Rapid BDNF-induced retrograde synaptic modification in a developing retinotectal system
Rapid BDNF-induced retrograde synaptic modification in a developing retinotectal system
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DOI：
10.1038/nature02618
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发表时间：
2004-06-24
期刊：
影响因子：
64.8
通讯作者：
Poo, MM
中科院分区：
文献类型：
--
作者：
Du, JL;Poo, MM
在海马神经元培养物中，通过重复突触活动诱导长期突触增强或抑制，分别伴随着从轴突输出处的诱导部位到突触前神经元树突上的输入突触的增强或抑制的逆行扩散（1，2）。我们在这里报告，快速逆行突触修饰也存在于一个完整的发展视网膜顶盖系统。局部应用脑源性神经营养因子（BDNF）的非洲爪蟾视顶盖，诱导视网膜顶盖突触的持续增强，导致快速修改的突触输入在树突的视网膜神经节细胞（RGC），所示的持续增强的光诱发的兴奋性突触电流和尖峰活动的RGC。这种逆行效应需要TrkB受体激活，磷脂酶C γ活性和RGC中的Ca2+升高，并通过RGC树突处突触后AMPA亚型谷氨酸受体数量的选择性增加来解释。神经元中的这种逆行信息流允许根据轴突终末接收的信号快速调节树突处的突触输入，这一过程让人想起神经网络中用于学习的反向传播算法（3）。
In cultures of hippocampal neurons, induction of long-term synaptic potentiation or depression by repetitive synaptic activity is accompanied by a retrograde spread of potentiation or depression, respectively, from the site of induction at the axonal outputs to the input synapses on the dendrites of the presynaptic neuron(1,2). We report here that rapid retrograde synaptic modification also exists in an intact developing retinotectal system. Local application of brain-derived neurotrophic factor ( BDNF) to the Xenopus laevis optic tectum, which induced persistent potentiation of retinotectal synapses, led to a rapid modification of synaptic inputs at the dendrites of retinal ganglion cells (RGCs), as shown by a persistent enhancement of light-evoked excitatory synaptic currents and spiking activity of RGCs. This retrograde effect required TrkB receptor activation, phospholipase Cgamma activity and Ca2+ elevation in RGCs, and was accounted for by a selective increase in the number of postsynaptic AMPA-subtype glutamate receptors at RGC dendrites. Such retrograde information flow in the neuron allows rapid regulation of synaptic inputs at the dendrite in accordance to signals received at axon terminals, a process reminiscent of back-propagation algorithm for learning in neural networks(3).