MH 109 Esophagus

Parasympathetic Ganglion

Parasympathetic ganglia are part of the autonomic nervous system. Most are small ganglia located near or within the organs they innervate.

The outer wall of the esophagus (muscularis externa) is composed of two layers of muscle tissue.

• Inner Layer - a circular layer of muscle cells
• Outer Layer - a longitudinal layer of muscle cells

Motor innervation is provided by a network of small ganglia connected by nerves (plexus) located between the muscle layers known as Auerbach's (or myenteric) plexus. It is found in the esophagus, stomach, and intestines.

Parasympathetic ganglia of Auerbach's plexus are very small and usually contain less than five nerve cell bodies.

• Ganglion Cells - large, nerve cell bodies with prominent nuclei and nucleoli with a basophilic cytoplasm. Unlike sympathetic ganglia, nuclei are eccentrically located within the cells.
• Satellite Cells (or capsule cells) - glial cells with small nuclei at the periphery of nerve cell bodies.
• Nerves - are seen in cross-section as bundles between individual ganglia.

Examples of adjacent ganglia in the plexus: #1,#2,#3,#4,#5, #6 , #7 , and  #8 .