Colonic high-amplitude propagated contractions (mass movements): repeated 24-h manometric studies in healthy volunteers

Circadian rhythms in colonic function

A rhythmic expression of clock genes occurs within the cells of multiple organs and tissues throughout the body, termed "peripheral clocks." Peripheral clocks are subject to entrainment by a multitude of factors, many of which are directly or indirectly controlled by the light-entrainable clock located in the suprachiasmatic nucleus of the hypothalamus. Peripheral clocks occur in the gastrointestinal tract, notably the epithelia whose functions include regulation of absorption, permeability, and secretion of hormones; and in the myenteric plexus, which is the intrinsic neural network principally responsible for the coordination of muscular activity in the gut. This review focuses on the physiological circadian variation of major colonic functions and their entraining mechanisms, including colonic motility, absorption, hormone secretion, permeability, and pain signalling. Pathophysiological states such as irritable bowel syndrome and ulcerative colitis and their interactions with circadian rhythmicity are also described. Finally, the classic circadian hormone melatonin is discussed, which is expressed in the gut in greater quantities than the pineal gland, and whose exogenous use has been of therapeutic interest in treating colonic pathophysiological states, including those exacerbated by chronic circadian disruption.

The role of colonic motility in low anterior resection syndrome

Low anterior resection syndrome (LARS) describes the symptoms and experiences of bowel dysfunction experienced by patients after rectal cancer surgery. LARS is a complex and multifactorial syndrome exacerbated by factors such as low anastomotic height, defunctioning of the colon and neorectum, and radiotherapy. There has recently been growing awareness and understanding regarding the role of colonic motility as a contributing mechanism for LARS. It is well established that rectosigmoid motility serves an important role in coordinating rectal filling and maintaining continence. Resection of the rectosigmoid may therefore contribute to LARS through altered distal colonic and neorectal motility. This review evaluates the role of colonic motility within the broader pathophysiology of LARS and outlines future directions of research needed to enable targeted therapy for specific LARS phenotypes.

Colonic Function Investigations in Children: Review by the ESPGHAN Motility Working Group

Disorders of colonic motility, most often presenting as constipation, comprise one of the commonest causes of outpatient visits in pediatric gastroenterology. This review, discussed and created by the European Society for Pediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) Motility Working Group, is a practical guide, which highlights the recent advances in pediatric colonic motility testing including indications, technical principles of the tests, patient preparation, performance and basis of the results' analysis of the tests. classical methods, such as colonic transit time (cTT) with radiopaque markers and colonic scintigraphy, as well as manometry and novel techniques, such as wireless motility capsule and electromagnetic capsule tracking systems are discussed.

1907-2020: more than one century of colonic mass movements in humans

Motility of the large bowel may be grossly subdivided in two types of contractile activity: low-amplitude single or cyclic propagated waves and high-amplitude propagated activity. The latter is mainly apt to shift relatively large amounts of colonic contents, and it is related to defecation. The main component of this propagated activity is represented by the radiologically identified mass movements that have a manometric equivalent known as high-amplitude propagated contractions (HAPC). The present article reviews origins and characterization of HAPC in the time course of colonic motility investigations, and correlates it with technological advancements in recent years, putting into perspective the future possible options to better detect and investigate these important physiological events.

Characterization of the colonic response to bisacodyl in children with treatment-refractory constipation

BACKGROUND

Colonic manometry with intraluminal bisacodyl infusion can be used to assess colonic neuromuscular function in children with treatment-refractory constipation. If bisacodyl does not induce high-amplitude propagating contractions (HAPCs), this can be an indication for surgical intervention. A detailed characterization of the colonic response to intraluminal bisacodyl in children with constipation may help to inform clinical interpretation of colonic manometry studies.

METHODS

Studies were performed in five pediatric hospitals. Analysis included identification of HAPCs, reporting HAPCs characteristics, and an area under the curve (AUC) analysis. Comparisons were performed between hospitals, catheter type, placement techniques, and site of bisacodyl infusion.

