Krembil Brain Institute, University Health Network, Toronto, ON, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada.
Krembil Brain Institute, University Health Network, Toronto, ON, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada; Department of Electrical and Computer Engineering, University of Toronto, Toronto, ON, Canada; Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada; Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, ON, Canada.
Cell Rep. 2024 May 28;43(5):114189. doi: 10.1016/j.celrep.2024.114189. Epub 2024 May 3.
The propagation of a seizure wavefront in the cortex divides an intensely firing seizure core from a low-firing seizure penumbra. Seizure propagation is currently thought to generate strong activation of inhibition in the seizure penumbra that leads to its decreased neuronal firing. However, the direct measurement of neuronal excitability during seizures has been difficult to perform in vivo. We used simultaneous optogenetics and calcium imaging (all-optical interrogation) to characterize real-time neuronal excitability in an acute mouse model of seizure propagation. We find that single-neuron excitability is decreased in close proximity to the seizure wavefront but becomes increased distal to the seizure wavefront. This suggests that inhibitory neurons of the seizure wavefront create a proximal circumference of hypoexcitability but do not influence neuronal excitability in the penumbra.
在皮层中，癫痫波阵面的传播将高强度放电的癫痫核心区与低强度放电的癫痫半影区分开。目前认为，癫痫传播会在癫痫半影区产生强烈的抑制激活，从而导致其神经元放电减少。然而，在体内直接测量癫痫发作期间神经元兴奋性一直很困难。我们使用同时的光遗传学和钙成像（全光学询问）来描述在癫痫传播的急性小鼠模型中实时神经元兴奋性。我们发现，在接近癫痫波阵面的单个神经元兴奋性降低，但在远离癫痫波阵面的神经元兴奋性增加。这表明癫痫波阵面的抑制性神经元在近端形成了一个低兴奋性的圆周，但不会影响癫痫半影区的神经元兴奋性。
