scholarly journals Circular and longitudinal muscles shortening indicates sliding patterns during peristalsis and transient lower esophageal sphincter relaxation

2015 ◽  
Vol 309 (5) ◽  
pp. G360-G367 ◽  
Author(s):  
Nirali Patel ◽  
Yanfen Jiang ◽  
Ravinder K. Mittal ◽  
Tae Ho Kim ◽  
Melissa Ledgerwood ◽  
...  
Keyword(s):  
Lower Esophageal Sphincter ◽  
Animal Studies ◽  
Longitudinal Muscle ◽  
Circular Muscle ◽  
Esophageal Sphincter ◽  
And Function ◽  
Longitudinal Muscles ◽  
Histology And Immunohistochemistry ◽  
Esophageal Contraction ◽  
Axial Shortening

Esophageal axial shortening is caused by longitudinal muscle (LM) contraction, but circular muscle (CM) may also contribute to axial shortening because of its spiral morphology. The goal of our study was to show patterns of contraction of CM and LM layers during peristalsis and transient lower esophageal sphincter (LES) relaxation (TLESR). In rats, esophageal and LES morphology was assessed by histology and immunohistochemistry, and function with the use of piezo-electric crystals and manometry. Electrical stimulation of the vagus nerve was used to induce esophageal contractions. In 18 healthy subjects, manometry and high frequency intraluminal ultrasound imaging during swallow-induced esophageal contractions and TLESR were evaluated. CM and LM thicknesses were measured (40 swallows and 30 TLESRs) as markers of axial shortening, before and at peak contraction, as well as during TLESRs. Animal studies revealed muscular connections between the LM and CM layers of the LES but not in the esophagus. During vagal stimulated esophageal contraction there was relative movement between the LM and CM. Human studies show that LM-to-CM (LM/CM) thickness ratio at baseline was 1. At the peak of swallow-induced contraction LM/CM ratio decreased significantly (<1), whereas the reverse was the case during TLESR (>2). The pattern of contraction of CM and LM suggests sliding of the two muscles. Furthermore, the sliding patterns are in the opposite direction during peristalsis and TLESR.

Identification of longitudinal muscle activity in opossum lower esophageal sphincter

1991 ◽  
Vol 261 (6) ◽  
pp. G974-G980 ◽  
Author(s):  
S. S. Harrington ◽  
W. J. Dodds ◽  
R. K. Mittal
Keyword(s):  
Muscle Contraction ◽  
Lower Esophageal Sphincter ◽  
Strain Gauge ◽  
Longitudinal Muscle ◽  
Pressure Fluctuations ◽  
Circular Muscle ◽  
Pharmacological Agents ◽  
Esophageal Sphincter ◽  
High Pressure Zone ◽  
Contraction And Relaxation

The aim of this study was to characterize lower esophageal sphincter (LES) longitudinal muscle contraction during changes in LES pressure in opossums. LES pressure was used as a marker of LES circular muscle contraction. Longitudinal muscle contraction was measured by strain gauge transducers. For precise placement of the strain gauge on the LES, the high-pressure zone was identified using a manometric-laser illumination technique. Measurements were made during 1) spontaneous LES pressure fluctuations, 2) LES pressure changes induced by pharmacological agents, and 3) LES relaxation induced by vagal nerve stimulation. These studies show that 1) spontaneous LES pressure fluctuations correlated with spontaneous changes in LES longitudinal muscle contraction; 2) pharmacologically induced contraction and relaxation of LES pressure correlated with contraction and relaxation of LES longitudinal muscle, respectively; 3) a close temporal relationship existed between changes in LES longitudinal muscle contraction and LES pressure that occurred spontaneously or were induced pharmacologically; and 4) vagal stimulation caused LES longitudinal muscle contraction and LES pressure relaxation. We propose that LES longitudinal muscle may play a role in the modulation of intraluminal LES pressure.

scholarly journals Pressure morphology of the relaxed lower esophageal sphincter: the formation and collapse of the phrenic ampulla

