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Gut Oct 2004
Review
Topics: Esophageal Motility Disorders; Esophageal Sphincter, Lower; Esophagus; Humans; Peristalsis
PubMed: 15361508
DOI: 10.1136/gut.2003.035618 -
World Journal of Gastroenterology Mar 2007The peristaltic transport of swallowed material in the esophagus is a neuro-muscular function involving the nerve control, bolus-structure interaction, and... (Review)
Review
The peristaltic transport of swallowed material in the esophagus is a neuro-muscular function involving the nerve control, bolus-structure interaction, and structure-mechanics relationship of the tissue. In this study, a finite element model (FEM) was developed to simulate food transport through the esophagus. The FEM consists of three components, i.e., tissue, food bolus and peristaltic wave, as well as the interactions between them. The transport process was simulated as three stages, i.e., the filling of fluid, contraction of circular muscle and traveling of peristaltic wave. It was found that the maximal passive intraluminal pressure due to bolus expansion was in the range of 0.8-10 kPa and it increased with bolus volume and fluid viscosity. It was found that the highest normal and shear stresses were at the inner surface of muscle layer. In addition, the peak pressure required for the fluid flow was predicted to be 1-15 kPa at the bolus tail. The diseases of systemic sclerosis or osteogenesis imperfecta, with the remodeled microstructures and mechanical properties, might induce the malfunction of esophageal transport. In conclusion, the current simulation was demonstrated to be able to capture the main characteristics in the intraluminal pressure and bolus geometry as measured experimentally. Therefore, the finite element model established in this study could be used to further explore the mechanism of esophageal transport in various clinical applications.
Topics: Computer Simulation; Deglutition; Esophagus; Finite Element Analysis; Humans; Mathematics; Models, Biological; Muscle Contraction; Muscle, Smooth; Peristalsis
PubMed: 17457965
DOI: 10.3748/wjg.v13.i9.1352 -
Journal of Clinical Gastroenterology 2008Two recent advances have revolutionized the performance of clinical esophageal manometry; the introduction of practical high resolution manometry (HRM) systems and the... (Review)
Review
Two recent advances have revolutionized the performance of clinical esophageal manometry; the introduction of practical high resolution manometry (HRM) systems and the development of sophisticated algorithms to display the expanded manometric dataset as pressure topography plots. We utilized a large clinical experience of 400 consecutive patients and 75 control subjects to develop a systematic approach to analyzing esophageal motility using HRM and pressure topography plots. The resultant classification scheme has been named as the Chicago Classification of esophageal motility. Two strengths of pressure topography plots compared with conventional manometric recordings were the ability to (1) delineate the spatial limits, vigor, and integrity of individual contractile segments along the esophagus and (2) to distinguish between loci of compartmentalized intraesophageal pressurization and rapidly propagated contractions. Making these distinctions objectified the identification of distal esophageal spasm, vigorous achalasia, functional obstruction, and nutcracker esophagus subtypes. Applying these distinctions made the diagnosis of spastic disorders quite rare: spasm in 1.5% of patients, vigorous achalasia in 1.5%, and a newly defined entity, spastic nutcracker, in 1.5%. Ultimately, further clinical experience will be the judge, but it is our expectation that pressure topography analysis of HRM data, along with its well-defined functional implications, will prove valuable in the clinical management of esophageal motility disorders.
Topics: Esophageal Motility Disorders; Esophagus; Humans; Image Processing, Computer-Assisted; Manometry; Peristalsis; Pressure; Reproducibility of Results
PubMed: 18364587
DOI: 10.1097/MCG.0b013e31815ea291 -
American Journal of Physiology.... Jun 2010The neuronal mechanism by which distension of the colon triggers peristalsis and the propulsion of colonic contents is incompletely understood. In this study, we used...
