Cell and circuit origins of fast network oscillations in the mammalian main olfactory bulb.
Cell and circuit origins of fast network oscillations in the mammalian main olfactory bulb.
复制标题
哺乳动物主嗅球快速网络振荡的细胞和回路起源。
DOI：
10.7554/elife.74213
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发表时间：
2021-10-18
期刊：
影响因子：
7.7
通讯作者：
Urban NN
中科院分区：
文献类型：
--
作者：
Burton SD;Urban NN
神经同步在整个大脑中产生快速的网络振荡，包括嗅觉系统的第一个处理站——主嗅球（MOB）。识别在MOB中同步神经元的机制将是理解网络振荡如何支持高维感觉空间编码的关键。在这里，利用配对记录和MOB片中肾小球感觉输入的光遗传学激活，我们发现了主二尖瓣细胞（MC）与簇状细胞（TC）尖峰时间同步的深刻差异：TC在快、慢伽马频率上强烈同步，而MC同步较弱，集中在慢伽马频率上。两种细胞类型之间的同步性通过共享肾小球输入而增强，但不依赖于肾小球内外侧兴奋。同步性的细胞类型差异也不能追溯到突触抑制同步性的任何差异。相反，TC大于MC的同步性与共振TC之间比MC更周期性的放电平行，并且以与密集同步网络振荡一致的模式出现。综上所述，我们的研究结果揭示了一种通过不同的TC和MC同步在MOB中并行处理感觉信息的机制，并进一步对比了驱动MOB中快速网络振荡的机制和驱动整个皮层中不规则发射的主要细胞稀疏同步的机制。
Neural synchrony generates fast network oscillations throughout the brain, including the main olfactory bulb (MOB), the first processing station of the olfactory system. Identifying the mechanisms synchronizing neurons in the MOB will be key to understanding how network oscillations support the coding of a high-dimensional sensory space. Here, using paired recordings and optogenetic activation of glomerular sensory inputs in MOB slices, we uncovered profound differences in principal mitral cell (MC) vs. tufted cell (TC) spike-time synchrony: TCs robustly synchronized across fast- and slow-gamma frequencies, while MC synchrony was weaker and concentrated in slow-gamma frequencies. Synchrony among both cell types was enhanced by shared glomerular input but was independent of intraglomerular lateral excitation. Cell-type differences in synchrony could also not be traced to any difference in the synchronization of synaptic inhibition. Instead, greater TC than MC synchrony paralleled the more periodic firing among resonant TCs than MCs and emerged in patterns consistent with densely synchronous network oscillations. Collectively, our results thus reveal a mechanism for parallel processing of sensory information in the MOB via differential TC vs. MC synchrony, and further contrast mechanisms driving fast network oscillations in the MOB from those driving the sparse synchronization of irregularly firing principal cells throughout cortex.