RESULTS

One hundred and sixty-five children were included (median age 10, range 1-17 years; n = 96 girls). One thousand eight hundred and ninety-three HAPCs were identified in 154 children (12.3 ± 8.8 HAPCs per child, 0.32 ± 0.21 HAPCs per min; amplitude 113.6 ± 31.5 mm Hg; velocity 8.6 ± 3.8 mm/s, propagation length 368 ± 175 mm). The mean time to first HAPC following bisacodyl was 553 ± 669 s. Prior to the first HAPC, there was no change in AUC when comparing pre- vs post-bisacodyl (Z = -0.53, P = .60). The majority of HAPCs terminated in a synchronous pressurization in the rectosigmoid. Defecation was associated with HAPCs (χ² (1)=7.04, P < .01). Site of bisacodyl administration, catheter type, and hospital location did not alter the response.

CONCLUSIONS AND INFERENCES

Intraluminal bisacodyl induced HAPCs in 93% of children with treatment-refractory constipation. The bisacodyl response is characterized by ≥1 HAPC within 12 minutes of infusion. The majority of HAPCs terminate in a synchronous pressurization in the rectosigmoid. Optimal clinical management based upon colonic manometry findings is yet to be determined.

First translational consensus on terminology and definitions of colonic motility in animals and humans studied by manometric and other techniques

Alterations in colonic motility are implicated in the pathophysiology of bowel disorders, but high-resolution manometry of human colonic motor function has revealed that our knowledge of normal motor patterns is limited. Furthermore, various terminologies and definitions have been used to describe colonic motor patterns in children, adults and animals. An example is the distinction between the high-amplitude propagating contractions in humans and giant contractions in animals. Harmonized terminology and definitions are required that are applicable to the study of colonic motility performed by basic scientists and clinicians, as well as adult and paediatric gastroenterologists. As clinical studies increasingly require adequate animal models to develop and test new therapies, there is a need for rational use of terminology to describe those motor patterns that are equivalent between animals and humans. This Consensus Statement provides the first harmonized interpretation of commonly used terminology to describe colonic motor function and delineates possible similarities between motor patterns observed in animal models and humans in vitro (ex vivo) and in vivo. The consolidated terminology can be an impetus for new research that will considerably improve our understanding of colonic motor function and will facilitate the development and testing of new therapies for colonic motility disorders.

Gut Movements: A Review of the Physiology of Gastrointestinal Transit

The well-regulated mechanisms of intestinal transit favor aboral movement of intestinal contents during the formation of normal stool. Electrical pacemakers initiate mechanical smooth muscular propulsion under regulation by the enteric nervous system-a function of the "brain-gut axis." Several unique intestinal motor patterns function in concert to enhance the activities of intestinal transit. Development of pharmacologic targets of intestinal transit mechanisms afford clinicians control in the management of functional gastrointestinal disorders. This review highlights the important physiologic events of intestinal transit, discusses selected pharmacologic and neuromodulators involved in these processes, and provides relevant clinical correlates to physiologic events.

Normal aspects of colorectal motility and abnormalities in slow transit constipation

Human colonic motility is a relatively difficult topic to investigate. However, the refinement of manometric techniques in recent years enabled us to study both the proximal and distal segments of the viscus. The present paper reviews our knowledge about normal aspects of colorectal motility in man and the abnormalities found in slow transit constipation (STC), one of the most frequent and difficult to treat subtypes of constipation. An internet-based search strategy of the Medline and Science Citation Index was performed using the keywords colon, colonic, colorectal, constipation, slow transit, motility, rectal, rectum in various combinations with the Boolean operators AND, OR and NOT. Only articles related to human studies were used, and manual cross-referencing was also performed. Most of colonic motor activity is represented by single nonpropagated contractions, rarely organized in bursts; this activity is maximal during the day, especially after waking and following meals. In addition, a specialized propagated activity with propulsive features is detectable, represented by high- and low-amplitude propagated contractions. In the severe form of constipation represented by the slow transit type, the above motor activity is completely deranged. In fact, both basal segmental activity (especially in response to meals) and propagated activity (especially that of high amplitude) are usually decreased, and this may represent a physiologic marker of this disorder. Human colonic motor activity is quite a complex issue, still only partly understood and investigated, due to anatomic and physiological difficulties. In recent years, however, some more data have been obtained, even in proximal segments. These data have helped in elucidating, although only in part, some pathophysiological mechanisms of chronic constipation, and especially of the STC subtype.

