PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Myoelectric Complex, Migrating”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 469 records · Page 26Linked to original sources

Intermittent bursts of motor activity in the human rectum and absence of propagation.

Manometric recordings from multiple sites were performed to determine the propagating properties of intermittent bursts of motor activity in the human rectum. Pressure changes were recorded simultaneously at 12.5 cm, 10 cm and 7.5 cm from the anal verge in nine healthy subjects for a total recording time of 32 hours, each study lasting 2.7-4.8 hours. The burst motor activity was identified on 19 occasions in 7 of 9 subjects at 12.5 cm; 26 occasions in all subjects at 10 cm; and 11 occasions in 3 of 9 subjects at 7.5 cm. In most cases, the burst motor activity was observed at a single recording site while other recording sites were quiescent. It did not appear to migrate in either an oral or aboral direction. The burst motor activity contained in part runs of pressure waves with a regular frequency: at 12.5 and 10 cm of the recording site, runs of regular pressure waves were dominated by a frequency of 2.5-5 cycle per minute, whereas those at 7.5 cm occurred with a higher frequency and a lower amplitude as compared with the more proximal recording sites. No evidence of propagation of each pressure wave was seen even when the burst occurred simultaneously at more than two recording sites. These results suggest that the intermittent bursts of rectal motor activity occur locally and do not propagate in either on oral or aboral direction. They appear dissimilar to the interdigestive migrating motor complex observed in the more proximal part of the gut.

Adult↗

Pancreaticobiliary juice releases motilin during phase I of the migrating motor complex in man.

The effect of duodenal perfusion with pancreaticobiliary juice on plasma motilin was investigated in eight fasting subjects. The study was undertaken with recording of gastrointestinal motility, to predict spontaneous fluctuations in plasma motilin levels. Duodenal perfusion with pancreaticobiliary juice or saline at a rate of 5 ml/min for 10 min was performed in random order after the second or third activity front. The 30-min integrated plasma motilin response was significantly greater after perfusion with pancreaticobiliary juice: 1.5 (0.7-2.3) nmol x min/l (mean and 95% confidence interval), compared with 1.0 (0.5-1.5) nmol x min/l after saline (p < 0.05). Although perfusion with pancreaticobiliary juice was followed by endogenous plasma motilin peaks after about 20 min in six of eight subjects, the mean interval to the next activity front was not significantly different. In conclusion, duodenal perfusion with pancreaticobiliary juice in phase I of the migrating motor complex releases plasma motilin without affecting the fasting motility pattern.

Adult↗

Opioid-induction of migrating motor activity in chickens.

Enkephalin and morphine initiation of phase III of MMC has been reported in dog and humans. In chickens, a similar migrating activity initiated at the duodenum occurs 7-9 times a day while the gastric activity ceases. The main objective was to determine whether this migrating activity could be induced by opioids. Electrodes for electromyography were implanted in the stomach, proximal and distal duodenum, jejunum and proximal and distal ileum of 4 wk old chickens. Met-enkephalin, morphine and beta-casomorphin-5 (5 x 10(-7) moles/Kg) were infused i.v.. All these substances initiated an intestinal migrating activity concurrent with gastric inhibition. The mean duration of gastric inhibition depended on the substance, lasting from 5 min (met-enkephalin) to 27 min (beta-casomorphin-5). The migrating activity started in the distal duodenum and propagated to the ileum in about 18 min. These effects were partially blocked by naloxone at equimolar doses. In conclusion, in chickens, as in dogs and humans, migrating myoelectrical activity can be initiated by opioids.

Animals↗

Resulting long-term intestinal motility in dogs following construction of a reversed jejunal segment after extensive small bowel resection.

