Two photon data from: Functional and structural properties of highly responsive somatosensory neurons in mouse barrel cortex

Sparse population activity is a hallmark of supra-granular sensory neurons in neocortex. The mechanisms underlying sparseness are not well understood because a direct link between the neurons activated in vivo and their cellular properties investigated in vitro has been missing. We used two-photon calcium imaging to identify a subset of neurons in layer L2/3 (L2/3) of mouse primary somatosensory cortex that are highly active following principal whisker vibrotactile stimulation. These high responders were then tagged using photoconvertible green fluorescent protein for subsequent targeting in the brain slice using intracellular patch-clamp recordings and biocytin staining. This approach allowed us to investigate the structural and functional properties of high responders that distinguish them from less active control cells. Compared to less responsive L2/3 neurons, high responders displayed increased levels of stimulus-evoked and spontaneous activity, elevated noise and spontaneous pair-...

群体活动稀疏性是新皮层颗粒上层感觉神经元的标志性特征。目前学界对该稀疏性背后的机制尚未形成充分认知，核心障碍在于在体激活的神经元与其体外研究所阐明的细胞特性之间始终缺乏直接关联。本研究采用双光子钙成像（two-photon calcium imaging）技术，在小鼠初级体感皮层第2/3层（L2/3）中，筛选出经主胡须振动触觉刺激后呈现高激活状态的神经元亚群。随后，研究人员借助光转换绿色荧光蛋白（photoconvertible green fluorescent protein）对这些高响应神经元进行标记，以便后续在脑片标本中通过细胞内膜片钳记录（intracellular patch-clamp recordings）与生物胞素染色（biocytin staining）技术开展靶向研究。该方法使得我们能够深入探究高响应神经元区别于低活性对照细胞的结构与功能特性。相较于低响应的第2/3层神经元，高响应神经元展现出更高水平的刺激诱发及自发放电活动，同时伴随噪声水平升高与自发放电成对（spontaneous pair-...）。