BDNF regulates the intrinsic excitability of cortical neurons.
BDNF regulates the intrinsic excitability of cortical neurons.
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DOI：
10.1101/lm.6.3.284
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发表时间：
1999-05
影响因子：
2
通讯作者：
Niraj S. Desai;L. C. Rutherford;G. Turrigiano
中科院分区：
文献类型：
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作者：
Niraj S. Desai;L. C. Rutherford;G. Turrigiano
新皮质锥体神经元通过调节它们的内向和外向电流的平衡来响应长时间的活动阻断，从而对突触输入变得更加敏感，这可能是在突触数量或强度强烈变化期间内稳态调节放电率的一种手段。在这里，我们表明，这种活动依赖性调节的内在兴奋性依赖于神经营养因子脑源性神经营养因子（BDNF）。在大鼠视皮层培养物的实验中，我们发现外源性BDNF阻止，TrkB-IgG融合蛋白复制，活动阻断产生的锥体神经元兴奋性的变化。这些效应中的大多数也在双极中间神经元中观察到，表明BDNF在调节神经元兴奋性中具有非常普遍的作用。此外，早期的工作已经证明，BDNF介导的不同类型的稳态可塑性存在于这些相同的文化：缩放的AMPA介导的突触输入的量子幅度向上或向下作为活动的函数。综上所述，这些结果表明，BDNF可能是控制突触和内在特性的协调调节的信号，目的是让皮层网络适应长期持续的活动变化。
Neocortical pyramidal neurons respond to prolonged activity blockade by modulating their balance of inward and outward currents to become more sensitive to synaptic input, possibly as a means of homeostatically regulating firing rates during periods of intense change in synapse number or strength. Here we show that this activity-dependent regulation of intrinsic excitability depends on the neurotrophin brain-derived neurotrophic factor (BDNF). In experiments on rat visual cortical cultures, we found that exogenous BDNF prevented, and a TrkB-IgG fusion protein reproduced, the change in pyramidal neuron excitability produced by activity blockade. Most of these effects were also observed in bipolar interneurons, indicating a very general role for BDNF in regulating neuronal excitability. Moreover, earlier work has demonstrated that BDNF mediates a different kind of homeostatic plasticity present in these same cultures: scaling of the quantal amplitude of AMPA-mediated synaptic inputs up or down as a function of activity. Taken together, these results suggest that BDNF may be the signal controlling a coordinated regulation of synaptic and intrinsic properties aimed at allowing cortical networks to adapt to long-lasting changes in activity.