当前位置: X-MOL 学术Front. Cell. Neurosci. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Developmentally Regulated Rebound Depolarization Enhances Spike Timing Precision in Auditory Midbrain Neurons.
Frontiers in Cellular Neuroscience ( IF 5.3 ) Pub Date : 2020-07-06 , DOI: 10.3389/fncel.2020.00236
Hongyu Sun 1 , Hui Zhang 1 , Alysia Ross 1 , Ting Ting Wang 1 , Aycheh Al-Chami 1 , Shu Hui Wu 1
Affiliation  

The inferior colliculus (IC) is an auditory midbrain structure involved in processing biologically important temporal features of sounds. The responses of IC neurons to these temporal features reflect an interaction of synaptic inputs and neuronal biophysical properties. One striking biophysical property of IC neurons is the rebound depolarization produced following membrane hyperpolarization. To understand how the rebound depolarization is involved in spike timing, we made whole-cell patch clamp recordings from IC neurons in brain slices of P9–21 rats. We found that the percentage of rebound neurons was developmentally regulated. The precision of the timing of the first spike on the rebound increased when the neuron was repetitively injected with a depolarizing current following membrane hyperpolarization. The average jitter of the first spikes was only 0.5 ms. The selective T-type Ca2+ channel antagonist, mibefradil, significantly increased the jitter of the first spike of neurons in response to repetitive depolarization following membrane hyperpolarization. Furthermore, the rebound was potentiated by one to two preceding rebounds within a few hundred milliseconds. The first spike generated on the potentiated rebound was more precise than that on the non-potentiated rebound. With the addition of a calcium chelator, BAPTA, into the cell, the rebound potentiation no longer occurred, and the precision of the first spike on the rebound was not improved. These results suggest that the postinhibitory rebound mediated by T-type Ca2+ channel promotes spike timing precision in IC neurons. The rebound potentiation and precise spikes may be induced by increases in intracellular calcium levels.



中文翻译:

发展调节的回弹去极化增强了听觉中脑神经元的峰值定时精度。

下丘脑(IC)是一种听觉中脑结构,参与处理声音的生物学上重要的时态特征。IC神经元对这些时间特征的反应反映了突触输入和神经元生物物理特性的相互作用。IC神经元的一项惊人的生物物理特性是膜超极化后产生的反弹去极化。为了了解反弹去极化与尖峰时间的关系,我们从P9-21大鼠脑切片的IC神经元制作了全细胞膜片钳记录。我们发现反弹神经元的百分比受到发育调节。当在膜超极化后向神经元重复注入去极化电流时,反弹的第一个峰值的计时精度会提高。第一个峰值的平均抖动仅为0.5 ms。选择性T型钙2+通道拮抗剂米贝拉地尔(Mibefradil)显着增加了神经元第一个尖峰的抖动,以响应膜超极化后的重复去极化。此外,反弹在几百毫秒内被一到两个先前的反弹增强。增强反弹产生的第一个尖峰比非增强反弹产生的第一个峰值更精确。在细胞中添加钙螯合剂BAPTA后,不再发生反弹增强,并且反弹的第一个加标峰的精度也没有提高。这些结果表明,由T型Ca 2+介导的抑制后反弹通道可提高IC神经元的尖峰定时精度。细胞内钙水平的升高可诱导反弹增强和精确的峰值。

更新日期:2020-08-06
down
wechat
bug