Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia.
Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
Cold Spring Harb Protoc. 2024 Sep 3;2024(9):pdb.prot108418. doi: 10.1101/pdb.prot108418.
Sleep studies in rely mostly on behavioral read-outs to support molecular or circuit-level investigations in this model. Electrophysiology can provide an additional level of understanding in these studies to, for example, investigate changes in brain activity associated with sleep manipulations. In this protocol, we describe a procedure for performing multichannel local field potential (LFP) recordings in the fruit fly, with a flexible system that can be adapted to different experimental paradigms and situations. The approach uses electrodes containing multiple recording sites (16), allowing the acquisition of large amounts of neuronal activity data from a transect through the brain while flies are still able to sleep. The approach starts by tethering the fly, followed by positioning it on an air-supported ball. A multichannel silicon probe is then inserted laterally into the fly brain via one eye, allowing for recording of electrical signals from the retina through to the central brain. These recordings can be acquired under spontaneous conditions or in the presence of visual stimuli, and the minimal surgery promotes long-term recordings (e.g., overnight). Sleep and wake can be tracked using infrared cameras, which allow for the measurement of locomotive activity as well as microbehaviors such as proboscis extensions during sleep. The protocol has been optimized to promote subject survivability, which is an important factor when performing long-term (∼16-h) recordings. The approach described here uses specific recording probes, data acquisition devices, and analysis tools. Although it is expected that some of these items might need to be adapted to the equipment available in different laboratories, the overall aim is to provide an overview on how to record electrical activity across the brain of behaving (and sleeping) flies using this kind of approach and technology.
在这个模型中，依赖行为读数来支持分子或电路水平研究的睡眠研究。电生理学可以为这些研究提供额外的理解水平，例如，研究与睡眠操作相关的大脑活动变化。在本协议中，我们描述了一种在果蝇中进行多通道局部场电位 (LFP) 记录的程序，该程序具有灵活的系统，可以适应不同的实验范式和情况。该方法使用包含多个记录位点的电极（16），允许在苍蝇仍能睡眠的情况下，从大脑中的横切面上获取大量神经元活动数据。该方法首先将苍蝇系绳，然后将其定位在空气支撑的球上。然后，通过一只眼睛将多通道硅探针侧向插入苍蝇大脑，从而可以从视网膜记录到中央大脑的电信号。可以在自发条件下或存在视觉刺激下获取这些记录，并且最小的手术促进长期记录（例如，过夜）。可以使用红外摄像机跟踪睡眠和清醒状态，这允许测量运动活动以及睡眠期间的触角延伸等微观行为。该协议已进行优化以提高实验动物的存活率，这是进行长期（约 16 小时）记录的重要因素。这里描述的方法使用特定的记录探针、数据采集设备和分析工具。尽管预计其中一些项目可能需要适应不同实验室可用的设备，但总体目标是提供如何使用这种方法和技术记录行为（和睡眠）苍蝇大脑中的电活动的概述。
