Besing Gai-Linn Kay, St John Emily Kate, Potesta Cobie Victoria, Gallagher Martin J, Zhou Chengwen
Departments of Neurology, Vanderbilt University Medical Center, Nashville, TN, United States.
Neuroscience Graduate Program, Vanderbilt University Medical Center, Nashville, TN, United States.
Front Cell Neurosci. 2022 Oct 14;16:948327. doi: 10.3389/fncel.2022.948327. eCollection 2022.
During non-rapid eye movement (NREM) sleep, cortical neuron activity alternates between a depolarized (firing, up-state) and a hyperpolarized state (down-state) coinciding with delta electroencephalogram (EEG) slow-wave oscillation (SWO, 0. 5-4 Hz) . Recently, we have found that artificial sleep-like up/down-states can potentiate synaptic strength in layer V cortical neurons . Using mouse coronal brain slices, whole cell voltage-clamp recordings were made from layer V cortical pyramidal neurons to record spontaneous excitatory synaptic currents (sEPSCs) and inhibitory synaptic currents (sIPSCs). Artificial sleep-like up/down-states (as SWOs, 0.5 Hz, 10 min, current clamp mode) were induced by injecting sinusoidal currents into layer V cortical neurons. Baseline pre-SWO recordings were recorded for 5 min and post-SWO recordings for at least 25-30 min. Compared to pre-SWO sEPSCs or sIPSCs, post-SWO sEPSCs or sIPSCs in layer V cortical neurons exhibited significantly larger amplitudes and a higher frequency for 30 min. This finding suggests that both sEPSCs and sIPSCs could be potentiated in layer V cortical neurons by the low-level activity of SWOs, and sEPSCs and sIPSCs maintained a balance in layer V cortical neurons during pre- and post-SWO periods. Overall, this study presents an method to show SWO's ability to induce synaptic plasticity in layer V cortical neurons, which may underlie sleep-related synaptic potentiation for sleep-related memory consolidation .
在非快速眼动（NREM）睡眠期间，皮层神经元活动在去极化（放电，兴奋状态）和超极化状态（静息状态）之间交替，这与脑电图（EEG）的δ波慢波振荡（SWO，0.5 - 4赫兹）相一致。最近，我们发现人工模拟睡眠的兴奋/静息状态可增强V层皮层神经元的突触强度。使用小鼠冠状脑片，从V层皮层锥体神经元进行全细胞电压钳记录，以记录自发兴奋性突触电流（sEPSCs）和抑制性突触电流（sIPSCs）。通过向V层皮层神经元注入正弦电流来诱导人工模拟睡眠的兴奋/静息状态（如SWO，0.5赫兹，10分钟，电流钳模式）。在SWO之前记录基线5分钟，之后记录至少25 - 30分钟。与SWO之前的sEPSCs或sIPSCs相比，V层皮层神经元中SWO之后的sEPSCs或sIPSCs在30分钟内表现出明显更大的幅度和更高的频率。这一发现表明，SWO的低水平活动可增强V层皮层神经元中的sEPSCs和sIPSCs，并且在SWO前后期间，sEPSCs和sIPSCs在V层皮层神经元中保持平衡。总体而言，本研究提出了一种方法来展示SWO诱导V层皮层神经元突触可塑性的能力，这可能是与睡眠相关的记忆巩固中睡眠相关突触增强的基础。
