Overview of the Anatomy, Physiology, and Pharmacology of the Autonomic Nervous System

TLDR

The autonomic nervous system, comprising sympathetic, parasympathetic, and enteric divisions, regulates all non‑skeletal muscles to maintain homeostasis and is targeted by many drugs, toxins, and is implicated in neurological disorders. This review aims to provide a comprehensive overview of the anatomy, physiology, and pharmacology of the sympathetic and parasympathetic divisions of the ANS. The article synthesizes historical and current information on these divisions, offering a resource for learners to appreciate their roles in health and disease. Other resources for the enteric nervous system should be consulted, © 2016 American Physiological Society, Compr Physiol 6:1239‑1278.

Abstract

ABSTRACT Comprised of the sympathetic nervous system, parasympathetic nervous system, and enteric nervous system, the autonomic nervous system (ANS) provides the neural control of all parts of the body except for skeletal muscles. The ANS has the major responsibility to ensure that the physiological integrity of cells, tissues, and organs throughout the entire body is maintained (homeostasis) in the face of perturbations exerted by both the external and internal environments. Many commonly prescribed drugs, over‐the‐counter drugs, toxins, and toxicants function by altering transmission within the ANS. Autonomic dysfunction is a signature of many neurological diseases or disorders. Despite the physiological relevance of the ANS, most neuroscience textbooks offer very limited coverage of this portion of the nervous system. This review article provides both historical and current information about the anatomy, physiology, and pharmacology of the sympathetic and parasympathetic divisions of the ANS. The ultimate aim is for this article to be a valuable resource for those interested in learning the basics of these two components of the ANS and to appreciate its importance in both health and disease. Other resources should be consulted for a thorough understanding of the third division of the ANS, the enteric nervous system. © 2016 American Physiological Society. Compr Physiol 6:1239‐1278, 2016.