Migrating Motor Complex
Encyclopedia
Migrating motor complexes (or migrating myoelectric complex) are waves of activity that sweep through the intestines in a regular cycle during fasting state.
These motor complexes help trigger peristaltic wave
s which facilitate transportation of indigestible substances such as bone, fiber and foreign bodies from the stomach
, through the small intestine
past the ileocecal sphincter into the colon
.
The MMC originates in the stomach roughly every 75–90 minutes during the interdigestive phase (between meals) and is responsible for the rumbling
experienced when hungry.
It also serves to transport bacteria
from the small intestine
to the large intestine
, and to inhibit the migration of colonic bacteria into the terminal ileum.
The MMC is thought to be partially regulated by motilin
which is initiated in the stomach as a response to vagal
stimulation, and does not depend on extrinsic nerves directly.
These motor complexes help trigger peristaltic wave
Peristalsis
Peristalsis is a radially symmetrical contraction and relaxation of muscles which propagates in a wave down the muscular tube, in an anterograde fashion. In humans, peristalsis is found in the contraction of smooth muscles to propel contents through the digestive tract. Earthworms use a similar...
s which facilitate transportation of indigestible substances such as bone, fiber and foreign bodies from the stomach
Stomach
The stomach is a muscular, hollow, dilated part of the alimentary canal which functions as an important organ of the digestive tract in some animals, including vertebrates, echinoderms, insects , and molluscs. It is involved in the second phase of digestion, following mastication .The stomach is...
, through the small intestine
Small intestine
The small intestine is the part of the gastrointestinal tract following the stomach and followed by the large intestine, and is where much of the digestion and absorption of food takes place. In invertebrates such as worms, the terms "gastrointestinal tract" and "large intestine" are often used to...
past the ileocecal sphincter into the colon
Colon (anatomy)
The colon is the last part of the digestive system in most vertebrates; it extracts water and salt from solid wastes before they are eliminated from the body, and is the site in which flora-aided fermentation of unabsorbed material occurs. Unlike the small intestine, the colon does not play a...
.
The MMC originates in the stomach roughly every 75–90 minutes during the interdigestive phase (between meals) and is responsible for the rumbling
Borborygmus
Borborygmus also known as stomach growling, rumbling, gurgling, grumbling or wambling, is the rumbling sound produced by the contraction of muscles in the stomach and intestines of animals, including humans...
experienced when hungry.
It also serves to transport bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
from the small intestine
Small intestine
The small intestine is the part of the gastrointestinal tract following the stomach and followed by the large intestine, and is where much of the digestion and absorption of food takes place. In invertebrates such as worms, the terms "gastrointestinal tract" and "large intestine" are often used to...
to the large intestine
Large intestine
The large intestine is the third-to-last part of the digestive system — — in vertebrate animals. Its function is to absorb water from the remaining indigestible food matter, and then to pass useless waste material from the body...
, and to inhibit the migration of colonic bacteria into the terminal ileum.
The MMC is thought to be partially regulated by motilin
Motilin
Motilin is a 22-amino acid polypeptide hormone in the motilin family that, in humans, is encoded by the MLN gene.Motilin is secreted by endocrine M cells that are numerous in crypts of the small intestine, especially in the duodenum and jejunum. Based on amino acid sequence, motilin is unrelated...
which is initiated in the stomach as a response to vagal
Vagus nerve
The vagus nerve , also called pneumogastric nerve or cranial nerve X, is the tenth of twelve paired cranial nerves...
stimulation, and does not depend on extrinsic nerves directly.