Myenteric Plexus

plexus myentericus Auerbachi

The myenteric plexus (Auerbach plexus) is one of the two main components of the enteric nervous system, located between the circular and longitudinal smooth muscle layers of the gastrointestinal tract from the oesophagus to the anus. It controls gastrointestinal motility (peristalsis), coordinating the propulsive movements of the gut independently of the central nervous system.

Region: Abdomen

Clinical Relevance

Clinical Notes

Degeneration or absence of the myenteric plexus underlies several important gastrointestinal conditions. Hirschsprung disease results from the congenital absence of myenteric (and submucosal) ganglia in the distal colon, producing functional obstruction. Achalasia results from selective loss of inhibitory neurons in the oesophageal myenteric plexus, causing failure of lower oesophageal sphincter relaxation. Diabetic gastroparesis reflects myenteric plexus neuropathy in the stomach. Chagas disease (Trypanosoma cruzi) destroys the myenteric plexus in the oesophagus and colon.

Pathology

Common Injuries & Conditions

Hirschsprung Disease from Myenteric Plexus Aganglionosis

Absence of myenteric ganglion cells in the terminal colon from failure of neural crest cell migration produces a narrowed aganglionic segment with a dilated proximal bowel (megacolon), presenting in neonates with failure to pass meconium; rectal biopsy confirming aganglionosis and pull-through surgery removing the aganglionic segment are the standard management.