Migrating motor complex explained

Migrating motor complex, also known as migrating myoelectric complex, migratory motor complex, migratory myoelectric complex and MMC, is a cyclic, recurring motility pattern that occurs in the stomach and small bowel during fasting; it is interrupted by feeding.[1] A pattern of electrical activity is also observed in the gastrointestinal tract in a regular cycle during this interdigestive period.

MMC was discovered and characterized in fasting dogs in 1969 by Dr. Joseph H. Szurszewski at the Mayo Clinic.[2] He also showed that this activity stops upon eating a meal, and suggested that it induces a motor activity that acts as an "interdigestive housekeeper" in the small intestine. These motor complexes trigger peristaltic waves, which facilitate transportation of indigestible substances such as bone, fiber, and foreign bodies from the stomach, through the small intestine, past the ileocecal sphincter, and into the colon. MMC activity varies widely across individuals and within an individual when measured on different days. The MMC occurs every 90–230 minutes during the interdigestive phase (i.e., between meals) and is responsible for the rumbling experienced when hungry.[3] [4] 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; an impairment to the MMC typically results in small intestinal bacterial overgrowth.[5]

Phases

The MMC originates mostly in the stomach—although ~25% will arise from the duodenum or proximal jejunum—and can travel to the distal end of the ileum.[6] They consist of four distinct phases:

Regulation

Movements of the small bowel are believed to be controlled by the central and enteric nervous systems, intestinal muscles, and numerous peptides and hormones. For example, the MMC is thought to be initiated by motilin, and it does not directly depend on extrinsic nerves.[7] Additionally, gastrin, insulin, cholecystokinin, glucagon, and secretin have been reported to disrupt the MMC.

Eating interrupts the MMC. For example, one study found that a continental breakfast of 450 Kcal causes the MMC to disappear for 213 ± 48 minutes.[8] The number of calories and nature of food determine the length of the disruption with fats causing a longer disruption than carbohydrates which in turn cause a longer disruption than protein.[9]

Most of the cleaning waves in the MMC happen at night while we are asleep. For many people this will be sufficient enough to help maintain a healthy, balanced environment in the digestive tract. For others, it may be beneficial to space out food intake to allow for a couple cleaning waves to occur between meals throughout the day as well.[10]

Impairment

Autoimmunity following infection by a pathogen producing CdtB, such as C. jejuni, may be the leading cause of MMC impairment.[11] Narcotics are also known to impair the MMC.[12] Stress has been shown to reduce MMC activity as well.[13]

Patients with SIBO and IBS have on average a third as many MMC phase III events with those events being roughly 30% shorter on average.[14]

Therapeutic stimuli

Drugs used to enhance gastrointestinal motility are generally referred to as prokinetics. Serotonin induces phase III of the MMC, and so serotonin receptor agonists are commonly administered as prokinetics.[15] Motilin administration causes phase III contractions, and so motilin agonists are another common prokinetic.[16]

Eradication of bacterial overgrowth has been shown to partially restore MMC activity.

An elemental diet has been hypothesized to partially restore MMC function.[17]

