Jejunal Motor Activity Research Articles

Propagation patterns of jejunal motor activity measured by high-resolution water-perfused manometry.

The manometric diagnosis of severe intestinal dysmotility is performed at most institutions using catheters with 2-8 sensors 5-10cm apart. The recent application of high-resolution manometry catheters with closely spaced sensors to other gut segments has been highly successful. The objective of the present study was to determine the feasibility of a jejunal high-resolution manometry method and to carry out a descriptive analysis of normal jejunal motor function. A 36-channel high-resolution water-perfused manometry catheter (MMS-Laborie, Enschede, The Netherlands) was orally placed in the jejunum of 18 healthy subjects (10 men, eight women; 21-38 age range). Intestinal motility was recorded during 5h, 3 during fasting, and 2 after a 450kcal solid-liquid meal. Analysis of motility patterns was supported by computerized tools. All healthy subjects except one showed at least one complete migrating motor complex during the 3h fasting period. Phase III activity lasted 5±1min and migrated aborally at a velocity of 7±3cm/min. High-resolution spatial analysis showed that during phase III each individual contraction propagated rapidly (75±37cm/min) over a 32±10cm segment of the jejunum. During phase II, most contractile activity corresponded to propagated contractile events which increased in frequency from early to late phase II (0.5±0.9 vs 2.5±1.3 events/10min, respectively; p<0.001). After meal ingestion, non-propagated activity increased, whereas propagated events were less frequent than during late phase II. Jejunal motility analysis with high-resolution manometry identifies propagated contractile patterns which are not apparent with conventional manometric catheters.

Automated quantitative analysis of nocturnal jejunal motor activity identifies abnormalities in individuals and subgroups of patients with slow transit constipation

Objective Small bowel dysmotility has previously been demonstrated in some patients with slow transit constipation (STC), suggesting a generalized intestinal disorder. However, no study has addressed whether the incidence of small intestinal dysfunction differs between subgroups of patients in this heterogeneous population. Using appropriate methodology, we aimed to determine prospectively the proportion of individuals with abnormal small bowel motility, and to assess whether heterogeneity in terms of pattern of colonic transit delay (based on 111In diethylene-triamine-pentaacetic acid (DTPA) isotope scintigraphy), or mode of onset (based on clinical history) is of importance. Methods Thirty-seven patients with STC underwent 24-h ambulatory jejunal manometry; data were compared with those obtained in 38 healthy controls. Automated quantitative analysis of seven variables of the nocturnal migrating motor complex was performed, to assess whether differences existed between groups, and whether individual patients had evidence of small intestinal dysmotility, defined as two or more measures of migrating motor complex variables outside the normal range. Results Four variables differed significantly between STC patients and controls: in phase III, propagation was slower, duration was longer, and contraction amplitude was higher; in phase II, contraction frequency was increased. Seven of 24 patients with a generalized pattern of colonic transit delay had abnormal small bowel motility compared with none of 13 with a left-sided delay ( p < 0.04). These included four patients with chronic idiopathic symptoms and three with acquired symptoms. Conclusions Approximately one third of patients with a generalized delay in colonic transit had evidence of jejunal enteric neuromuscular dysfunction. Individual patients with a left-sided colonic delay did not satisfy the criteria for nocturnal small bowel dysmotility, but as a group, some differences were noted from controls. In contrast to previous reports, evidence of generalized enteric dysmotility may be present irrespective of the mode of onset.

Circadian pancreatic enzyme pattern and relationship between secretory and motor activity in fasting humans.