2012 ◽  
Vol 302 (3) ◽  
pp. G389-G396 ◽  
Author(s):  
Monika A. Kwiatek ◽  
Frédéric Nicodème ◽  
John E. Pandolfino ◽  
Peter J. Kahrilas
Keyword(s):  
Lower Esophageal Sphincter ◽  
Longitudinal Muscle ◽  
Circular Muscle ◽  
Radial Pressure ◽  
Normal Subjects ◽  
Baseline Length ◽  
Bolus Transit ◽  
Yield Zone ◽  
High Resolution Manometry ◽  
Esophageal Sphincter

This study aimed to apply novel high-resolution manometry with eight-sector radial pressure resolution (3D-HRM technology) to resolve the deglutitive pressure morphology at the esophagogastric junction (EGJ) before, during, and after bolus transit. A hybrid HRM assembly, including a 9-cm-long 3D-HRM array, was used to record EGJ pressure morphology in 15 normal subjects. Concurrent videofluoroscopy was used to relate bolus movement to pressure morphology and EGJ anatomy, aided by an endoclip marking the squamocolumnar junction (SCJ). The contractile deceleration point (CDP) marked the time at which luminal clearance slowed to 1.1 cm/s and the location (4 cm proximal to the elevated SCJ) at which peristalsis terminated. The phrenic ampulla spanned from the CDP to the SCJ. The subsequent radial and axial collapse of the ampulla coincided with the reconstitution of the effaced and elongated lower esophageal sphincter (LES). Following ampullary emptying, the stretched LES (maximum length 4.0 cm) progressively collapsed to its baseline length of 1.9 cm ( P < 0.001). The phrenic ampulla is a transient structure comprised of the stretched, effaced, and axially displaced LES that serves as a “yield zone” to facilitate bolus transfer to the stomach. During ampullary emptying, the LES circular muscle contracts, and longitudinal muscle shortens while that of the adjacent esophagus reelongates. The likely LES elongation with the formation of the ampulla and shortening to its native length after ampullary emptying suggest that reduction in the resting tone of the longitudinal muscle within the LES segment is a previously unrecognized component of LES relaxation.

Gap junctions in gastrointestinal muscle contain multiple connexins

2001 ◽  
Vol 281 (2) ◽  
pp. G533-G543 ◽  
Author(s):  
Y. F. Wang ◽  
E. E. Daniel
Keyword(s):  
Gastrointestinal Tract ◽  
Gap Junctions ◽  
Lower Esophageal Sphincter ◽  
Myenteric Plexus ◽  
Interstitial Cells Of Cajal ◽  
Longitudinal Muscle ◽  
Circular Muscle ◽  
Esophageal Sphincter ◽  
Cells Of Cajal ◽  
Cx 43

In the canine gastrointestinal tract, the roles that gap junctions play in pacemaking and neurotransmission are unclear. Using antibodies to connexin (Cx)43, Cx45, and Cx40, we determined the distribution of these connexins. Cx43 was present in all locations where structural gap junctions occur. Cx40 was also widely distributed in the circular muscle of the lower esophageal sphincter (LES), stomach, and ileum. Cx45 was sparsely distributed in circular muscle of the LES. In the interstitial cells of Cajal (ICC) networks of myenteric plexus, in the deep muscular and submuscular plexuses, sparse Cx45 and Cx40 immunoreactivity was present. In colon, immunoreactivity was found only in the myenteric and submuscular plexus and nearby circular muscle cells. No immunoreactivity was found in sites lacking structural gap junctions (longitudinal muscle, inner circular muscle of the intestine, and most circular muscle of the colon). Studies of colocalization of connexins suggested that in the ICC networks, some colocalization of Cx43 with Cx40 and/or Cx45 occurred. Thus gap junctions in canine intestine may be heterotypic or heteromeric and have different conductance properties in different regions based on different connexin compositions.

scholarly journals Atypical Manometric Abnormality of the Lower Esophageal Sphincter: A Procedure-Related, Stress-Induced Phenomenon?