To evaluate the long-term function and effective motility of a reversed jejunal segment after extensive small bowel resection, the authors continuously measured postoperative bowel motility during interdigestive and postprandial periods in conscious dogs 6 to 10 months after surgery. The long-term findings were compared with previously reported short-term results measured 2 to 4 weeks after the operation. In the long-term follow-up dogs with a 20-cm reversed jejunal segment constructed after extensive (75% to 80%) small bowel resection, the fasting duodenal migrating myoelectric (or motor) complex (MMC) was often interrupted in the jejunum above the reversed segment, and did not migrate smoothly to the reversed segment or terminal ileum. The MMCs arising from the duodenum predominantly propagated to the ileum through the inherent anatomic continuity of the bowel. In addition, brief small discordant contractions were frequent in the reversed segment and the jejunum, above the proximal anastomosis. These findings are similar to those of the MMC propagation pattern noted 2 to 4 weeks after surgery. However, the postprandial duration without duodenal MMC activity was significantly shorter in the dogs with long-term follow-up than in those with short-term follow-up (both were longer than in control dogs). Marked dilatation of the jejunum and reversed jejunal segment was noted across the proximal anastomosis. These results suggest that the transit time and passage of intestinal contents can be delayed and stagnated for at least 10 months after extensive small bowel resection with a 20-cm reversed jejunal segment.(ABSTRACT TRUNCATED AT 250 WORDS)

Anastomosis, Surgical↗

Bursts of non-deglutitive simultaneous contractions may be a normal oesophageal motility pattern.

The frequency and characteristics of non-deglutitive motor activity of the human oesophagus and its relation to motility patterns in the antrum and upper small intestine were studied in 25 fasted healthy subjects. Motility of the oesophagus, antrum, and upper small intestine was recorded by means of a manometric perfused catheter system. The most striking non-deglutitive motility pattern consisted of repetitive bursts of non-sequential pressure peaks occurring in the smooth muscle portion of the oesophagus. The mean number of pressure peaks per burst was 2.7 (SD 2) waves with a mean amplitude of 19.5 (SD 9.9) mm Hg and a duration of 3.09 (SD 0.22) seconds. The highest amplitude was 80 mm Hg and the longest burst consisted of 13 repetitive waves. The bursts were recorded up to a distance of 15-20 cm above the lower oesophageal sphincter. Ninety five per cent of the bursts occurred during a 15 minute period before the onset of phase 3 of the migrating motor complex in the antral or upper small intestinal area, or during the lower oesophageal sphincter component of the migrating motor complex. In conclusion, spontaneous bursts of non-sequential pressure peaks occurred in the smooth muscle part of the human oesophagus in relation to phase 3 of the migrating motor complex. They represent the oesophageal body component of phase 3 of the migrating motor complex and are not a sign of oesophageal motor abnormalities.

Adult↗

Regulation of migrating motor complexes by motilin and pancreatic polypeptide in human infants.

In adults, migrating motor complexes (MMCs) appear to be partially under hormonal modulation by motilin and pancreatic polypeptide. Preterm infants do not exhibit MMCs until 32 wk of gestation. Although plasma concentrations of motilin are similar in infants and adults, it is not known if actual hormonal modulation of MMCs is present in infants. In the first study we assessed whether plasma concentrations of motilin and pancreatic polypeptide surge with the occurrence of MMCs in term infants. In the second study we assessed whether erythromycin, a motilin receptor agonist, could induce migrating motor activity in preterm and term infants. In the first study we recorded motor activity in nine term infants who had never been fed. We determined plasma concentrations of motilin and pancreatic polypeptide in the presence and absence of MMCs. In the second study we gave the motilin agonist erythromycin intragastrically to 21 infants at a range of 24-42 wk of gestation to assess whether migrating activity could be induced via the motilin receptor. In the first study, plasma concentrations of motilin were similar during the presence and absence of MMCs, as were plasma concentrations of pancreatic polypeptide. In the second study, the administration of erythromycin induced the appearance of migrating activity in 7 of 14 infants who were older than 32 wk but in none of the infants who was younger than 32 wk. Although the motilin receptor appears to be functionally present beyond 32 wk of gestation, as assessed by in indirect pharmacologic challenge, hormonal modulation of migrating activity in the neonate by plasma motilin and pancreatic polypeptide is absent.

Anti-Bacterial Agents↗

Effects of physical exercise on colonic motor activity.

