Department of Neurobiology and Behavior, University of California, Irvine, CA, USA.
Center for the Neurobiology of Learning and Memory, University of California, Irvine, CA, USA.
Sci Rep. 2020 Dec 8;10(1):21441. doi: 10.1038/s41598-020-78179-4.
Stroke is a leading cause of death and the leading cause of long-term disability, but its electrophysiological basis is poorly understood. Characterizing acute ischemic neuronal activity dynamics is important for understanding the temporal and spatial development of ischemic pathophysiology and determining neuronal activity signatures of ischemia. Using a 32-microelectrode array spanning the depth of cortex, electrophysiological recordings generated for the first time a continuous spatiotemporal profile of local field potentials (LFP) and multi-unit activity (MUA) before (baseline) and directly after (0-5 h) distal, permanent MCA occlusion (pMCAo) in a rat model. Although evoked activity persisted for hours after pMCAo with minor differences from baseline, spatiotemporal analyses of spontaneous activity revealed that LFP became spatially and temporally synchronized regardless of cortical depth within minutes after pMCAo and extended over large parts of cortex. Such enhanced post-ischemic synchrony was found to be driven by increased bursts of low multi-frequency oscillations and continued throughout the acute ischemic period whereas synchrony measures minimally changed over the same recording period in surgical sham controls. EEG recordings of a similar frequency range have been applied to successfully predict stroke damage and recovery, suggesting clear clinical relevance for our rat model.
中风是导致死亡和长期残疾的主要原因，但它的电生理基础仍未被充分理解。描述急性缺血性神经元活动的动态变化对于理解缺血性病理生理学的时空发展以及确定缺血性神经元活动特征非常重要。使用跨越皮层深度的 32 个微电极阵列，首次在大鼠模型中远端永久性 MCA 闭塞（pMCAo）前（基线）和直接后（0-5 小时）生成了局部场电位（LFP）和多单位活动（MUA）的连续时空分布图谱。尽管在 pMCAo 后几个小时内诱发性活动持续存在，与基线相比仅有微小差异，但自发活动的时空分析表明，LFP 在 pMCAo 后几分钟内无论皮层深度如何，都变得在空间和时间上同步，并且扩展到大脑皮层的大部分区域。这种增强的缺血后同步性是由低频振荡的爆发增加驱动的，并在整个急性缺血期间持续存在，而在相同的记录期间，同步性测量几乎没有变化。在手术假对照中。类似频率范围的 EEG 记录已成功用于预测中风损伤和恢复，这表明我们的大鼠模型具有明显的临床相关性。
