Circular muscular layer of small intestine
Stratum musculare circulare intestini tenuis
- Latin synonym: Stratum circulare tunicae muscularis intestini tenuis; Stratum helicoideum gradus brevis
- Synonym: Circular layer of muscular coat of small intestine; Short pitch helicoidal layer
- Related terms: Circular layer; Short pitch helicoidal layer
Definition
The muscular coat (tunica muscularis) consists of two layers of unstriped fibers: an external, longitudinal, and an internal, circular layer.
The longitudinal fibers are thinly scattered over the surface of the intestine, and are more distinct along its free border.
The circular fibers form a thick, uniform layer, and are composed of plain muscle cells of considerable length.
The muscular coat is thicker at the upper than at the lower part of the small intestine.
References
This definition incorporates text from a public domain edition of Gray's Anatomy (20th U.S. edition of Gray's Anatomy of the Human Body, published in 1918 – from http://www.bartleby.com/107/).