We investigated the effect of physical exercise on colonic motor activity in the fasted and fed states in six conscious dogs. Each dog was implanted with nine strain gauge transducers: three on the proximal, three on the middle, and three on the distal colon. The dogs ran for 1 h on a treadmill at 5 km/h (slope 5%). In the fasted state, the dogs exercised during the 5th h of recording after an overnight fast, and in the fed state during the 1st, 3rd, and 5th postprandial hour. In the fasted state, exercise significantly decreased the frequency of colonic migrating motor complexes (MMCs) but had no effect on the total or the mean duration of contractile states in the proximal, middle, and distal colon. Postprandially, exercise disrupted colonic MMCs and replaced them with nonmigrating motor complexes in all three periods of exercise (1st, 3rd, and 6th h). Exercise also increased the total duration per hour of contractile activity throughout the colon during the 1st and 3rd h and only in the distal colon during the 6th h after the meal. The dogs never defecated during rest in the fasted or the fed state. Shortly after the start of exercise in the fasted and fed states, giant migrating contractions (GMCs) occurred, and they were followed by defecation. In approximately 40% of the experiments, another GMC originated in the proximal colon, approximately 10 min after the first defecation, and migrated caudad up to the middle colon. These GMCs were not associated with defecation but caused mass movements.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

[Effect of electroacupuncture on myoelectric activity of Jejunal limb After Roux-en-Y esophagojejunostomy].

OBJECTIVE: To explore the effect of electroacupuncture on myoelectric activity of Jejunal limb after Roux-en-Y esophagojejunostomy. METHODS: Fourteen health young pigs were randomly divided into 2 groups, an experimental group (total gastrectomy and Roux-en-Y esophagojejunostomy was carried out) and a control group (the abdominal cavity was closed after the electrode was placed), 7 pigs in each group. Electroacupunture was given at "Zusanli" (ST 36) in the experimental group. The changes of myoelectrogram of the jejunal limb was investigated. RESULTS: Compared with the control group, the amplitude and the frequency of the slow wave, and the amplitude and incidence rate of the spike potential in the experimental group were changed significantly; the duration of migrating motor complex (MMC) phase III was (2.6 +/- 0.7) minutes in the experimental group, which was significantly shorter than (7.1 +/- 1.1) minutes in the control group. Electroacupuncture did not significantly influence the amplitude and the frequency of the slow wave, but could increased significantly the incidence rate and the amplitude of the spike potential; after electroacupuncture, the duration of MMC phase III was (5.7 +/- 0.9) minutes, which was significantly longer than (2.6 +/- 0.7) minutes before electroacupuncture. CONCLUSION: Electroacupuncture at "Zusanli" (ST 36) can relieve the Roux-en-Y stasis syndrome through influencing myoelectric activity of the jejunum.

Anastomosis, Roux-en-Y↗

Effect of fluid perfusion and cleansing on canine colonic motor activity.

We investigated the effect of absorbable and nonabsorbable fluid perfusion and cleansing on colonic motor activity in eight intact conscious dogs. Each dog was instrumented with an indwelling catheter in the proximal colon and seven strain gauge transducers on the entire colon. After an overnight fast, a control recording was made for 3 h, followed by 3 h of perfusion and 3 additional h of postperfusion recording. Next day, a 3-h recording was made when the colon was empty. The colon exhibited normal migrating and nonmigrating motor complexes in the control uncleansed state. The perfusion of absorbable electrolyte or nonabsorbable Colyte solution immediately disrupted the migrating motor complexes and replaced them with almost continuous but irregular contractions at all recording sites. Both solutions significantly prolonged the mean and total duration per hour of contractile states in the proximal, middle, and distal colon. The dogs began to leak fluid stools in squirts approximately 40-80 min after the start of perfusion. This type of incontinence was not associated with any specific type of motor activity. Infrequently, giant migrating contractions occurred during perfusion and caused explosive diarrhea. The migrating motor complexes remained disrupted during the 3-h postperfusion period. However, on the next day, the empty colon exhibited normal migrating motor complexes. The frequency of giant migrating contractions during perfusion and in the empty colon was significantly greater than that in the normal uncleansed colon. The total duration per hour of colonic motor activity in the empty colon was also greater than that in the normal uncleansed colon. We conclude that excessive fluid in the colon significantly alters its motor pattern.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Micturition is associated with phase III of the interdigestive migrating motor complex in man.