The neuronal mechanism by which distension of the colon triggers peristalsis and the propulsion of colonic contents is incompletely understood. In this study, we used video imaging and spatiotemporal mapping techniques to investigate the neuroneuronal mechanisms underlying peristalsis in isolated guinea pig distal colon. In direct contrast to previous studies, we found that hexamethonium (100 muM-1 mM) or mecamylamine (20 muM) never abolished peristalsis or fecal pellet propulsion, although a temporary blockade of peristalsis was common, giving the impression perhaps that peristalsis was blocked permanently. During the initiation of peristalsis, the intraluminal propulsive force applied to an inserted fecal pellet was significantly reduced by hexamethonium 100 muM, even though, once initiated, the propagation velocity of fecal pellets was never reduced by nicotinic antagonists. In the presence of hexamethonium or mecamylamine, further addition of PPADS (10 muM), ondansetron (1 muM), and SR 142801 (300 nM) had no inhibitory effect on the propagation velocity of fecal pellets. In these preparations, antagonists for nicotinic, purinergic (P2), serotonergic (5-HT3), or tachykinergic (NK3) receptors always abolished responses to the agonists for these receptors, confirming that when peristalsis occurred, nicotinic, P2, 5-HT3, and NK3 receptors were blocked. Tetrodotoxin abolished nonnicotinic peristalsis. In summary, nicotinic transmission contributes to excitatory neuroneuronal transmission underlying peristalsis and fecal pellet propulsion but is not required for peristalsis, nor fecal pellet propulsion, as once thought. These observations could be explained by an excitatory nonnicotinic neuroneuronal pathway that can generate peristalsis and induce normal fecal pellet propagation velocities but does not require nicotinic, P2, 5-HT3, or NK3 receptors.
Topics: Animals; Colon; Feces; Guinea Pigs; Male; Nicotinic Antagonists; Peristalsis; Purinergic Antagonists; Receptors, Nicotinic; Receptors, Purinergic; Receptors, Serotonin; Receptors, Tachykinin; Serotonin Antagonists
PubMed: 20360134
DOI: 10.1152/ajpgi.00457.2009 -
Anesthesiology Dec 2002Inhibition of intestinal peristalsis is a major side effect of drugs used for anesthesia or for analgesia and sedation of patients in the intensive care unit. This in...
BACKGROUND
Inhibition of intestinal peristalsis is a major side effect of drugs used for anesthesia or for analgesia and sedation of patients in the intensive care unit. This in vitro study examined the effect of clonidine and dexmedetomidine on intestinal peristalsis and analyzed some of their mechanisms of action.
METHODS
In isolated segments of the guinea pig small intestine, peristalsis was triggered by a perfusion-induced rise of the intraluminal pressure. The peristaltic pressure threshold to elicit a peristaltic wave was used to quantify drug effects on peristalsis. Vehicle (Tyrode's solution), clonidine (10 nM-100 microm), or dexmedetomidine (0.1-100 nM) were added extraserosally to the organ bath. In other series of experiments, clonidine or dexmedetomidine was administered after pretreatment with yohimbine, prazosin, apamin, naloxone, or vehicle. Clonidine was also tested after blockade of NO synthase with L-NAME and in the presence of the inactive enantiomer D-NAME.
RESULTS
Clonidine and dexmedetomidine concentration-dependently increased peristaltic pressure threshold and inhibited peristalsis (clonidine: EC50 = 19.6 microm; dexmedetomidine: EC50 = 12.0 nM). The inhibition caused by clonidine could be prevented by pretreatment with yohimbine, naloxone, and apamin, but not by prazosin, L-NAME, or D-NAME. Inhibition caused by dexmedetomidine was prevented by yohimbine only.(50) (50)
CONCLUSIONS
The results reveal that clonidine and, much more potently, dexmedetomidine inhibit peristalsis of the guinea pig ileum. The inhibition is caused by interaction with alpha2 adrenoceptors and, in the case of clonidine, also involves activation of small conductance Ca2+ -activated potassium channels and endogenous opioidergic pathways.
