Enteric (myenteric) plexus - marker
Plexus entericus (myentericus)
NervousNervesAbdomen
- What it is
- A representative piece of the enteric nervous system: a net of small ganglia and fibre bundles lying between the muscle layers of the gut wall (myenteric plexus), with a finer submucosal plexus inside it. It runs continuously from the oesophagus to the anus; only a short segment is shown.
- Function
- The "second brain" of the gut: its roughly 500 million neurons coordinate peristalsis, secretion and local blood flow on their own, merely adjusted by vagal and sympathetic input.
- Size
- Ganglia 0.1-0.5 mm (enlarged here); network mesh a few millimetres
- Clinical note
- Congenital absence of these ganglia in the last part of the colon (Hirschsprung disease) leaves a segment that cannot relax, causing severe constipation in newborns.