The Nanoneedle Net: A flexible and transparent 3D nanoelectrode array for mapping intracellular dendritic dynamics at the cortical surface

Nanoneedle Net：一种灵活且透明的 3D 纳米电极阵列，用于绘制皮质表面的细胞内树突动力学

• 批准号: 10378637
• 负责人: Krishna jayant
• 金额: $ 15.22万
• 依托单位: PURDUE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-05-07 至 2024-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10378637
• 关键词: 3-Dimensional; Action Potentials; Acute; Amplifiers; Animals; Apical; Back; Biological Assay; Brain; Brain region; Calcium; Caliber; Cells; Code; Complex; Custom; Dendrites; Distal; Electrodes; Electronics; Electrophysiology (science); Engineering; Esthesia; Event; Exhibits; Feedback; Film; Financial compensation; Functional disorder; Goals; Gold; Height; Image; Injections; Lasers; Light; Link; Lipids; Location; Maps; Measures; Membrane; Membrane Potentials; Mental disorders; Methods; Modernization; Morphologic artifacts; Morphology; Mus; N-Methylaspartate; Needles; Neurons; Neurosciences; Noise; Output; Pattern; Penetration; Phase; Population; Property; Quartz; Registries; Reporting; Role; Shapes; Signal Transduction; Silicon; Site; Slice; Sodium; Somatosensory Cortex; Sorting - Cell Movement; Structure; Surface; Synapses; Techniques; Texture; Thick; Thinness; Touch sensation; Trees; Validation; Vibrissae; awake; barrel cortex; density; electric impedance; extracellular; flexibility; hippocampal pyramidal neuron; in vivo; information processing; interest; membrane model; nanoelectrode array; nanoelectrodes; nanoneedle; nanoscale; nervous system disorder; neural circuit; neuronal cell body; optogenetics; parylene; regenerative; relating to nervous system; seal; sensory input; spatiotemporal; temporal measurement; tool; two photon microscopy; two-photon; voltage

Project Summary Neurons in the mammalian brain possess elaborate tree-like structures termed dendrites. These dendritic branches with distinctive morphological features compartmentalize and shape synaptic inputs, which eventually propagate to the soma to form the action-potential output (AP) – the unit currency of information transfer in the brain. Unravelling how dendrites transform complex synaptic inputs into AP output, shape population-level brain activity, and drive sensory input fundamental to our understanding of neural circuit mechanisms and brain function. Of particular interest are the distal dendrites of layer 5 pyramidal neurons in the barrel cortex, whose somatic output transfers sensorimotor information to a myriad of brain regions. These deep-layer pyramidal neurons extend their dendrites vertically into the most superficial layer of the cortex where they integrate extensive inputs from diverse brain regions, and exhibit a myriad of regenerative feedback events (E.g.: NMDA, Calcium, Sodium spikes), which are believed to be fundamental to controlling the overall input-output-gain of the neuron. However, the spatio-temporal dynamics of dendritic activity, and the overall relationship between dendritic and somatic gain in vivo remains unknown. The small size of these dendrites (~2 µm in diameter) and their location (<100 µm from the surface) has rendered conventional whole-cell electrophysiology infeasible – the current gold-standard; while the proposed alternative approaches, such as calcium imaging, lack temporal resolution to report fast sub-threshold membrane dynamics that underlie neural computation. Here, we aim to map the electrical dynamics of distal apical dendrites in the somatosensory cortex of awake behaving mice using a flexible and transparent vertical nanoelectrode platform termed ‘The Nanoneedle Net’. The Net will comprise of 256 channels with 128 planar electrodes and 128 vertical needles. Each needle will be 40-60 µm in height, ~100 nm in tip diameter, and lipid-coated to facilitate seamless penetration into a membrane. Our custom fabricated array (electrode pitch of 20 µm) once placed on the surface of the brain will allow the needles to penetrate <60 µm deep and form a tight electrical seal with distal dendritic branches. Readout will be accomplished through heavily multiplexed low noise custom CMOS amplifiers. To corroborate the origins of both planar surface recordings and nanoneedle dendritic recordings in vivo, we will combine conventional intra- and extracellular ground-truth electrophysiology, two-photon calcium imaging, optogenetics, spike sorting using template matching, and whisker touch. Ultimately, this platform will not only allow us to establish the computational rules by which distal dendrites shape cortical output during active sensation, but provide a universal method to probe dendritic integration in the living brain.

项目摘要 哺乳动物大脑中的神经元具有精美的树状结构，称为树突。这些树突状 具有独特形态特征分隔和形状突触输入的分支，有时 传播到SOMA以形成动感电位输出（AP） - 信息转移的单位货币 脑。揭开树突如何将复杂的突触输入转化为AP输出，形状人口级的大脑 活动，并驱动我们对神经回路机制和大脑的理解的感官输入 功能。特别令人感兴趣的是枪管皮层中5层锥体神经元的盘状树突 躯体输出将感觉运动信息传输到无数的大脑区域。这些深层金字塔 神经元将树突垂直扩展到皮质的最浅层层中 潜水大脑区域的广泛输入，并展示了无数的再生反馈事件（例如：NMDA， 钙，钠尖峰），据信这是控制总体投入输出生成的基础 神经元。但是，树突活性的时空动力学以及 在体内树突状和体细胞增益仍然未知。这些树突的小尺寸（直径约2 µm）和 它们的位置（距地面<100 µm）使常规的全细胞电生理学变得不可行 - 当前的金标准；虽然提出的替代方法（例如钙成像）缺乏暂时的 分辨率报告基于神经元计算的快速子阈值膜动力学。 在这里，我们旨在绘制醒目的体感皮层中盘状顶端树突的电动动力学 使用柔性且透明的垂直纳米电极平台表现为“纳米净网”。 网将组成256个通道，其中有128个平面电极和128个垂直针。每针将是 高度为40-60 µm，尖端直径约100 nm，并涂有脂质，以促进无缝穿透到膜中。 我们定制的制造阵列（电极螺距为20 µm），一旦将大脑表面放置在 穿透深度<60 µm的针头，并形成带有盘状树突分支的紧密电密封。读数将是 通过大量多路复用的低噪声定制CMOS放大器完成。证实两者的起源 平面表面记录和体内纳米树突记录，我们将结合常规的内部和 细胞外真正真实的电生理学，两光子钙成像，光遗传学，使用尖峰排序 模板匹配和晶须触摸。 最终，该平台不仅可以允许我们建立远端树突形状的计算规则 主动感觉期间的皮质输出，但提供了一种通用方法来探测生活中的树突整合 脑。