1995 ◽  
Vol 9 (6) ◽  
pp. 349-351 ◽  
Author(s):  
Bhuvanendram Indrakrishnan ◽  
William G Paterson
Keyword(s):  
Lower Esophageal Sphincter ◽  
Initial Study ◽  
Esophageal Sphincter ◽  
Related Stress ◽  
And Function ◽  
Esophageal Contraction

Stress-induced esophageal contraction abnormalities have been well documented in the literature, but relatively little is known about stress-related lower esophageal sphincter (LES) dysfunction. Two patients are described in whom initial manometry studies revealed LES hypertension and impaired LES relaxation. Both patients were markedly anxious and agitated during the initial study. However, when the manometry was repeated with the patients in a calmer state, LES pressure and function were normal. These cases demonstrate the need to be aware of stress-related LES dysfunction. If this phenomenon is not identified in the appropriate settings, it could lead to significant errors in management.

Neuropeptide Y augments adrenergic contractions at feline lower esophageal sphincter

1989 ◽  
Vol 256 (3) ◽  
pp. G589-G597 ◽  
Author(s):  
H. P. Parkman ◽  
J. C. Reynolds ◽  
C. P. Ogorek ◽  
K. M. Kicsak
Keyword(s):  
Tyrosine Hydroxylase ◽  
Neuropeptide Y ◽  
Lower Esophageal Sphincter ◽  
Longitudinal Muscle ◽  
Circular Muscle ◽  
Gastric Fundus ◽  
Muscularis Mucosa ◽  
Biphasic Effect ◽  
Esophageal Sphincter

The purpose of this study was to determine the anatomic and physiological interactions between neuropeptide Y (NPY) and adrenergic transmitters at the feline lower esophageal sphincter (LES). Intraluminal pressures of the esophagus, LES, and gastric fundus were recorded in anesthetized cats. In a separate group of cats, gastroesophageal junctions were removed after locating the LES manometrically. Adjacent sections were stained with antibodies for NPY and tyrosine hydroxylase (TH). Indirect immunofluorescence revealed staining of TH- and NPY-like immunoreactive (LI) nerves in the circular muscle of the LES. Staining was also present for NPY-LI in longitudinal muscle, muscularis mucosa, periarterial nerves, and nerves and cell bodies of the myenteric plexus of the LES. In vivo, NPY produced a biphasic effect at the LES with an initial contraction (lasting approximately 30 s) followed by a relaxation (lasting approximately 3 min). NPY at the dose giving 50% of the maximum response (10(-6) g/kg) induced a contraction of 14.8 +/- 5.0 mmHg (P less than 0.05) followed by a decrease of basal LES pressure from 29.2 +/- 4.7 to 19.4 +/- 2.9 mmHg (P less than 0.01). Propranolol and phentolamine had no influence on either effect of NPY.(ABSTRACT TRUNCATED AT 250 WORDS)

Asymmetry of lower esophageal sphincter pressure: is it related to the muscle thickness or its shape?

1997 ◽  
Vol 272 (6) ◽  
pp. G1509-G1517 ◽  
Author(s):  
J. Liu ◽  
V. K. Parashar ◽  
R. K. Mittal
Keyword(s):  
Lower Esophageal Sphincter ◽  
Longitudinal Muscle ◽  
Circular Muscle ◽  
Muscle Thickness ◽  
Close Correlation ◽  
Lower Esophageal Sphincter Pressure ◽  
Sphincter Pressure ◽  
Contraction Phase ◽  
Esophageal Sphincter ◽  
Pull Through

Lower esophageal sphincter (LES) pressure shows axial and circumferential asymmetry, the reasons for which are not clear. Our aim was to determine whether the muscle thickness and shape of the LES were the reasons for the axial and circumferential asymmetry in the LES pressure. High-frequency, catheter-based intraluminal ultrasonography was performed to obtain images of the human LES and esophagus. Station pull-through manometry was performed to record the axial and circumferential asymmetry of LES pressure. Circular and longitudinal muscle were thicker in the LES compared with in the esophagus. There was a close correlation between the axial asymmetry in LES pressure and circular muscle thickness. The thickness of LES muscle increased and decreased with an increase and decrease in the LES pressure, respectively. The circumferential asymmetry in resting LES pressure was related to the noncircular shape of the LES. A swallow-induced LES relaxation was followed by its contraction. During the contraction phase, the LES and esophagus showed relative symmetry in pressure and shape. We conclude that the axial asymmetry of LES pressure is explained by its muscle thickness. On the other hand, circumferential asymmetry is related to the noncircular shape of the LES.