Manometric techniques for the evaluation of colonic motor activity: current status

Colonic motility disorders are common conditions. However, our understanding of normal, and, consequently, pathological motor function of the colon remains limited, mainly due to the relative inaccessibility of this organ for study. Investigation of colonic motility may encompass one or more of the four separate components (myoelectric activity, phasic and tonic contractile activity and movement of intraluminal content) using electrophysiological, manometric or transit studies. Although transit studies provide the best 'functional' appreciation of colonic motor activity, and are the only techniques used in contemporary clinical practice, manometric methods are becoming increasingly popular, as they allow a direct study of colonic contractile activity over prolonged periods. To date, the majority of studies have been limited to the pelvic colon by a retrograde (per rectal) approach; however, recent technological advances have facilitated 'pan-colonic' investigation. This review concentrates on manometry of the human colon proximal to the sigmoid, and includes evaluation of both phasic and tonic motor activity, by utilization of perfused-tube and solid-state manometric catheters, and also the electronic barostat. Methodological techniques, experimental protocols and the analysis and interpretation of recorded data are critically explored, and a contemporary classification of colonic contractile activities is presented.

The effects of the specific 5HT(4) receptor agonist, prucalopride, on colonic motility in healthy volunteers

BACKGROUND

Prucalopride is a selective and specific 5-hydroxytryptamine(4) receptor agonist that is known to increase stool frequency and to accelerate colonic transit.

AIM

To investigate the effect of prucalopride on high-amplitude propagated contractions and segmental pressure waves in healthy volunteers.

METHODS

After 1 week of dosing (prucalopride or placebo in a double-blind, randomized, crossover fashion), colonic pressures were recorded in 10 healthy subjects using a solid-state pressure catheter with six sensors spaced 10 cm apart. Subjects kept diary records of their bowel habits (frequency, consistency and straining). High-amplitude propagated contractions were analysed visually, comparing their total numbers and using 10-min time windows. Segmental pressure waves were analysed using computer algorithms, quantifying the incidence, amplitude, duration and area under the curve of all detected peaks.

RESULTS

When taking prucalopride, stool frequency increased, consistency decreased and subjects strained less. Prucalopride just failed to increase the total number of high-amplitude propagated contractions (P=0.055). The number of 10-min time windows containing high-amplitude propagated contractions was increased by prucalopride (P=0.019). Prucalopride increased the area under the curve per 24 h (P=0.026).

CONCLUSIONS

The 5-hydroxytryptamine(4) receptor agonist prucalopride stimulates high-amplitude propagated contractions and increases segmental contractions, which is likely to be the underlying mechanism of its effect on bowel habits in healthy volunteers.

Twenty-four hour recordings of colonic motility in patients with diverticular disease: evidence for abnormal motility and propulsive activity

INTRODUCTION

Diverticular disease of the colon is one of the most common pathologic entities in western countries. Although altered motility of the large bowel is commonly believed to be one of the major pathophysiologic mechanisms, no convincing evidence has been reported yet. In fact, only a few conflicting studies concerning distal colonic motility (with no information on forceful propulsive activity) are available in the literature.

PURPOSE

The purpose of the present study was to investigate basal and stimulated (postprandial) colonic motility from the transverse (not affected), descending, and sigmoid colon in patients with diverticular disease, together with detection of high-amplitude propagated contractions (mass movements). Motility data from patients were compared with those obtained in healthy control subjects.

METHODS

Ten patients and 16 control subjects of both sexes were recruited for the study. In all subjects, colonic motility was recorded for a 24-hour period by a colonoscopically positioned manometric catheter. Two 1000-kcal mixed meals were served during the study.

RESULTS

Compared with control subjects, patients with diverticular disease displayed significantly increased amounts of motility in the affected segments; the response to a physiologic stimulus (meal) was also abnormal in the patients' group. Diverticular disease patients also had a significant increase of forceful propulsive activity compared with control subjects (average = 10.3 +/- 2.7/subject/day high-amplitude propagated contractions for patients and 5.5 +/- 0.8/subject/day for control subjects; P = 0.051); interestingly, about 20 percent of such activity was abnormal, being propagated in a retrograde fashion.