OBJECTIVES: In previous manometric studies, we observed that micturition was associated with phase III of the migrating motor complex. The present study aimed to objectify this possible relationship and to examine whether modulation of micturition frequency influences migrating motor complex phase III incidence. METHODS: In a retrospective study, ambulatory antroduodenal manometry and micturition data of 27 subjects were analyzed. In a prospective study, antroduodenal motility and micturition patterns were studied in five subjects who were subjected to an oral water load. Volunteers were either allowed to micturate ad libitum or instructed to postpone micturition. RESULTS: In the retrospective part of the study, a statistically significant association was found between phase III and micturition. Of all micturitions, 50% took place during or within 10 min from phase III. Also, in the prospective part of the study, phase III and micturition, as well as micturition urge, showed a significant association (p < 0.05). CONCLUSION: Micturition and phase III of the migrating motor complex are associated in time.

Adult↗

Colonic motor response to a meal in acute colitis.

The symptoms of urgency, diarrhea, and abdominal discomfort are exaggerated after a meal in inflammatory disorders of the colon, such as ulcerative colitis. The possible motor correlates of these symptoms were investigated in a model of acute colitis in six dogs. Each dog was instrumented with seven strain gauge transducers, two on the proximal, three on the middle, and two on the distal colon. After an overnight fast, 4-hour fasted recordings were made from the normal colon and after the colon had been cleansed on the previous day with Colyte (Reed & Carnrick, Piscataway, NJ). A 1300-kcal meal was then fed, and the recordings were continued for another 8 hours. Acute colitis was then induced by the perfusion of 10 mL of 75% acetic acid and confirmed with colonoscopy and biopsy. The fasted and postprandial recordings were repeated during the next 5 days. In the control state, ingestion of the meal increased the total duration per hour of contractile activity in the early (0-2 hours) and late (2-8 hours) postprandial periods in the distal colon. In the proximal and the middle colon, a significant increase in motor activity occurred only during the late postprandial period. Similar effects were observed in the cleansed colon. By contrast, there was no significant increase in motor activity after a meal during colitis in any of the postprandial periods in the cleansed or the uncleansed colon. During colitis, there was a significant increase in the incidence of giant migrating contractions in the fasted state. The ingestion of a meal further increased the frequency of giant migrating contractions in the uncleansed colon from 0.4 +/- 0.1 to 1.3 +/- 0.5 per hour in the late postprandial period. There was no significant increase during the early postprandial period. The increase in the late postprandial frequency of giant migrating contractions was associated with an increase in defecation frequency. It is concluded that the motor response of the colon to a meal is absent in acute colitis. The entry of new ingesta into the colon during the late postprandial period stimulates enteric mechanisms to initiate an excessive number of giant migrating contractions. These giant migrating contractions may be related to increased postprandial abdominal discomfort and increased frequency of defecation.

Acute Disease↗

Canine ileal motor activity after a model of jejunoileal autotransplantation.

OBJECTIVE: To determine mechanisms by which extrinsic innervation to the jejunoileum controls ileal motility. SUMMARY BACKGROUND DATA: Small bowel transplantation is complicated by diarrhea and delayed gastric emptying, possibly secondary to altered motility. Ileal motility after small bowel transplantation is poorly characterized. METHODS: Motor activity was recorded from four dogs during fasting and after feeding small (64 Kcal) or large (256 Kcal) meals. Short-chain fatty acids known to induce unique ileal motor patterns were administered into the distal ileum during fasting. Dogs were studied before and after jejunoileal denervation simulating autotransplantation. RESULTS: After jejunoileal denervation, the ileal migrating motor complex (MMC) persisted but was no longer temporally coordinated with duodenal MMCs. Spontaneous giant migrating contractions occurred more frequently after denervation and more commonly originated proximally in the jejunum, but the velocity of migration did not differ. In contrast, the incidence and characteristics of spontaneous discrete clustered contractions (DCCs) did not differ. Short-chain fatty acids reproducibly initiated giant migrating contractions and discrete clustered contractions in the distal ileum without differences before and after denervation. Large but not small meals inhibited the ileal MMC after denervation. CONCLUSIONS: Extrinsic innervation and/or intrinsic neural continuity with the duodenum and/or colon control temporal coordination of ileal motility with the duodenum and modulate postprandial inhibition of fasting motility and presence of giant migrating contractions. These changes in motility patterns may prove important in mediating enteric dysfunction after small bowel transplantation.

