Enteric nervous system: sensory transduction, neural circuits and gastrointestinal motility

Nat Rev Gastroenterol Hepatol. 2020 Jun;17(6):338-351. doi: 10.1038/s41575-020-0271-2. Epub 2020 Mar 9.

Abstract

The gastrointestinal tract is the only internal organ to have evolved with its own independent nervous system, known as the enteric nervous system (ENS). This Review provides an update on advances that have been made in our understanding of how neurons within the ENS coordinate sensory and motor functions. Understanding this function is critical for determining how deficits in neurogenic motor patterns arise. Knowledge of how distension or chemical stimulation of the bowel evokes sensory responses in the ENS and central nervous system have progressed, including critical elements that underlie the mechanotransduction of distension-evoked colonic peristalsis. Contrary to original thought, evidence suggests that mucosal serotonin is not required for peristalsis or colonic migrating motor complexes, although it can modulate their characteristics. Chemosensory stimuli applied to the lumen can release substances from enteroendocrine cells, which could subsequently modulate ENS activity. Advances have been made in optogenetic technologies, such that specific neurochemical classes of enteric neurons can be stimulated. A major focus of this Review will be the latest advances in our understanding of how intrinsic sensory neurons in the ENS detect and respond to sensory stimuli and how these mechanisms differ from extrinsic sensory nerve endings in the gut that underlie the gut-brain axis.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Afferent Pathways / physiology
  • Autonomic Fibers, Preganglionic / physiology
  • Efferent Pathways / physiology
  • Enteric Nervous System / metabolism
  • Enteric Nervous System / physiology*
  • Enteroendocrine Cells / metabolism
  • Enteroendocrine Cells / physiology
  • Gastrointestinal Motility / physiology*
  • Humans
  • Mechanotransduction, Cellular / physiology
  • Myoelectric Complex, Migrating / physiology
  • Neural Pathways / physiology
  • Neurons / metabolism
  • Neurons / physiology
  • Neurotransmitter Agents / metabolism
  • Sensation / physiology*
  • Sensory Receptor Cells / metabolism
  • Sensory Receptor Cells / physiology*
  • Serotonin / metabolism

Substances

  • Neurotransmitter Agents
  • Serotonin