CONCLUSIONS

We concluded that patients with diverticular disease of the colon have abnormal motor and propulsive activities of the large bowel, which are confined to the affected segments.

Prolonged multi-point recording of colonic manometry in the unprepared human colon: providing insight into potentially relevant pressure wave parameters

OBJECTIVES

To determine the feasibility of and derive normative data for prolonged, 24-h, multipoint, closely spaced, water perfused manometry of the unprepared human colon.

METHODS

In 14 healthy volunteers, 24-h recordings were made using a water perfused, balloon-tipped, 17 lumen catheter which was passed pernasally and positioned so that 16 recording sites spanned the colon at 7.5 cm intervals from cecum to rectum. The area under the pressure curve and propagating pressure wave parameters were quantified for the 16 regions. High amplitude propagating sequences were defined as were rectal motor complexes.

RESULTS

Nasocolonic recording was well tolerated and achievable. Propagation sequences, including high amplitude propagating sequences, originated in the cecum (0.32 +/- 0.05/h) more frequently than in other regions and the extent of propagation correlated significantly with proximity of the site of sequence origin to the cecum (p < 0.001). Propagation velocity of propagating sequences was greater than high amplitude propagating sequences (p = 0.0002) and region-dependent, unlike high amplitude propagating sequences (p < 0.01). The frequency of propagating sequences did not increase after the meal, but frequency of high amplitude propagating sequences was increased significantly by the meal (p < 0.01). Rectal motor complexes were seen throughout the colon with no apparent periodicity.

CONCLUSIONS

Prolonged, multipoint, perfusion manometry of the unprepared colon provides improved spatial resolution of colonic motor patterns and confirms the diurnal and regional variations in propagating pressure waves detected in the prepared colon. The study demonstrates differences between high amplitude propagating sequences and propagating sequence parameters that may have functional significance; and also, that the rectal motor complex is a ubiquitous pan colonic motor pattern.

Low-amplitude propagated contractile waves: a relevant propulsive mechanism of human colon

BACKGROUND

Human colonic motility is still poorly understood, especially as far as concerns its propulsive function. Available data refer almost exclusively to the forceful propulsive activity, which is recognized as high-amplitude propagated contractions, the manometric equivalent of mass movements. By contrast, information on less vigorous propulsive contractions is still lacking.

AIMS

To investigate the presence and behaviour of low-amplitude propagated contractile waves (less than 50 mmHg in amplitude) in the colon of healthy humans during a 24-hour study period.

SUBJECTS AND METHODS

A series of 16 healthy volunteers of both sexes entered the study, and were investigated by a standard technique involving a colonoscopically-positioned manometric catheter. During the study, two standard 1,000 kcal mixed meal and a 450 kcal breakfast were served. The recordings were, therefore, scanned for the presence of low-amplitude propagated contractile waves (waves of less than 50 mmHg in amplitude, propagated over at least three consecutive recording ports), their daily distribution, and their relationship with physiological events.

RESULTS

Low-amplitude propagated contractile waves were constantly present in all the tracings, with an average of about 61 events/subject/day and a mean amplitude of about 20 mmHg. More than 80% of these events appeared during the day, with a significant (p<0.05) increase after meals and after morning awakening. In 25% of subjects, these waves were accompanied by emission of flatus.

CONCLUSIONS

In the human colon, low-amplitude propagated contractile waves are a constant physiological propulsive pattern, which is generally related to sleep-wake cycles and meal ingestion.

Spatial and temporal organization of pressure patterns throughout the unprepared colon during spontaneous defecation

OBJECTIVE

The aim of this study was to examine colonic motor events associated with spontaneous defecation in the entire unprepared human colon under physiological conditions.

METHODS

In 13 healthy volunteers a perfused, balloon-tipped, 17-lumen catheter (outer diameter, 3.5 mm; intersidehole spacing, 7.5 cm) was passed pernasally and positioned in the distal unprepared colon.