Animals↗

Further classification of dysmotility-like dyspepsia by interdigestive gastroduodenal manometry and plasma motilin level.

OBJECTIVE: To investigate interdigestive gastroduodenal motility with an infused catheter and measure plasma motilin levels in eight normal individuals and 18 patients with dysmotility-like dyspepsia. METHODS AND RESULTS: All normal individuals had normal gastroduodenal interdigestive migrating complexes. Patients with dysmotility-like dyspepsia were classified into three subgroups on the basis of gastric antral motility: 1) seven patients with normal interdigestive migrating complexes, 2) five patients without interdigestive migrating complexes and with gastric phase II predominant over phase I, and 3) six patients without interdigestive migrating complexes and with phase I predominance. The maximum and mean plasma motilin levels were significantly different in normal individuals from those in subgroup 3 (Kruskal-Wallis test, p < 0.05). CONCLUSIONS: Dysmotility-like dyspepsia appears to be a heterogeneous condition. Abnormal motilin secretion may cause dysmotility in subgroup 3, but dyspepsia in subgroup 1 and the absence of interdigestive migrating complexes in subgroup 2 could not be explained only on this basis.

Adult↗

Trichinella spiralis infection alters small bowel motor activity in the fed state.

The effect of Trichinella spiralis infection on small intestinal transit and motor activity in the fed state during the intestinal phase of infection was studied. Contractions were recorded by strain gauge transducers, and mean transit time was measured by marker dilution technique. The mean amplitude and area of individual phasic contractions decreased, but no change occurred in their mean duration during trichinosis. The total amplitude and area of phasic contractions also decreased; this was caused by a decrease in the frequency of contractions as well as a decrease in the mean parameters. The reduction in the total duration was entirely caused by the decrease in frequency. The reduction in the total parameters of all contractions was the result of a reduction in the same parameters for both propagating and nonpropagating contractions. However, the decrease in the parameters of propagating contractions was much greater. Also, there was a decrease in the distance of propagation of phasic contractions. The transit time as a result of phasic contractions increased during T. spiralis infection. Additionally, T. spiralis infection induced giant migrating contractions in the fed state that were never observed during control. Chyme was propelled very rapidly and effectively by giant migrating contractions. The findings of the present study suggest that during diarrhea induced by T. spiralis infection, the phasic contractions may act to decrease transit and, hence, allow more contact time for absorption of water and nutrients. However, this response may be counter-balanced by giant migrating contractions that rapidly propel chyme into the colon and compound the diarrhea associated with T. spiralis infection.

Animals↗

Colonic migrating motor complexes (CMMCs) in the isolated mouse colon.

Spontaneous contractions were recorded from the circular muscle layer at three sites along the isolated mouse colon. The interval between contractions was approximately 4.5 min. The mean duration of the contractions ranged from 26 sec in the distal colon to 45 sec in the proximal colon. Contractions migrating more than half the length of the colon were termed colonic migrating motor complexes (CMMCs). Over 90% of tissues demonstrated migration predominantly in an aboral direction. Hyoscine (10(-6) M) decreased the amplitude of the CMMCs by at least 40% but had no significant effect on the interval or duration of the CMMCs. Nifedipine (10(-6) M) significantly decreased the amplitude of the CMMCs by 95% but did not alter the duration or the interval between the CMMCs. Hexamethonium (5 x 10(-4) M) and tetrodotoxin (TTX; 2 x 10(-6) M) abolished all CMMC activity. TTX increased the resting tone of the preparations. Nitro-L-arginine (10(-4) M) increased the resting tone of the preparations and significantly decreased the interval between the CMMCs by approximately 80% but had no significant effect on the duration of the CMMCs. The results suggest CMMCs migrate predominantly in an aboral direction and are neurogenic in origin. Nitric oxide may be involved in maintaining inhibition of the muscle between CMMCs.

