Review Article

Vagus Nerve and Vagus Nerve Stimulation, a Comprehensive Review: Part I

Hsiangkuo Yuan MD, PhD

Hsiangkuo Yuan MD, PhD

Jefferson Headache Center, Thomas Jefferson University, Philadelphia, PA, USA

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Stephen D. Silberstein MD

Corresponding Author

Stephen D. Silberstein MD

Jefferson Headache Center, Thomas Jefferson University, Philadelphia, PA, USA

Address all correspondence to S.D. Silberstein, MD, FACP, Jefferson Headache Center, Thomas Jefferson University, 900 Walnut Street, Suite 200, Philadelphia, PA 19107, USA, email: [email protected]Search for more papers by this author
First published: 14 September 2015
Citations: 203

Conflict of Interest: Dr. Yuan serves as a consultant for Supernus Pharmaceuticals, Inc., as a consultant and/or advisory panel member. Dr. - Silberstein receives honoraria from Alder Biopharmaceuticals, Allergan, Inc., Amgen, Avanir Pharmaceuticals, Inc., Depomed, Dr. Reddy's Laboratories, eNeura Inc., electroCore Medical, LLC, Ipsen Biopharmaceuticals, Medscape, LLC, Medtronic, Inc., Mitsubishi Tanabe Pharma America, Inc., NINDS, St. Jude Medical, Supernus Pharmaceuticals, Inc., Teva Pharmaceuticals, and Trigemina, Inc.

Abstract

The vagus nerve (VN), the “great wondering protector” of the body, comprises an intricate neuro-endocrine-immune network that maintains homeostasis. With reciprocal neural connections to multiple brain regions, the VN serves as a control center that integrates interoceptive information and responds with appropriate adaptive modulatory feedbacks. While most VN fibers are unmyelinated C-fibers from the visceral organs, myelinated A- and B-fiber play an important role in somatic sensory, motor, and parasympathetic innervation. VN fibers are primarily cholinergic but other noncholinergic nonadrenergic neurotransmitters are also involved. VN has four vagal nuclei that provide critical controls to the cardiovascular, respiratory, and alimentary systems. Latest studies revealed that VN is also involved in inflammation, mood, and pain regulation, all of which can be potentially modulated by vagus nerve stimulation (VNS). With a broad vagal neural network, VNS may exert a neuromodulatory effect to activate certain innate “protective” pathways for restoring health.