Holmes Taylor C, Penaloza-Aponte Jesus D, Mickle Alyssa R, Nosacka Rachel L, Dale Erica A, Streeter Kristi A
Exercise and Rehabilitation Science Program, Department of Physical Therapy, Marquette University, Milwaukee, Wisconsin 53233.
Department of Neuroscience, University of Florida, Gainesville, Florida 32610.
eNeuro. 2025 Feb 19;12(2). doi: 10.1523/ENEURO.0444-24.2025. Print 2025 Feb.
Breathing is a complex neuromuscular process vital to sustain life. In preclinical animal models, the study of respiratory motor control is primarily accomplished through neurophysiologic recordings and functional measurements of respiratory output. Neurophysiologic recordings that target neural or muscular output via direct nerve recordings or respiratory muscle electromyography (EMG) are commonly collected during anesthetized conditions. While offering tight control of experimental preparations, the use of anesthesia results in respiratory depression, may impact cardiovascular control, eliminates the potential to record volitional nonventilatory behaviors, and can limit translation. Since the diaphragm is a unique muscle which is rhythmically active and difficult to access, placing diaphragm EMGs to collect chronic recordings in awake animals is technically challenging. Here, we describe methods for fabricating and implanting indwelling diaphragm EMG electrodes to enable recordings from awake rodents for longitudinal studies. These electrodes are relatively easy and quick to produce (∼1 h), are affordable, and provide high-quality and reproducible diaphragm signals using a tethered system that allows animals to behave. This system is also designed to work in conjunction with whole-body plethysmography to facilitate simultaneous recordings of diaphragm EMG and ventilation. We include detailed instructions and considerations for electrode fabrication and surgical implantation. We also provide a brief discussion on data acquisition, material considerations for implant fabrication, and the physiological implications of the diaphragm EMG signal.
呼吸是维持生命至关重要的复杂神经肌肉过程。在临床前动物模型中,呼吸运动控制的研究主要通过神经生理学记录和呼吸输出的功能测量来完成。通过直接神经记录或呼吸肌肌电图(EMG)针对神经或肌肉输出的神经生理学记录通常在麻醉状态下收集。虽然麻醉能对实验准备进行严格控制,但使用麻醉会导致呼吸抑制,可能影响心血管控制,消除记录自主非通气行为的可能性,并且会限制研究成果的转化。由于膈肌是一块独特的肌肉,有节律地活动且难以触及,在清醒动物身上放置膈肌EMG电极以收集长期记录在技术上具有挑战性。在此,我们描述了制造和植入留置膈肌EMG电极的方法,以便能够从清醒啮齿动物身上进行记录用于纵向研究。这些电极相对容易且快速制作(约1小时),成本低廉,并使用允许动物活动的系留系统提供高质量且可重复的膈肌信号。该系统还设计为与全身体积描记法协同工作,以促进膈肌EMG和通气的同步记录。我们包括了电极制作和手术植入的详细说明及注意事项。我们还简要讨论了数据采集、植入物制作的材料考虑以及膈肌EMG信号的生理意义。