Rathour Rahul Kumar, Kaphzan Hanoch
Sagol Department of Neurobiology, University of Haifa, Haifa, Israel.
Front Cell Neurosci. 2022 Jul 22;16:906313. doi: 10.3389/fncel.2022.906313. eCollection 2022.
The prerequisites for neurons to function within a circuit and be able to contain and transfer information efficiently and reliably are that they need to be homeostatically stable and fire within a reasonable range, characteristics that are governed, among others, by voltage-gated ion channels (VGICs). Nonetheless, neurons entail large variability in the expression levels of VGICs and their corresponding intrinsic properties, but the role of this variability in information transfer is not fully known. In this study, we aimed to investigate how this variability of VGICs affects information transfer. For this, we used a previously derived population of neuronal model neurons, each with the variable expression of five types of VGICs, fast Na, delayed rectifier K, A-type K, T-type Ca, and HCN channels. These analyses showed that the model neurons displayed variability in mutual information transfer, measured as the capability of neurons to successfully encode incoming synaptic information in output firing frequencies. Likewise, variability in the expression of VGICs caused variability in EPSPs and IPSPs amplitudes, reflected in the variability of output firing frequencies. Finally, using the virtual knockout methodology, we show that among the ion channels tested, the A-type K channel is the major regulator of information processing and transfer.
神经元要在一个回路中发挥功能,并能够高效且可靠地存储和传递信息,其前提条件是它们需要在稳态上保持稳定,并在合理范围内放电,这些特性尤其受电压门控离子通道(VGICs)的调控。尽管如此,神经元在VGICs的表达水平及其相应的内在特性方面存在很大的变异性,但这种变异性在信息传递中的作用尚未完全明确。在本研究中,我们旨在探究VGICs的这种变异性是如何影响信息传递的。为此,我们使用了先前推导的一群神经元模型,每个模型神经元对五种类型的VGICs(快速钠通道、延迟整流钾通道、A型钾通道、T型钙通道和超极化激活的环核苷酸门控通道)具有可变表达。这些分析表明,模型神经元在互信息传递方面表现出变异性,互信息传递以神经元在输出放电频率中成功编码传入突触信息的能力来衡量。同样,VGICs表达的变异性导致了兴奋性突触后电位(EPSPs)和抑制性突触后电位(IPSPs)幅度的变异性,这反映在输出放电频率的变异性上。最后,使用虚拟敲除方法,我们表明在所测试的离子通道中,A型钾通道是信息处理和传递的主要调节因子。