Volen Center for Complex Systems and Biology Department, Brandeis University, Waltham, Massachusetts 02454, USA.
J Neurosci. 2010 Mar 31;30(13):4687-92. doi: 10.1523/JNEUROSCI.2998-09.2010.
Many neurons exhibit postinhibitory rebound (PIR), in which neurons display enhanced excitability following inhibition. PIR can strongly influence the timing of spikes on rebound from an inhibitory input. We studied PIR in the lateral pyloric (LP) neuron of the stomatogastric ganglion of the crab Cancer borealis. The LP neuron is part of the pyloric network, a central pattern generator that normally oscillates with a period of approximately 1 s. We used the dynamic clamp to create artificial rhythmic synaptic inputs of various periods and duty cycles in the LP neuron. Surprisingly, we found that the strength of PIR increased slowly over multiple cycles of synaptic input. Moreover, this increased excitability persisted for 10-20 s after the rhythmic inhibition was removed. These effects are considerably slower than the rhythmic activity typically observed in LP. Thus this slow postinhibitory rebound allows the neuron to adjust its level of excitability to the average level of inhibition over many cycles, and is another example of an intrinsic "short-term memory" mechanism.
许多神经元表现出后抑制反弹（PIR），即在抑制后神经元显示出增强的兴奋性。PIR 可以强烈影响从抑制性输入反弹时的尖峰时间。我们研究了北方滨蟹口胃神经节的外侧幽门（LP）神经元中的 PIR。LP 神经元是幽门网络的一部分，是一种中央模式发生器，通常以大约 1 秒的周期振荡。我们使用动态钳位在 LP 神经元中创建具有各种周期和占空比的人工节律性突触输入。令人惊讶的是，我们发现 PIR 的强度在多个突触输入周期中缓慢增加。此外，这种兴奋性增加在节律性抑制去除后持续 10-20 秒。这些效应比通常在 LP 中观察到的节律性活动慢得多。因此，这种缓慢的后抑制反弹允许神经元根据多个周期的平均抑制水平调整其兴奋性水平，这是内在“短期记忆”机制的另一个例子。