Animals↗

Neural integrity is essential for the propagation of colonic migrating motor complexes in the mouse.

The mechanisms that underlie the propagation of contractions along the colon are uncertain. We have examined whether spontaneous colonic migrating motor complexes (CMMCs) migrate through a region of muscle paralysis, or through a region where neural transmission was disrupted in the isolated mouse colon. Mouse colon was mounted in a separately perfused three-compartment organ bath and recordings of circular muscle tension were made. Drug application was restricted to the middle compartment. Application of nifedipine (1 micromol L(-1)), an l-type calcium channel antagonist, reduced the contraction amplitude by approximately 94%, without affecting the form of contractions in the proximal and distal compartments. Moreover, CMMCs appeared to remain temporally related in all compartments. In contrast, interruption of neural transmission in the middle compartment by either tetrodotoxin (1.6 micromol L(-1)), hexamethonium (500 micromol L(-1)) or a low-calcium, high-magnesium solution abolished CMMCs in this compartment; contractions recorded in the proximal and distal compartments became slower in frequency and were no longer synchronized. The experiments suggest that there may be more than one 'pacemaker' generating spontaneous CMMCs and that CMMCs can migrate through a region where there is minimal tension generation, but not through a region where neural integrity has been compromised.

Animals↗

Concentration-dependent stimulation of intestinal phase III of migrating motor complex by circulating serotonin in humans.

1. The influence of circulating 5-hydroxytryptamine (serotonin) on small intestinal motility was investigated in healthy volunteers. 2. Small intestinal motility was studied by means of a constantly perfused multi-channel manometry tube, connected to a computer system. 3. Intravenous infusions of either 5-hydroxytryptamine at increasing doses or saline were given over a period of 4 h. 4. 5-Hydroxytryptamine infusion dose-dependently increased plasma 5-hydroxytryptamine from approximately 2 to 10 and 25 nmol/l respectively, as well as urinary excretions of 5-hydroxytryptamine and 5-hydroxyindole acetic acid, a major 5-hydroxytryptamine metabolite. 5. The number of phase III of the migrating motor complex originating in the small intestine was dose-dependently increased by 5-hydroxytryptamine, and found to correlate to the plasma concentration of 5-hydroxytryptamine. The fraction of phase III also increased at the expense of phase II activity. In addition, 5-hydroxytryptamine increased the motility index, propagation velocity of phase III activity and the amplitude of contractions during phase III. 6. Whereas the low dose of 5-hydroxytryptamine (15 nmol.min-1.kg-1) had no haemodynamic effects, an increase in heart rate by approximately 20 beats/min, without change in blood pressure, was observed at the higher dose (60 nmol.min-1.kg-1). Respiratory parameters did not change during infusion of 5-hydroxytrytamine at either dose. 7. In conclusion, elevation of circulating 5-hydroxytryptamine by intravenous infusion results in more frequent and faster propagating migrating motor complexes in the human small intestine during the inter-digestive period.

Adult↗

Spontaneous migrating motor complexes occur in both the terminal ileum and colon of the C57BL/6 mouse in vitro.

We have studied migrating motor complexes (MMCs) in the isolated terminal ileum or colon (IMMCs and CMMCs respectively) of the C57BL/6 mouse. Periodic contractions occurred spontaneously in both preparations in the absence of intraluminal stimulation. After an initial period, complexes became synchronized between the oral and anal ends of the tissue, and could be observed for in excess of 7 h. The propagation velocity was 3.1+/-1.0 and 3.9+/-0.6 mm s(-1) in the ileum and colon respectively. IMMCs occurred every 6.01+/-0.39 min and had a duration of 86.3+/-10.4 s. The interval between CMMCs was smaller (3.52+/-0.31 min) and contractions were shorter in duration (30.7+/-3.6 s). In both preparations, these motor events were dependent on cholinergic transmission: blocked by hexamethonium (500 microM) and attenuated or blocked by atropine (1 microM). This study is the first demonstration of spontaneous migrating contractions in the isolated ileum or colon of the C57BL/6 mouse, the strain of choice for neurological transgenic and targeted mice.

Animals↗