Giardini Francesco, Biasci Valentina, Scardigli Marina, Pavone Francesco S, Bub Gil, Sacconi Leonardo
European Laboratory for Non-Linear Spectroscopy, 50019 Sesto Fiorentino, Italy.
Division of Physiology, Department of Experimental and Clinical Medicine, University of Florence, 50134 Florence, Italy.
Methods Protoc. 2019 Jan 8;2(1):7. doi: 10.3390/mps2010007.
Optogenetics is an emerging method that uses light to manipulate electrical activity in excitable cells exploiting the interaction between light and light-sensitive depolarizing ion channels, such as channelrhodopsin-2 (ChR2). Initially used in the neuroscience, it has been adopted in cardiac research where the expression of ChR2 in cardiac preparations allows optical pacing, resynchronization and defibrillation. Recently, optogenetics has been leveraged to manipulate cardiac electrical activity in the intact heart in real-time. This new approach was applied to simulate a re-entrant circuit across the ventricle. In this technical note, we describe the development and the implementation of a new software package for real-time optogenetic intervention. The package consists of a single LabVIEW program that simultaneously captures images at very high frame rates and delivers precisely timed optogenetic stimuli based on the content of the images. The software implementation guarantees closed-loop optical manipulation at high temporal resolution by processing the raw data in workstation memory. We demonstrate that this strategy allows the simulation of a ventricular tachycardia with high stability and with a negligible loss of data with a temporal resolution of up to 1 ms.
光遗传学是一种新兴方法，它利用光与光敏去极化离子通道（如通道视紫红质-2，ChR2）之间的相互作用，通过光来操纵可兴奋细胞中的电活动。该方法最初用于神经科学领域，现已应用于心脏研究，在心脏制剂中ChR2的表达可实现光学起搏、再同步化和除颤。最近，光遗传学已被用于实时操纵完整心脏中的心脏电活动。这种新方法被应用于模拟跨心室的折返环路。在本技术说明中，我们描述了一种用于实时光遗传学干预的新软件包的开发和实施。该软件包由一个单一的LabVIEW程序组成，该程序以非常高的帧率同时捕获图像，并根据图像内容提供精确计时的光遗传学刺激。通过在工作站内存中处理原始数据，软件实现保证了在高时间分辨率下的闭环光学操纵。我们证明，这种策略能够以高达1毫秒的时间分辨率，高度稳定地模拟室性心动过速，且数据丢失可忽略不计。