Topics: Adrenergic alpha-Agonists; Animals; Clonidine; Dexmedetomidine; Female; Guinea Pigs; Ileum; Male; Peristalsis
PubMed: 12459676
DOI: 10.1097/00000542-200212000-00022 -
American Journal of Physiology.... Jan 2009Peristaltic motor activity of the gut is an essential activity to sustain life. In each gut organ, a multitude of overlapping mechanisms has developed to acquire the... (Review)
Review
Peristaltic motor activity of the gut is an essential activity to sustain life. In each gut organ, a multitude of overlapping mechanisms has developed to acquire the ability of coordinated contractile activity under a variety of circumstances and in response to a variety of stimuli. The presence of several simultaneously operating control systems is a challenge for investigators who focus on the role of one particular control activity since it is often not possible to decipher which control systems are operating or dominant in a particular situation. A crucial advantage of multiple control systems is that gut motility control can withstand injury to one or more of its components. Our efforts to increase understanding of control mechanism are not helped by recent attempts to eliminate proven control systems such as interstitial cells of Cajal (ICC) as pacemaker cells, or intrinsic sensory neurons, nor does it help to view peristalsis as a simple reflex. This review focuses on the role of ICC as slow-wave pacemaker cells and places ICC into the context of other control mechanisms, including control systems intrinsic to smooth muscle cells. It also addresses some areas of controversy related to the origin and propagation of pacemaker activity. The urge to simplify may have its roots in the wish to see the gut as a consequence of a single perfect design experiment whereas in reality the control mechanisms of the gut are the messy result of adaptive changes over millions of years that have created complementary and overlapping control systems. All these systems together reliably perform the task of moving and mixing gut content to provide us with essential nutrients.
Topics: Action Potentials; Animals; Biological Clocks; Enteric Nervous System; Gastrointestinal Tract; Gastrointestinal Transit; Humans; Models, Biological; Motor Neurons; Peristalsis; Time Factors
PubMed: 18988693
DOI: 10.1152/ajpgi.90380.2008 -
International Journal of Biological... Jun 2023In this work, simulations of intestinal peristalsis are performed to investigate the intraluminal transport of macromolecules (MMs) and permeation enhancers (PEs)....
In this work, simulations of intestinal peristalsis are performed to investigate the intraluminal transport of macromolecules (MMs) and permeation enhancers (PEs). Properties of insulin and sodium caprate (C) are used to represent the general class of MM and PE molecules. Nuclear magnetic resonance spectroscopy was used to obtain the diffusivity of C, and coarse-grain molecular dynamics simulations were carried out to estimate the concentration-dependent diffusivity of C. A segment of the small intestine with the length of 29.75 cm was modeled. Peristaltic speed, pocket size, release location, and occlusion ratio of the peristaltic wave were varied to study the effect on drug transport. It was observed that the maximum concentration at the epithelial surface for the PE and the MM increased by 397 % and 380 %, respectively, when the peristaltic wave speed was decreased from 1.5 to 0.5 cm s. At this wave speed, physiologically relevant concentrations of PE were found at the epithelial surface. However, when the occlusion ratio is increased from 0.3 to 0.7, the concentration approaches zero. These results suggest that a slower-moving and more contracted peristaltic wave leads to higher efficiency in transporting mass to the epithelial wall during the peristalsis phases of the migrating motor complex.
Topics: Peristalsis; Intestine, Small; Biological Transport
PubMed: 37059282
DOI: 10.1016/j.ijbiomac.2023.124388 -
JAMA Surgery Feb 2013Although successful treatment of achalasia depends on alleviating the obstruction at the esophagogastric junction, the postintervention contractile and pressurization... (Comparative Study)
Comparative Study
IMPORTANCE
Although successful treatment of achalasia depends on alleviating the obstruction at the esophagogastric junction, the postintervention contractile and pressurization pattern may also play a role in outcome.
OBJECTIVE
To determine whether myotomy that alleviates the esophagogastric junction outflow obstruction in achalasia might improve peristalsis.
DESIGN
Retrospective study from August 1, 2004, through January 30, 2012.
SETTING
Two tertiary care hospitals in Chicago and Lyon.
PATIENTS
We included 30 patients (18 male; mean age [range], 43 [17-78] years), of whom 8 had type 1 (26.6%), 17 had type 2 (56.7%), and 5 (16.7%) had type 3 achalasia according to the Chicago classification.
INTERVENTIONS
Esophageal high-resolution manometry before and after laparoscopic or endoscopic myotomy.
MAIN OUTCOMES MEASURE
The integrity of peristalsis, characterized as intact, weak contractions; frequent failed peristalsis; or premature contractions.
RESULTS
Although peristaltic fragments were evident only in patients with type 3 achalasia before treatment, intact, weak, or frequent failed peristalsis was encountered in 5 patients with type 1 (63%), 8 with type 2 (47%), and 4 with type 3 (80%) achalasia after myotomy. One patient with type 3 achalasia had distal esophageal spasm after treatment. In patients with a postmyotomy integrated relaxation pressure of less than 15 mm Hg, only 10 (40%) had persistent absent peristalsis. Panesophageal pressurization disappeared after myotomy in 16 of 19 patients. In the 5 patients with postmyotomy integrated relaxation pressure of more than 15 mm Hg, 4 had weak peristalsis and 1 had absent peristalsis.
