Migrating motor complexes

S. K. Sarna. Cyclic motor activity migrating motor complex. Gastroenterol. 1985, 89, 894-913. 

Shindo et al. [66] treated 19 healthy volunteers with omeprazole 20 mg, cultured gastric and jejunal aspirate, and determined gastric pH and bile acid metabolism. Although motility studies were not performed, it can be assumed that intestinal migrating motor complexes were normal [21] (fig. 4). Bacterial colonization was defined by species density exceeding 105 CFU/0.5 ml, and only reported for those exceeding this limit. 

Fig. 4. The normal nocturnal migrating motor complex (MMC) recorded in the duodenum (upper tracing) and proximal jejunum (lower tracing) of a 91-year-old healthy woman. A short period is shown in high resolution in the lower panel. Phase III is preceded by phase II with some contractile activity, usually limited during sleep, and succeeded by contractile quiescence, phase I. The sequence of phase III-I-II-III constitutes one MMC cycle, and recurs during fasting (modified with permission from Husebye and Engedal [79]).

Fig. 5. Relationship between fasting intestinal motility [x-axis migrating motor complex (MMC) index] and bacterial colonization of small bowel in 41 patients with late radiation enteropathy (LRE) is shown by two plots. Relationship to Gram-negative bacilli (a) and to total bacterial count (b) in the duodenum is shown. Note that no significant Gram-negative colonization was found in patients with normal MMC (index = 3). The vertical dotted lines show the normal limit for MMC index. Increased bacterial counts due to URT flora were found in some patients with normal MMC (b). Tied observations are indicated as follows n = 1 n = 2 1 n = 3 1 n = 4 + n = 6 For n > 6...

Intestinal mechanical clearance thus consists of both reflex-mediated contractions (peristalsis) elicited by the stimulatory effect of luminal contents and of periods of spontaneous contractile activity (e.g. the migrating motor complex). During fasting about 50% of intestinal transit has been attributed to phase III of the migrating motor complex, the remaining mostly to the propulsive contractions and motor patterns during phase II [ 108]. Luminal flow can also occur in the absence of propagating contractions of the circular muscle layer, so far considered the motor event mainly responsible for flow in the small intestine. 

Studies of small bowel transit time have demonstrated a great variability both within and between individuals. When the hydrogen breath test was performed under fasting conditions, using 10 ml of lactulose, the coefficient of variation amounted to 18%. Di Lorenzo et al. [129] showed that variations under fasting conditions are partly accounted for by the phase of the migrating motor complex at the intake of test solution. Moreover, when a lactose-containing meal was used, the coefficient of variation was reduced to 4% [130],... 

Chagas disease affects enteric ganglionic cells. This leads to altered motility with a reduced rate of migration for the migrating motor complex [165], a change associated with colonization with Gram-negative bacilli [12]. 

Patients with advances liver cirrhosis often suffer from bacterial overgrowth [175], Chang et al. [176] reported a reduced frequency and rate of migration for migrating motor complexes in patients with liver cirrhosis, alterations that predispose to colonization of the small bowel by Gram-negative bacilli [12],... 

Yantrappen et al. [23] for the first time showed the relevance of phase III of the migrating motor complex in the current context, when reporting its absence in 5 of 12 patients with bacterial overgrowth detected by the bile acid breath test and response to antibiotics. 

Vantrappen G, Peeters TL, Janssens J The secretory component of the interdigestive migrating motor complex in man. Scand J Gastroenterol 1979 14 663-667. 

Kumar D, Wingate D, Ruckebusch Y. Circadian variation in the propagation velocity of the migrating motor complex. Gastroenterology 1986 91 926-930. 

Macrolide antibiotics such as erythromycin directly stimulate motilin receptors on gastrointestinal smooth muscle and promote the onset of a migrating motor complex. Intravenous erythromycin (3 mg/kg) is beneficial in some patients with gastroparesis however, tolerance rapidly develops. It may be used in patients with acute upper gastrointestinal hemorrhage to promote gastric emptying of blood before endoscopy. 

Sama, S.K. 1985. Cyclic motor activity Migrating motor complex. Gastroenterology 89 894. 

Schemann, M., and H.J. Ehrlein. 1986. Mechanical characteristics of phase II and phase III of the interdigestive migrating motor complex in dogs. Gastroenterology 91 117. 

Motilin Motilin receptor 22-residue peptide Stimulate migrating motor complex Solid-phase V"-Boc chemistry... 

Motilin is a 22-amino acid peptide first isolated from hog duodenal mucosa by Brown and colleagues in 1972 (18, 19). It was found to be released from endocrine cells of the duodenal-jejunal mucosa to control gastrointestinal muscles by controlling the migrating motor complex. 

Phase 3 A short burst of intense contractions that are propagated distally from the stomach to the terminal ileum. These have been termed migrating motor complexes (MMCs), or "housekeeper waves." Phase 4 A short period of transition with diminished contractile activity. 

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