Treger Jeremy S, Priest Michael F, Iezzi Raymond, Bezanilla Francisco
Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois.
Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois; Committee on Neurobiology, University of Chicago, Chicago, Illinois.
Biophys J. 2014 Sep 16;107(6):L09-12. doi: 10.1016/j.bpj.2014.07.054.
Clinical methods used to assess the electrical activity of excitable cells are often limited by their poor spatial resolution or their invasiveness. One promising solution to this problem is to optically measure membrane potential using a voltage-sensitive dye, but thus far, none of these dyes have been available for human use. Here we report that indocyanine green (ICG), an infrared fluorescent dye with FDA approval as an intravenously administered contrast agent, is voltage-sensitive. The fluorescence of ICG can follow action potentials in artificial neurons and cultured rat neurons and cardiomyocytes. ICG also visualized electrical activity induced in living explants of rat brain. In humans, ICG labels excitable cells and is routinely visualized transdermally with high spatial resolution. As an infrared voltage-sensitive dye with a low toxicity profile that can be readily imaged in deep tissues, ICG may have significant utility for clinical and basic research applications previously intractable for potentiometric dyes.
用于评估可兴奋细胞电活动的临床方法常常受到空间分辨率差或具有侵入性的限制。解决这一问题的一个有前景的方法是使用电压敏感染料光学测量膜电位，但到目前为止，这些染料都尚未可供人类使用。在此我们报告，吲哚菁绿（ICG），一种经美国食品药品监督管理局批准作为静脉注射造影剂的红外荧光染料，是电压敏感的。ICG的荧光能够跟踪人工神经元以及培养的大鼠神经元和心肌细胞中的动作电位。ICG还能使大鼠脑活体组织外植体中诱导的电活动可视化。在人类中，ICG标记可兴奋细胞，并且常规地以高空间分辨率经皮可视化。作为一种具有低毒性特征且能在深部组织中轻松成像的红外电压敏感染料，ICG可能对先前电位染料难以处理的临床和基础研究应用具有重大用途。