It is unknown whether nonparallel pancreatic enzyme output occurs under basal conditions in humans. We aimed to determine whether the circadian or wake-sleep cycle influences the relationship among pancreatic enzymes or between pancreatic secretory and jejunal motor activity. Using orojejunal multilumen intubation, we measured enzyme outputs and proximal jejunal motility index during consecutive daytime and nighttime periods in each of seven fasting, healthy volunteers. Enzyme outputs were correlated tightly during daytime phases of wakefulness and nighttime phases of sleep (r > 0.72, P < 0.001). During nocturnal phases of wakefulness, output of proteases (r = 0.84, P < 0.001), but not of amylase and trypsin (r = 0.12), remained associated. Nocturnally, particularly during sleep, pancreatic secretory activity was directly correlated with jejunal motility index (r > 0.50, P < 0.001). In conclusion, parallel secretion of pancreatic enzymes dominates throughout the circadian cycle. Nonparallel secretion during nocturnal phases of wakefulness may be due to merely circadian effects or to the coupling of the wake-sleep and the circadian cycle. The association between fluctuations of secretory and motor activity appears to be particularly tight during the night.

Small bowel motility and transit after aortic surgery

Objective: The inability to tolerate feedings after aortic surgery prolongs hospitalization. The aim of this study was to define jejunal manometric and small bowel transit characteristics associated with the ileus that follows transperitoneal aortic surgery. Methods: Five male patients who underwent transperitoneal infrarenal aortobifemoral bypass had intraoperative placement of a jejunal multilumen catheter. The open abdomen allowed precise placement of pressure recording ports at 20, 22, 24, 26, 28, and 38 cm past the ligament of Treitz. Three-hour manometric studies were done after surgery and for 3 postoperative days. The migrating motor complex was identified visually on the manometric tracings, and pressure waves were identified with computer and a motility index calculated. Motility data were compared with healthy control data previously reported in the literature. Small bowel transit was determined with barium and serial abdominal radiographs. Results: All patients had ileus develop with return of bowel sounds at 2 to 7 days (median, 6 days) and flatus at 3 to 9 days (median, 7 days) after surgery. Jejunal motor activity was present within 6 hours of surgery, but the motility index was less in patients then in control subjects. The postoperative migrating motor complexes differed from control subjects in having more phase I, less phase II, and more frequent phase IIIs. Phase III retrograde migration was common in the patients but not in the control subjects. Small bowel transit was 2 days or greater in all patients. Conclusion: Motor activity is present in the jejunum shortly after aortic surgery. However, the activity is decreased in intensity and the fasting cycle differs from control subjects. Retrograde migration of phase III is the most likely abnormality, resulting in delayed small bowel transit. The data would predict a high rate of enteral feeding intolerance early after surgery. Future studies should focus on pharmacologic manipulation to rapidly return small bowel motility to a more normal state after aortic surgery. (J Vasc Surg 2002;36:19-24.)

Jejunal manometry predicts tube feeding intolerance in the postoperative period.

Postoperative nutrition is best provided enterally; however, patients often develop intolerance to enteral feedings. Our aim was to prospectively identify abdominal examination and jejunal pressure activity associated with postoperative intolerance of enteral feedings. Twenty-nine patients underwent abdominal operation and needle catheter jejunostomy placement. Elemental tube feedings were started on the day after surgery and advanced to the caloric goal rate over three days. Patients whose feedings were slowed at the attending surgeon's discretion were defined as intolerant. Jejunal manometry and a standardized abdominal exam were performed on postoperative days 1, 3, and 5. Fifteen patients (52%) were intolerant of tube feedings and had decreased jejunal motor activity but more active bowel sounds prior to feedings. After feedings, intolerant patients developed abdominal distension, but other abdominal findings were inconsistent. A marked decrease in phase II of the migrating motility complex (MMC) and the lack of a fed response were present in both groups. The overall jejunal motility present on day 1 following surgery identifies patients that will not tolerate enteral feedings. The abdominal examination, MMC parameters, and motor response to feeding did not predict feeding intolerance.

5-HT-induced jejunal motor activity: enteric locus of action and receptor subtypes.

