Myenteric

Myenteric is an adjective relating to the myenteron, the embryonic gut tube, and is most commonly used in reference to the myenteric plexus of the enteric nervous system. The term is most often encountered in description of the myenteric plexus, also called Auerbach's plexus, a network of neurons and glial cells located between the circular and longitudinal layers of the gastrointestinal tract wall from the esophagus to the internal anal sphincter.

The myenteric plexus forms part of the enteric nervous system, together with the submucosal (Meissner's) plexus. It primarily coordinates motor activity, controlling peristalsis and the tone of smooth muscle, and modulates propulsion and mixing through local reflex circuits. Sensory input from the mucosa informs this network, which communicates with smooth muscle to regulate rhythmic contractions.

Developmentally, enteric neurons originate from neural crest cells that migrate into the gut wall. Proper formation of the myenteric plexus is essential for coordinated gut motility; disruptions can lead to dysmotility or functional impairment of intestinal propulsion.

Clinical significance includes various motility disorders associated with myenteric dysfunction. In Hirschsprung disease, there is congenital absence of ganglion cells in the distal colon’s myenteric and submucosal plexuses, resulting in a functional obstruction and chronic constipation. Treatment typically involves surgical resection of the aganglionic segment. The myenteric plexus remains a focus of study in conditions affecting gut motility and aging.