External links

Notes and References

  1. Deloose E, Janssen P, Depoortere I, Tack J. The migrating motor complex: control mechanisms and its role in health and disease. Nat Rev Gastroenterol Hepatol. 2012;9(5):271-285. Published 2012 Mar 27. doi:10.1038/nrgastro.2012.57
  2. Szurszewski. Joseph H.. 1969-12-01. A migrating electric complex of canine small intestine. American Journal of Physiology. Legacy Content. en. 217. 6. 1757–1763. 10.1152/ajplegacy.1969.217.6.1757. 0002-9513.
  3. Dooley CP, Di Lorenzo C, Valenzuela JE . Variability of migrating motor complex in humans . Digestive Diseases and Sciences . 37 . 5 . 723–8 . May 1992 . 1563314 . 10.1007/BF01296429 .
  4. Takahashi T . Mechanism of interdigestive migrating motor complex . Journal of Neurogastroenterology and Motility . 18 . 3 . 246–57 . July 2012 . 22837872 . 3400812 . 10.5056/jnm.2012.18.3.246 .
  5. Book: Hasler, William . Physiology of the Gastrointestinal Tract . vanc . 2006 . Fourth .
  6. Book: Walter F . Boron . Emile Louis Jean Baptiste . Boulpaep . vanc . Medical physiology : a cellular and molecular approach . 2012 . Saunders . Philadelphia, Pa. . 978-1-4377-1753-2 . Updated second .
  7. Poitras P, Peeters TL . Motilin . Current Opinion in Endocrinology, Diabetes and Obesity . 15 . 1 . 54–7 . February 2008 . 18185063 . 10.1097/MED.0b013e3282f370af .
  8. Vantrappen G, Janssens J, Hellemans J, Ghoos Y . The interdigestive motor complex of normal subjects and patients with bacterial overgrowth of the small intestine . The Journal of Clinical Investigation . 59 . 6 . 1158–66 . June 1977 . 864008 . 372329 . 10.1172/JCI108740 .
  9. Vantrappen G, Janssens J, Peeters TL . The migrating motor complex . The Medical Clinics of North America . 65 . 6 . 1311–29 . November 1981 . 7035768 . 10.1016/S0025-7125(16)31474-2 .
  10. Web site: Bloating, Gut Health, and the Migrating Motor Complex . 2022-07-19 . Synergy Nutrition . en.
  11. Pimentel M, Morales W, Pokkunuri V, Brikos C, Kim SM, Kim SE, Triantafyllou K, Weitsman S, Marsh Z, Marsh E, Chua KS, Srinivasan S, Barlow GM, Chang C . 6 . Autoimmunity Links Vinculin to the Pathophysiology of Chronic Functional Bowel Changes Following Campylobacter jejuni Infection in a Rat Model . Digestive Diseases and Sciences . 60 . 5 . 1195–205 . May 2015 . 25424202 . 10.1007/s10620-014-3435-5 .
  12. Kueppers PM, Miller TA, Chen CY, Smith GS, Rodriguez LF, Moody FG . Effect of total parenteral nutrition plus morphine on bacterial translocation in rats . en . Annals of Surgery . 217 . 3 . 286–92 . March 1993 . 8452407 . 1242782 . 10.1097/00000658-199303000-00011 .
  13. Kumar D, Wingate DL . The irritable bowel syndrome: a paroxysmal motor disorder . Lancet . 2 . 8462 . 973–7 . November 1985 . 2865504 . 10.1016/S0140-6736(85)90525-2 .
  14. Pimentel M, Soffer EE, Chow EJ, Kong Y, Lin HC . Lower frequency of MMC is found in IBS subjects with abnormal lactulose breath test, suggesting bacterial overgrowth . Digestive Diseases and Sciences . 47 . 12 . 2639–43 . December 2002 . 12498278 . 10.1023/A:1021039032413 .
  15. Lördal M, Hellström PM . 1998-04-15. Serotonin induces phase III of the MMC, VIA 5-HT3-receptors dependent on cholinergic mechanisms in the small intestine . Gastroenterology . 114 . A795 . 10.1016/S0016-5085(98)83246-0 . free .
  16. Janssens J, Vantrappen G, Peeters TL . The activity front of the migrating motor complex of the human stomach but not of the small intestine is motilin-dependent . Regulatory Peptides . 6 . 4 . 363–9 . August 1983 . 6635258 . 10.1016/0167-0115(83)90265-3 .
  17. Pimentel M, Constantino T, Kong Y, Bajwa M, Rezaei A, Park S . A 14-day elemental diet is highly effective in normalizing the lactulose breath test . Digestive Diseases and Sciences . 49 . 1 . 73–7 . January 2004 . 14992438 . 10.1023/B:DDAS.0000011605.43979.e1 .

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Migrating motor complex".

Except where otherwise indicated, Everything.Explained.Today is © Copyright 2009-2024, A B Cryer, All Rights Reserved. Cookie policy.