Liu Ming, Sun Xiaojuan
School of Science, Beijing University of Posts and Telecommunications, Beijing, 100876, China.
Key Laboratory of Mathematics and Information Networks (Beijing University of Posts and Telecommunications), Ministry of Education, Beijing, 100876, China.
Sci Rep. 2024 Dec 5;14(1):30278. doi: 10.1038/s41598-024-81655-w.
Neurons receive synaptic inputs with diverse temporal patterns in vivo, and their integration of these patterns is critical for understanding information processing mechanisms in the brain. Fast-spiking basket cells, which perform both supralinear and sublinear dendritic integration, are essential for inhibitory control in the hippocampus. However, their responses and the mechanisms underlying different temporal input patterns remain unclear. To address this question, we apply inputs with varying windows of time to a detailed compartmental model of basket cells. Our results reveal that when synaptic inputs are randomly dispersed, temporal integration in FS BCs exhibits a sigmoid-like response within the temporal window. In contrast, synchronous input protocols more effectively elicit action potentials, while asynchronous inputs generate more spikes in response to suprathreshold stimuli. Further analysis shows that the supralinear dendrites of fast-spiking basket cells primarily mediate this nonlinearity to asynchronous inputs, owing to their larger dendritic diameters. Moreover, we discover that delayed rectifier [Formula: see text] channels reduce sensitivity to synchronous inputs, whereas N-type [Formula: see text] channels enhance sensitivity to asynchronous inputs. These results provide insights into the mechanisms underlying the temporal coding of fast-spiking basket cells, which is crucial for understanding their role in neuronal oscillations.
在体内,神经元会接收到具有不同时间模式的突触输入,而它们对这些模式的整合对于理解大脑中的信息处理机制至关重要。快速放电篮状细胞既能进行超线性也能进行亚线性树突整合,对海马体中的抑制性控制至关重要。然而,它们的反应以及不同时间输入模式背后的机制仍不清楚。为了解决这个问题,我们将具有不同时间窗口的输入应用于篮状细胞的详细 compartmental 模型。我们的结果表明,当突触输入随机分散时,FS 篮状细胞中的时间整合在时间窗口内呈现出 S 形反应。相比之下,同步输入协议更有效地引发动作电位,而异步输入在响应阈上刺激时会产生更多的尖峰。进一步分析表明,快速放电篮状细胞的超线性树突主要由于其较大的树突直径,介导了对异步输入的这种非线性。此外,我们发现延迟整流钾通道降低了对同步输入的敏感性,而 N 型钙通道增强了对异步输入的敏感性。这些结果为快速放电篮状细胞时间编码背后的机制提供了见解,这对于理解它们在神经元振荡中的作用至关重要。