The role of 5-hydroxytryptamine (5-HT), its enteric locus of action, and receptor subtypes involved in the regulation of jejunal contractions were investigated by close intra-arterial infusions in conscious dogs. Close intra-arterial infusions of 5-HT in short segments of the jejunum stimulated phasic contractions that were blocked completely by atropine, partially by tetrodotoxin, and not affected by hexamethonium. This response was also blocked significantly by 5-HT2A and 5-HT2C receptor antagonists but was not affected by 5-HT1A/5-HT1B, 5-HT3, and 5-HT4 receptor antagonists. Spontaneous phase III contractions were inhibited significantly by 5-HT2A and 5-HT2C receptor antagonists, not affected by 5-HT1A/5-HT1B and 5-HT3 receptor antagonists, and enhanced by 5-HT4 receptor antagonists. Repeated close intra-arterial infusions of 5-HT over several days stimulated giant migrating contractions. We conclude that in the conscious state, 5-HT acts on 5-HT2A and 5-HT2C receptors located on postsynaptic cholinergic neurons in the canine jejunum to stimulate phasic contractions and phase III activity. The 5-HT4 receptors in the canine small intestine may be localized on nonadrenergic, noncholinergic inhibitory neurons; these receptors suppress the amplitude and duration of phase III activity.

Jejunoileal transplantation

This study was designed to determine if extrinsic innervation and intrinsic neural continuity with the duodenum (neuroenteric physiologic pathways disrupted during intestinal transplantation) modulate the characteristics of interdigestive motor activity in the canine small bowel. Five dogs served as neurally intact controls (group 1) and 10 dogs (group 2) underwent a model of jejunal autotransplantation involving in situ neural isolation of the jejunoileum. Fasting duodenal and jejunal motor activity was recorded on-line to a microcomputer using closely spaced duodenal and jejunal manometry catheters. Characteristics of global motor patterns, the migrating motor complex (MMC), and local motor patterns, including individual contractions and grouped clustered contractions, were determined. Neural isolation of the jejunoileum disrupted coordination of duodenal and jejunal phase III activity, increased the variability of cycling of the MMC, decreased the period of the jejunal MMC, and increased motility indices in the neurally isolated jejunum. In contrast, single pressure waves and clustered contractions in the neurally isolated jejunum were not altered significantly in incidence or direction, distance, or velocity of spread. In situ neural isolation of the jejunoileum leads to temporal dissociation of the MMC between the transplanted segment (jejunum) and the duodenum but does not appear to alter markedly the characteristics of local contractile activity as measured by individual or grouped contractions. The occurrence of interdigestive jejunal motor patterns and the local organization of individual and grouped small intestinal contractions are not controlled by extrinsic innervation or intrinsic neural continuity with the duodenum.

Jejunal sensorimotor dysfunction in irritable bowel syndrome: Clinical and psychosocial features

BACKGROUND & AIMS: The interrelationships between enteric hypersensitivity, dysmotility, and psychosocial factors in the pathogenesis of irritable bowel syndrome (IBS) are poorly understood. The aims of this study were to (1) compare the clinical, jejunal motor, and psychological features in patients with IBS who have heightened sensitivity and those who have normal sensitivity to jejunal balloon distention and (2) examine psychosocial correlates of sensory and/or motor dysfunction. METHODS: Female patients with IBS (n = 24) and healthy controls (n = 9) underwent 24-hour ambulant duodenojejunal manometry, assessment of jejunal sensitivity by balloon distention, and comprehensive psychosocial assessment. RESULTS: In 6 (25%) and 10 (42%) patients, hypersensitivity was present at the threshold for initial perception and at the threshold for pain, respectively. After ingestion of a high-energy standard meal, all patients with heightened sensitivity for perception had abnormalities in the postprandial motor pattern compared with one third of patients with normal sensitivity. In this subgroup with hypersensitivity and postprandial dysmotility, clinical features were not discriminative but an inherently ineffectual coping style featuring both anger hyperreactivity and defensive control of anger was highly characteristic. CONCLUSIONS: In IBS, abnormal postprandial jejunal motor activity is related to jejunal mechanoreceptor-related hypersensitivity, and such sensorimotor dysfunction has a specific psychological profile. (Gastroenterology 1996 Feb;110(2):393-404)

Jejunoileal extrinsic denervation increases jejunal motor activity after abdominal operation: [formula omitted], J. Simmons, S. Burgess, R. Hansen. Department of Surgery, University of Missouri, Columbia, MO