RESULTS

In the hour before spontaneous defecation, there was an increase in propagating sequence frequency (p = 0.04) and nonpropagating activity when compared to basal conditions (p < 0.0001). During this hour the spatial and temporal relationships among propagating sequences demonstrated a biphasic pattern. Both the early (proximal) and late (distal) colonic phases involved the whole colon and were characterized by respective antegrade and retrograde migration of site-of-origin of arrays of propagating sequences. There was a negative correlation between propagating sequence amplitude and the time interval from propagating sequence to stool expulsion (p = 0.008).

CONCLUSIONS

The colonic motor correlate of defecation is the colonic propagating sequence, the frequency and amplitude of which begin to increase as early as 1 h before stool expulsion. During the preexpulsive phase, the spatial and temporal relationship among the sites of origin of individual propagating sequences demonstrate a stereotypic anal followed by orad migration, which raises the possibility of control by long colocolonic pathways.

Limited exposure of the healthy distal colon to orally-dosed formulation is further exaggerated in active left-sided ulcerative colitis

BACKGROUND

Active distal ulcerative colitis is often resistant to topically acting oral formulations. We speculated that the left side of the colon is underexposed to orally-dosed topical agents in patients with active distal colitis.

METHODS

Twenty-two healthy volunteers (12 males, aged 22-47 years), and 10 patients (6 males, aged 33-73 years) with active left-sided ulcerative colitis ingested a Eudragit-coated gelatine capsule containing 111In-labelled amberlite resin on four successive days. Regional colonic distribution, transit times and percentage of daily dose resident were calculated from the average of four serial gamma camera images on the 4th day.

RESULTS

(mean [95% CI]). When compared to controls, patients with colitis had significantly faster total colon transit (24.3 h [9.5-39.1] vs. 51.7 h [41.1-62.3]) as well as faster proximal colon transit (18.7 h [9.1-28.3] vs. 36.7 [28.5-44.9]), and distal colon transit (3.1 h [-0.5 to 6.8] vs. 15.0 h [10.5-19.5]), respectively (all P < 0.01). Material was asymmetrically distributed in health (proximal colon 69% [63-76] vs. distal colon 31% [24-37]). This asymmetry was more extreme in colitis, with corresponding values of 91% [85-96] vs. 9% [4-15]. As a result colitics had less material in the left-sided colon (9% [4-15] vs. 31% [24-37]), P < 0. 001. Colitics had a significantly lower percentage of the daily dose resident within the left side of the colon compared to controls (13% [-2 to 28] vs. 63% [44-81]), P < 0.01.

CONCLUSIONS

Delayed release oral formulation is asymmetrically distributed within the colon in health. This asymmetry is exaggerated in active left-sided ulcerative colitis and, together with faster colonic transit, results in reduced exposure of the distal colon to orally-dosed topical agents.

Colonic motility in man: features in normal subjects and in patients with chronic idiopathic constipation

The human colon is still a relatively unknown viscus, especially concerning its motor activity. However, in recent years, techniques have been perfected that allow a better understanding of colonic motility, especially through prolonged recording periods. In this way, it has been demonstrated that the viscus contracts according to a circadian trend, is responsive to physiological stimuli (meals, sleep), and features high amplitude, propulsive contractions that are part of the complex dynamic of the defecatory process. These physiological properties and their alterations in patients with chronic idiopathic constipation are reviewed in this article.

Intact colonic motor response to sudden awakening from sleep in patients with chronic idiopathic (slow-transit) constipation

PURPOSE

There are few data about the relationships between colonic motor behavior and higher brain functions, such as sleep. Previous studies were done in healthy subjects, and it is unknown whether patients with functional motor disorders of the colon behave differently. This study was designed to characterize colonic motor activity in patients with constipation, both during sleep and after sudden awakening, and to compare it with that of healthy subjects. Our working hypothesis was that patients with constipation would have an impaired response to sudden awakening.

PATIENTS AND METHODS

Twelve chronically constipated women, 22 to 49 years old, were recruited for the study, and their data were compared with those obtained from 12 healthy female volunteers, 21 to 38 years old. Manometric studies were performed in the descending and sigmoid colon for 30 minutes during sleep (immediately before awakening) and 30 minutes after being awakened suddenly. A motility index was calculated before and after the stimulus.

RESULTS

In both groups motility in the descending and the sigmoid colon was almost absent during sleep and significantly increased after sudden awakening. No difference in postawakening values was found between patients with constipation and controls.

