Feasibility and effectiveness of transcutaneous auricular vagus nerve stimulation (taVNS) in awake mice.

Aims: Transcutaneous auricular vagus nerve stimulation (taVNS) is widely used to treat a variety of disorders because it is noninvasive, safe, and well tolerated by awake patients. However, long-term and repetitive taVNS is difficult to achieve in awake mice. Therefore, developing a new taVNS method that fully mimics the method used in clinical settings and is well-tolerated by awake mice is greatly important for generalizing research findings related to the effects of taVNS. The study aimed to develop a new taVNS device for use in awake mice and to test its reliability and effectiveness.
Methods: We demonstrated the reliability of this taVNS device through retrograde neurotropic pseudorabies virus (PRV) tracing and evaluated its effectiveness through morphological analysis. After 3 weeks of taVNS application, the open field test (OFT) and elevated plus maze (EPM) were used to evaluate anxiety-like behaviors, and the Y-maze test and novel object recognition test (NORT) were used to evaluate recognition memory behaviors, respectively.
Results: We found that repetitive taVNS was well tolerated by awake mice, had no effect on anxiety-like behaviors, and significantly improved memory.
Conclusion: Our findings suggest that this new taVNS device for repetitive stimulation of awake mice is safe, tolerable, and effective.
(© 2024 The Author(s). CNS Neuroscience & Therapeutics published by John Wiley & Sons Ltd.)