Jejunoileal extrinsic denervation increases jejunal motor activity after abdominal operation: [formula omitted], J. Simmons, S. Burgess, R. Hansen. Department of Surgery, University of Missouri, Columbia, MO

Effects of the prodrug loperamide oxide, loperamide, and placebo on jejunal motor activity

This crossover, double-blind study investigated the effects of single oral doses of the prodrug loperamide oxide, which is reduced gradually to loperamide in the intestine, and loperamide on jejunal motor activity in 12 fasting healthy men. Five minutes after a phase III of the migrating motor complex (MMC), 2 mg loperamide oxide, 4 mg loperamide oxide, 4 mg loperamide, or placebo were administered. Thereafter, motor activity 10-30 cm abroad the ligament of Treitz was recorded with five catheter orifices at 3-cm intervals over 4 hr. Number of contractions and area under curve increased significantly with 4 mg loperamide and 4 mg loperamide oxide, the increases with loperamide oxide occurring more gradually. Placebo and 2 mg loperamide oxide had no discernible effects. With both 4 mg loperamide and 4 mg loperamide oxide, phase I of the MMC was slightly prolonged and phase II and the time from drug administration to the onset of the first phase III slightly shortened. The percentage of aborally propagated contractions in phase II increased with all active treatments, whereas the occurrence of phases III was not altered.

Effects of Acute Psychologic Stress on Small-Intestinal Motility in Health and the Irritable Bowel Syndrome

Psychologic stress may be a provoking factor in the alterations in phase-2 motor activity of the migrating motor complex (MMC) which have been recorded in patients with the irritable bowel syndrome (IBS). To test this, changes in phase-2 duodenojejunal motor activity during 20 min of psychologic stress in 10 patients with IBS were compared with those shown by 10 healthy subjects. Autonomic arousal in response to the stressor was assessed by cardiovascular responses and self-reported levels of anxiety and tension. IBS and controls showed a significant cardiovascular and subjective response to stress which was comparable in the two groups. In general, duodenal phase-2 motor activity was suppressed during stress in both IBS and controls. Jejunal motor activity showed a similar inhibitory response in both groups, but the change in motility index was significant for controls only. Qualitatively, stress did not cause clustered contractions in either the IBS or the control group. However, in IBS patients with clustered contractions in the basal period there was inhibition of this pattern during stress. These findings suggest that acute psychologic stress profoundly suppresses, rather than enhances, duodenojejunal MMC phase-2 motility in healthy subjects. IBS patients, irrespective of their underlying phase-2 motor pattern show similar, although less marked, changes in motility.

Neural modulation of jejunal motor activity during enteric infection with Trichinella spiralis in the Ferret

Neural modulation of jejunal motor activity during enteric infection with Trichinella spiralis in the Ferret

Medullary sites mediating some abdominal vagal reflexes in the ferret using [ 14C]2-deoxyglucose

The central projections of some abdominal visceral afferents passing through the vagal communicating branch were studied in anesthetized ferrets using [ 14C]2-deoxyglucose autoradiography. The reflex effects of electrical stimulation of the vagal communicating branch were studied while measurements of jejunal motor activity and transmural potential difference, a marker of electrogenic epithelial transport were made concurrently. The aim of this study was to examine brainstem projections of some afferent fibers in the communicating branch of the thoracic vagus nerve that are necessary for the reflex regulation of small intestinal motor activity and epithelial transport. In urethane-anesthetized ferrets, electrical stimulation of the cur central end of the vagal communicating branch increased jejunal motor activity and electrogenic epithelial transport. In addition, glucose utilization in the left medial sub-nucleus of the nucleus tractus solitarius and the dorsal motor nucleus of the vagus was significantly increased as compared with sham-operated non-stimulated control animals. Identical areas on the contralateral side of the brain showed no change in glucose utilization as compared with sham-operated non-stimulated controls. This functional brain-mapping study strongly suggests that the left medial sub-nucleus tractus solitarius and the dorsal motor nucleus of the vagus, in the ferret, are involved in processing alimentary affrent activity from both the small intestinal musculature and epithelium as well as the reflex changes in efferent vagal nerve activity to the same regions of the alimentary tract.