CONCLUSIONS AND RELEVANCE
Reduction or normalization of the esophagogastric junction relaxation pressure achieved by myotomy in achalasia is associated with partial recovery of peristalsis in some patients, suggesting that the disease process progresses from the esophagogastric junction to the esophageal body. Whether the return of peristalsis is predictive of an improved therapeutic outcome requires further study.
Topics: Adolescent; Adult; Aged; Esophageal Achalasia; Esophagus; Female; Follow-Up Studies; Humans; Laparoscopy; Male; Manometry; Middle Aged; Peristalsis; Pressure; Recovery of Function; Retrospective Studies; Treatment Outcome; Young Adult
PubMed: 23426591
DOI: 10.1001/2013.jamasurg.38 -
American Journal of Physiology.... Oct 2020High-resolution esophageal manometry (HRM) in its current form assesses only the contraction phase of peristalsis. Degree of esophageal distension ahead of contraction...
High-resolution esophageal manometry (HRM) in its current form assesses only the contraction phase of peristalsis. Degree of esophageal distension ahead of contraction is a surrogate of relaxation and can be measured from intraluminal esophageal impedance measurements. The characteristics of esophageal contractions, i.e., their amplitude, duration, velocity, and modulating factors, have been well studied. We studied the effect of bolus volume and viscosity and posture on swallow-induced distension and contraction and the temporal relationship between the two. HRM impedance recordings of 50 healthy subjects with no esophageal symptoms were analyzed. Eight to ten swallows of 5 and 10 mL of 0.5 N saline and a viscous bolus were recorded in the supine and Trendelenburg positions. Custom-built computer software generated the distension-contraction plots and numerical data of the amplitudes of distension (cross-sectional area) and contraction, and the temporal relationship between distension and peak contraction. The hallmarks of distension waveforms are that ) distension peak, similarly to contraction, travels the esophagus in a peristaltic fashion, and the amplitude of distension increases from the proximal-to-distal direction; ) the amplitude of distension is greater with 10 mL than with 5 mL and greater in Trendelenburg than in supine posture; and ) bolus viscosity increases the amplitude of distension and alters the temporal relationship between distension and contraction waveforms. We describe the characteristics of esophageal distension during peristalsis and the relationship between distension and contraction in a relatively large cohort of normal subjects. These data can be used to compare differences between normal subjects and patients with various esophageal motility disorders in future studies. We studied esophageal distension (surrogate of inhibition) ahead of contraction during peristalsis from intraluminal esophageal impedance measurements. Esophageal distension, similarly to contraction, travels the esophagus in a sequential manner, and the amplitude of esophageal distension increases from proximal to distal direction in the esophagus. Bolus volume, viscosity and posture have significant effects on the amplitude of distension and its temporal relationship with contraction.
Topics: Adult; Aged; Biomechanical Phenomena; Deglutition; Electric Impedance; Esophageal Motility Disorders; Esophagus; Female; Head-Down Tilt; Healthy Volunteers; Humans; Male; Manometry; Middle Aged; Muscle Contraction; Peristalsis; Posture; Supine Position; Viscosity
PubMed: 32755311
DOI: 10.1152/ajpgi.00117.2020 -
Clinical Gastroenterology and... May 2021Achalasia is a disorder of impaired lower esophageal sphincter (LES) relaxation and failed peristalsis traditionally characterized by manometry. As impaired LES...
Achalasia is a disorder of impaired lower esophageal sphincter (LES) relaxation and failed peristalsis traditionally characterized by manometry. As impaired LES relaxation is a mechanism of reduced esophagogastric junction (EGJ) opening, abnormally reduced EGJ distensibility assessed with functional luminal imaging probe (FLIP) was reported among patients with untreated achalasia. Therefore, we aimed to describe the performance characteristics of EGJ opening parameters on FLIP panometry among a large cohort of treatment-naïve achalasia patients.
Topics: Esophageal Achalasia; Esophageal Sphincter, Lower; Esophagogastric Junction; Humans; Manometry; Peristalsis
PubMed: 32289545
DOI: 10.1016/j.cgh.2020.03.069