ZFIN ID: ZDB-PUB-150717-5
Zebrafish Needle EMG: a New Tool for High-throughput Drug Screens
Cho, S.J., Nam, T.S., Byun, D., Choi, S.Y., Kim, M.K., Kim, S.
Date: 2015
Source: Journal of neurophysiology   114(3): 2065-70 (Journal)
Registered Authors: Choi, Seok-Yong
Keywords: electrode, microneedle, motor unit action potential (MUAP), needle electromyography (EMG), zebrafish
MeSH Terms:
  • Action Potentials
  • Animals
  • Drug Discovery/methods
  • Electrodes
  • Electromyography/instrumentation
  • Electromyography/methods*
  • High-Throughput Screening Assays/instrumentation
  • High-Throughput Screening Assays/methods*
  • Muscle, Skeletal/physiology
  • Zebrafish
PubMed: 26180124 Full text @ J. Neurophysiol.
Zebrafish models have recently been highlighted as a valuable tool in studying the molecular basis of neuromuscular diseases and developing new pharmacological treatments. Needle electromyography (EMG) is needed not only for validating transgenic zebrafish models with muscular dystrophies (MD), but also for assessing the efficacy of therapeutics. However, performing needle EMG on larval zebrafish has not been feasible due to the lack of proper EMG sensors and systems for such small animals. We introduce a new type of EMG needle electrode to measure intramuscular activities of larval zebrafish, together with a method to hold the animal in position during EMG, without anesthetization. The silicon-based needle electrode was found to be sufficiently strong and sharp to penetrate the skin and muscles of zebrafish larvae, and its shape and performance did not change after multiple insertions. Using the proposed needle electrode and measurement system, EMG was successfully performed on zebrafish at 30 days post fertilization (dpf) and at 5 dpf. Burst patterns and spike morphology of the recorded EMG signals were analyzed. The measured single spikes were triphasic with an initial positive deflection, which is typical for motor unit action potentials, with durations of approximately 10 ms, while the muscle activity was silent during the anesthetized condition. These findings confirmed the capability of this system of detecting EMG signals from very small animals such as 5 dpf zebrafish. The developed EMG sensor and system are expected to become a helpful tool in validating zebrafish MD models and further developing therapeutics.