Effects of substance P and vasoactive intestinal polypeptide on contractile activity and epithelial transport in the ferret jejunum

Previous studies in the ferret demonstrated that vagal nerve stimulation induced an atropine-resistant water secretion. Substance P and vasoactive intestinal polypeptide are possible mediators of this secretory response. The objectives of this study were to investigate the in vivo effects of substance P and vasoactive intestinal polypeptide on the jejunal musculature and epithelium. Substance P caused an increase in jejunal motility, water secretion, and transmural potential difference. Cholinergic blockade did not affect the substance P-induced contractions, but did reduce the increase in transmural potential difference, suggesting an inhibition of water secretion. Vasoactive intestinal polypeptide abolished motor activity; however, it induced an increase in transmural potential difference that was atropine and tetrodotoxin resistant. By immunohistochemical methods, immunoreactive vasoactive intestinal polypeptide and immunoreactive substance P were localized to both nerve cell bodies and nerve fibers in the ferret intestine. Determination of intestinal concentrations of vasoactive intestinal polypeptide and substance P in the ferret showed concentrations of these two neuropeptides that were similar to those in human intestine and demonstrated much higher concentrations of these substances in the muscular layer than in the epithelial layer. Our data demonstrate that in the ferret substance P excites and vasoactive intestinal polypeptide inhibits jejunal motor activity. However, both peptides increase water secretion. Our results suggest that in response to vagal stimulation, neuronally released substance P or vasoactive intestinal polypeptide may participate in the atropine-resistant water secretion.

Effects of cisapride on postcibal jejunal motor activity

In the jejunum of fasting humans, cisapride induces a phase 2-like, highly propagative motor pattern. This study investigated cisapride's effects on the fed pattern of the jejunum. Starting 5 min after a phase 3 of the migrating motor complex, 18 healthy men received 5 or 10 mg cisapride or placebo orally in random double-blind fashion and ingested meals containing 1000 and 4200 kJ, respectively. Jejunal pressures were recorded pneumohydraulically with five catheter orifices 10-30 cm aboard the ligament of Treitz. After the 4200-kJ meal, total number and number of propagated contractions as well as area under the curve increased significantly more than after 1000 kJ. Following the 1000-kJ but not the 4200-kJ meal, 10 mg cisapride increased total number of contractions, number of propagated contractions, mean amplitude, and area under curve significantly more than placebo. Fed-pattern duration increased with the meal's caloric content but was not influenced systematically by cisapride. In conclusion, cisapride stimulates jejunal motor activity and induces a propagative pattern after a 1000-kJ but not after a 4200-kJ meal, suggesting that it can produce no further stimulation when motor activity is near maximally enhanced already.

Cisapride: increases jejunal phase 2-like motor activity but is accompanied by increased systolic BP and heart rate

Cisapride: increases jejunal phase 2-like motor activity but is accompanied by increased systolic BP and heart rate

The effect of insulin-induced hypoglycaemia on gastrointestinal motility in man

The effect of insulin-induced hypoglycaemia on gastro-jejunal motility was studied in five, healthy, male subjects using tethered, pressure sensitive, radiotelemetry capsules. Thirty minutes after the intravenous injection of soluble insulin (0.15 unit/kg body weight), a significant reduction in blood glucose concentration (control: 5.26 +/- 0.19 SEM mmol/l; insulin: 1.48 +/- 0.44 mmol/l; P less than 0.001) was associated with a rise in heart rate (mean peak rise 29 +/- 8 beats/min, P less than 0.05), systolic arterial blood pressure (mean peak rise 28 +/- 4 mmHg, P less than 0.01) and plasma pancreatic polypeptide concentration (control: 20 +/- 7 pmol/l; insulin: 287 +/- 66 pmol/l; P less than 0.01). These events coincided with a short period of jejunal motor activity, which was not associated with gastric motor activity nor with raised plasma motilin concentrations. During the control study, there were no changes in blood glucose concentration, heart rate, arterial blood pressure or plasma pancreatic polypeptide concentrations, and there was no jejunal motor activity. The interval between successive gastric migrating motor complexes (MMC) was not significantly different in the insulin and control studies (control: median interval 110 min, range 108-148 min; insulin: median interval 124 min, range 115-125 min), suggesting that the fasting gastrojejunal MMC and jejunal motor activity arose independently. Insulin-induced hypoglycaemia is accompanied by jejunal motor activity, which may underlie the abdominal symptoms associated with hypoglycaemia.

