树突棘波之后释放递质。在这方面，树突可以像轴突一样起作用，在阈上电事件之后产生离散输出。然而，作为突触输入的主要站点，树突经历持续的阈下波动的膜电位，提出了这些阈下变化是否会导致递质释放的变化的问题。在这里，我们表明，副嗅球的僧帽细胞释放谷氨酸从他们的树突在响应亚和阈上刺激。虽然在对照条件下阈下输出通常较低，但可通过药理学或内源性激活I组代谢型谷氨酸受体（mGluRs）将其增强数倍。这些结果表明，突触前树突可以支持两种不同形式的输出，并可以动态调节电活动如何耦合到递质释放。
The dendrites of a number of neuron types function as presynaptic structures, releasing transmitter following action potentials and dendritic spikes. In this regard, dendrites can function like axons, producing discrete outputs following suprathreshold electrical events. However, as the major site of synaptic inputs, dendrites experience ongoing subthreshold fluctuations in membrane potential, raising the question of whether these subthreshold changes can cause changes in transmitter release. Here we show that mitral cells of the accessory olfactory bulb release glutamate from their dendrites in response to both sub- and suprathreshold stimuli. While subthreshold output was typically low under control conditions, it could be enhanced several fold by pharmacological or endogenous activation of group I metabotropic glutamate receptors (mGluRs). These results indicate that presynaptic dendrites can support two distinct forms of output, and can dynamically regulate how electrical activity is coupled to transmitter release.