CONCLUSIONS

In patients with chronic constipation, the brain-gut control of some fundamental mechanisms governing colonic motility is preserved. These data suggest that the alterations of colonic motility described in chronic constipation may be caused by an intrinsic dysfunction of the viscus.

Does chronic supplementation of the diet with dietary fibre extracted from pea or carrot affect colonic motility in man?

The aim of the present study was to assess, in healthy volunteers and under physiological conditions, the acceptability, clinical tolerance and effects on colonic motility of chronic supplementation of the usual diet with new dietary fibre sources. Three studies were carried out, one after a period of habitual diet, and two after randomized 3-week periods of supplementation with fibre extracted either from pea hulls or carrots, added to the meals as a fine powder. The 24 h motility was recorded on an unprepared colon at five levels to determine the initiation site and the number of high amplitude propagated contractions (HAPC) and to quantify motor activity every 30 min, particularly in the two periods following lunch and breakfast. With the habitual diet the motility pattern was an irregular alternation of quiescence and sporadic non-propagated contractions. HAPC always started from the ascending colon and occurred mainly after breakfast. With either type of fibre the 24 h motor profiles, the 24 h variations and the number of HAPC were not significantly modified but a more distal initiation of HAPC was found. The colonic postprandial motor response was more diffuse after dietary enrichment with carrot fibre than after enrichment with pea-hull fibre. In healthy volunteers the long-term addition of fibre extracted from pea hulls and carrots to the usual diet was easy and well-tolerated without clinical side-effects, but with limited colonic motor effects. However, the more distal initiation of HAPC observed could be deleterious.

Human colonic motility: physiological aspects

From the point of view of its motor activity, the human colon is probably the least understood of the abdominal hollow viscera. This is due to several facts: a) its proximal portions are relatively inaccessible due to anatomical reasons; b) there is no reliable animal model due to the considerable anatomic-physiological differences among mammals. For instance, most deductions about human colonic motor activity have been drawn from experiences in cats and dogs, in which the colon displays a cecum which is almost atrophic, and the viscus is featureless and C-shaped, without the haustrations and the sharp angulations seen in man, c) the wide fluctuations of motility in the daily time course of the same individual makes the interpretation of many studies difficult, especially considering the fact that, until recently, most of the studies on human colonic motility have been conducted for relatively short (30-180 min) recording periods. Recently, however, techniques that allow recording from the proximal portions of the human colon have been developed, and prolonged (24 h or more) observations of myoelectrical and contractile events have been achieved, thus improving our knowledge of the normal physiologic properties of the viscus. These informations have furthermore been integrated and confirmed by scintigraphic techniques (less invasive), that allow the measurement of intracolonic flow activity. The purpose of the present paper is to review the physiological aspects of colonic motility in man, quoting animal studies where human ones are lacking. We will briefly introduce some basic concepts, then a more detailed description of the main topic will follow.

Relationship between sleep patterns and human colonic motor patterns

BACKGROUND/AIMS

The precise relationships among colonic motor patterns, depth of sleep, and awakening are incompletely understood. The aim of this study was to correlate human colonic motor patterns with sleep stage, nocturnal arousals, and waking.

METHODS

We monitored sleep and correlated sleep stage, arousals, and waking with pressures (area under curve and propagating contractions) recorded from the entire colon in 11 healthy volunteers.

RESULTS

Propagating contraction frequency (P = 0.01) and area under the curve (P = 0.001) were significantly reduced at night. There was a highly significant correlation between depth of sleep and suppression of area under curve (P = 0.001) and propagating contraction frequency (P = 0.0001). Propagating contractions were eliminated during slow-wave sleep. During rapid eye movement sleep, colonic pressure and propagating contraction frequency increased sharply to levels comparable with those found in stage 2 sleep. Transient arousal from stable sleep, with or without waking, was a potent and immediate stimulus for colonic propagating contractions.

CONCLUSIONS

Sleep per se has a profound inhibitory effect on propagating and nonpropagating activity and is the major determinant of diurnal variation of colonic motility. Propagating contractions are eliminated in slow-wave sleep. Rapid eye movement sleep, arousals, and waking have immediate stimulatory effects on colonic motility.