Effects of cisapride on jejunal motor activity in fasting healthy humans

The effects of cisapride on jejunal interdigestive motor activity were studied in 12 healthy men participating in three experiments each. Five minutes after an activity front (phase III) they received, in random double-blind fashion, 10 mg of cisapride, 4 mg of cisapride, or saline placebo by intravenous injection. Motor activity was recorded for 4 h. A pneumohydraulic perfusion system and five catheters with orifices positioned 10–30 cm beyond the ligament of Treitz were used. Cisapride increased phase II-type activity (p < 0.001) and reduced the number of activity fronts dose-dependently. Compared with phase II after placebo, the activity prevailing after cisapride was characterized by a significantly higher number and amplitude of contractions as well as by a significantly greater area under the pressure curve. Moreover, a significantly higher proportion of contractions was propagated aborally. Self-rated abdominal grumbling increased dose-dependently. Except for mild sedative effects, no side effects occurred. We conclude that cisapride induces a prolonged and highly propagative phase II-like jejunal motor activity in fasting humans.

Effects of laxative and nonlaxative hydrophilic polymers on canine small intestinal motor activity.

Bulk-forming laxatives increase fecal volume and elicit aborally directed colonic motility patterns. Recently, it was demonstrated that test meals of the bulk-laxative fibers (cellulose and bran) elicited organized jejunal motor activity while nonlaxative fiber meals (guar) elicited unorganized jejunal motor activity. However, whether bulk-forming laxatives, as a class of compounds, differentially affect small intestinal motility has not been studied. Therefore, a study was made of the effects of the bulk laxatives psyllium and polycarbophil and the nonlaxative pectin on canine jejunal motor activity. Psyllium and pectin are examples of dietary fiber, while polycarbophil is a synthetic polymer. Pectin and psyllium test meals presented as viscous gels. In contrast, polycarbophil meals presented as a combination of discrete particles plus meal water. After each meal, measurements were made of the jejunal motility index, the time of reappearance of interdigestive burst activity, and overall motility patterns. Pectin and psyllium meals increased in viscosity as meal fiber content increased. As meal content and hence viscosity increased, both the laxative (psyllium) and nonlaxative (pectin) fiber meals elicited increasing jejunal motor activity and delays in the reappearance of the burst interval. For both fiber types, motor activity presented as randomly appearing contractions. In contrast, meals of the laxative polycarbophil elicited no more motor activity than the saline control meal. However, this control-level amount of activity presented as propagated clusters of contractions, ie, the "laxative-induced pattern." Polycarbophil did not delay the reappearance of burst activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Role of extrinsic and intrinsic nerves in the relationship between intestinal motility and transmural potential difference in the anesthetized ferret

In the anesthetized ferret jejunum, the role of extrinsic and intrinsic nerves in the relationship between intestinal motor activity and transmural potential difference (PD) was studied. In the vagally intact ferret and after sympathetic blockade, spontaneous bursts of jejunal motor activity were associated with fluctuations in transmural PD. Both responses were abolished by vagotomy, atropine, and tetrodotoxin. Prolonged electrical stimulation of the cervical vagus nerve induced a cyclical motility pattern. Furthermore there was an initial rise in transmural PD which then plateaued, and superimposed on this were fluctuations in transmural PD. Atropine abolished the phasic pattern of motor activity and the fluctuations in transmural PD, although the tonic increase in transmural PD was not blocked. The results indicate that nervous activity, either spontaneous or induced, must be present for the cyclic fluctuations in transmural PD and motility. However, fluctuations in transmural PD associated with intestinal motility are not directly dependent on an intact vagal or sympathetic supply and involve coordination with the enteric nervous system.