Batabyal Subrata, Satpathy Sarmishtha, Bui Loan, Kim Young-Tae, Mohanty Samarendra, Bachoo Robert, Davé Digant P
Nanoscope Technologies, Arlington, TX, USA.
Equal Contribution.
Biomed Opt Express. 2017 Jul 19;8(8):3700-3713. doi: 10.1364/BOE.8.003700. eCollection 2017 Aug 1.
We describe an optical technique for label-free detection of the action potential in cultured mammalian neurons. Induced morphological changes due to action potential propagation in neurons are optically interrogated with a phase sensitive interferometric technique. Optical recordings composed of signal pulses mirror the electrical spike train activity of individual neurons in a network. The optical pulses are transient nanoscale oscillatory changes in the optical path length of varying peak magnitude and temporal width. Exogenous application of glutamate to cortical neuronal cultures produced coincident increase in the electrical and optical activity; both were blocked by application of a Na-channel blocker, Tetrodotoxin. The observed transient change in optical path length in a single optical pulse is primarily due to physical fluctuations of the neuronal cell membrane mediated by a yet unknown electromechanical transduction phenomenon. Our analysis suggests a traveling surface wave in the neuronal cell membrane is responsible for the measured optical signal pulses.
我们描述了一种用于无标记检测培养的哺乳动物神经元动作电位的光学技术。利用相位敏感干涉技术对神经元中动作电位传播引起的形态变化进行光学检测。由信号脉冲组成的光学记录反映了网络中单个神经元的电脉冲序列活动。光学脉冲是具有不同峰值幅度和时间宽度的光程长度的瞬态纳米级振荡变化。向皮质神经元培养物中外源性施加谷氨酸会导致电活动和光学活动同时增加；两者都被应用钠通道阻滞剂河豚毒素所阻断。在单个光学脉冲中观察到的光程长度的瞬态变化主要是由一种尚不清楚的机电转导现象介导的神经元细胞膜的物理波动引起的。我们的分析表明，神经元细胞膜中的行波表面波是所测量的光学信号脉冲的原因。
