The migrating motor complex is a distinct pattern of electromechanical activity observed in the gastrointestinal tract during periods of fasting. It consists of 4 phases and recurs every 1.5 to 2 hours. Phase 1 involves smooth muscle inactivity. Phase 2 involves increasing peristaltic contractions originating in the stomach. Phase 3 involves rapid, evenly spaced peristaltic contractions that allow undigested material to pass into the small intestine. Phase 4 is a transition period between phases 3 and 1. The migrating motor complex sweeps excess secretions and residual materials into the colon to prevent bacterial buildup and provide a cleansing function in the gastrointestinal tract.

1. MIGRATINGMOTOR COMPLEX
Saleem.Sayed,
Nimra institute of medical sciences.

2. What is migrating motor complex ?
■ Migrating motor complex is a distinct pattern of electromechanical activity.
■ It is observed in gastrointestinal smooth muscle during the periods between
meals.(during the periods of fasting for several hours)
■ A large portion of stomach or intestine is involved in the contraction.
■ It serves a "housekeeping" role and sweep residual undigested materials.
■ The cycle recurs every 1.5 to 2 hours and consists of 4 phases:

3. 4 phases of MMC
1. A period of smooth muscle inactivity lasting 45 to 60 minutes.(there are only
action potentials and contractions.)
2. A period of 30 minutes in which peristaltic contractions occur and progressively
and increase in frequency. (Peristalsis originates in the stomach and propagates
through the small intestine.)
3. A phase lasting 5 to 15 minutes in which, rapid & evenly spaced peristaltic
contractions occur. (The pylorus remains open and allows indigestible materials
to pass into the small intestine.)
4. A period of transition between the contractions in phase 3 and the inactivity of
phase 1.

5. ■ An increase in gastric, biliary and pancreatic secretion is also seen in
along with the motor activity.
■ It helps in the cleansing activity of the MMC and prevents building up of
bacterial populations in the proximal segments.
■ It is thought to be controlled from the central nervous system(CNS) and
may be implemented by enteric hormone ”motilin”.

6. Roles of Migrating Motor Complex
■ It sweeps the excess digestive secretions into the colon & prevents the
accumulation of the secretions in stomach and intestine.
■ It also sweeps the residual indigested materials into colon.
■ Migrating motor complex has potentially important therapeutic and social
implications.
■ Migrating motor complexes can be noisy and are the cause of "growling.”
■ Ingestion of food will abolish a MMC and restore a digestive pattern of motility.

8. THANK YOU