Muscularis externa

(Redirected from Tunica muscularis)
Jump to navigation Jump to search

Template:Infobox Anatomy Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]


The muscular coat (or muscular layer, or muscular fibers, or muscularis propria, or muscularis externa) is a region of muscle in many organs in the vertebrate body, adjacent to the mucous membrane. It is responsible for gut movement such as peristalsis.

It usually has two distinct layers of smooth muscle:

  • inner and "circular"
  • outer and "longitudinal"

However, there are some exceptions to this pattern.

  • In the stomach, there are three layers to the muscularis externa.
  • In the upper esophagus, part of the externa is skeletal muscle, rather than smooth muscle.

The inner layer of the muscularis externa forms a sphincter at two locations of the alimentary canal:

Additional images

External links

Template:Gray's Template:TissueLayers

Template:WikiDoc Sources