scholarly journals Esophageal wall blood perfusion during contraction and transient lower esophageal sphincter relaxation in humans

2012 ◽  
Vol 303 (5) ◽  
pp. G529-G535 ◽  
Author(s):  
Yanfen Jiang ◽  
Valmik Bhargava ◽  
Young Sun Kim ◽  
Ravinder K. Mittal
Keyword(s):  
Lower Esophageal Sphincter ◽  
Longitudinal Muscle ◽  
Blood Perfusion ◽  
Laser Doppler ◽  
Esophageal Wall ◽  
Esophageal Mucosa ◽  
Doppler Probe ◽  
Innovative Technique ◽  
Esophageal Sphincter ◽  
Esophageal Contraction

We recently reported that esophageal contraction reduces esophageal wall perfusion in an animal study. Our aim was to determine esophageal wall blood perfusion (EWBP) during esophageal contraction and transient lower esophageal sphincter relaxations (TLESRs) in humans. We studied 12 healthy volunteers. A custom-designed laser Doppler probe was anchored to the esophageal wall, 4–6 cm above the LES, by use of the Bravo pH system so that the laser light beam stay directed toward the esophageal mucosa. A high-resolution manometry equipped with impedance electrodes recorded esophageal pressures and reflux events. Synchronized pressure, impedance, pH, and EWBP recordings were obtained during dry and wet swallows and following a meal. Stable recordings of laser Doppler EWBP were only recorded when the laser Doppler probe was firmly anchored to the esophageal wall. Esophageal contractions induced by dry and wet swallows resulted in 46 ± 9% and 60 ± 10% reduction in the EWBP, respectively (compared to baseline). Reduction in EWBP was directly related to the amplitude (curvilinear fit) and duration of esophageal contraction. Atropine reduced the esophageal contraction amplitude and decreased the EWBP reduction associated with esophageal contraction. TLESRs were also associated with reduction in the EWBP, albeit of smaller amplitude (29 ± 3%) but longer duration (19 ± 2 s) compared with swallow-induced esophageal contractions. We report 1) an innovative technique to record EWBP for extended time periods in humans and 2) contraction of circular and longitudinal muscle during peristalsis and selective longitudinal muscle contraction during TLESR causes reduction in the EWBP; 3) using our innovative technique, future studies may determine whether esophageal wall ischemia is the cause of esophageal pain/heartburn.

Feline lower esophageal sphincter sling and circular muscles have different functional inhibitory neuronal responses

2006 ◽  
Vol 290 (1) ◽  
pp. G23-G29 ◽  
Author(s):  
Marie-Claude L'Heureux ◽  
Ahmad Muinuddin ◽  
Herbert Y. Gaisano ◽  
Nicholas E. Diamant
Keyword(s):  
Lower Esophageal Sphincter ◽  
Circular Muscle ◽  
Electrical Field Stimulation ◽  
Cholinergic Receptor ◽  
Cholinergic Innervation ◽  
Inhibitory Influence ◽  
Cholinergic Stimulation ◽  
Esophageal Sphincter ◽  
Low Tone ◽  
Resting Tone

The lower esophageal sphincter (LES) has a circular muscle component exhibiting spontaneous tone that is relaxed by nitric oxide (NO) and a low-tone sling muscle that contracts vigorously to cholinergic stimulation but with little or no evidence of NO responsiveness. This study dissected the responses of the sling muscle to nitrergic innervation in relationship to its cholinergic innervation and circular muscle responses. Motor responses were induced by electrical field stimulation (EFS; 1–30 Hz) of muscle strips from sling and circular regions of the feline LES in the presence of cholinergic receptor inhibition (atropine) or NO synthase inhibition [ NG-nitro-l-arginine (l-NNA) ± atropine]. This study showed the following. First, sling muscle developed less intrinsic resting tone compared with circular muscle. Second, with EFS, sling muscle contracted (most at ≤10 Hz), whereas circular muscle relaxed >50% by 5 Hz. Third, on neural blockade with atropine or l-NNA ± atropine, 1) sling muscle, although predominantly influenced by excitatory cholinergic stimulation, had a small neural NO-mediated inhibition, with no significant non-NO-mediated inhibition and 2) circular muscle, although little affected by cholinergic influence, underwent relaxation predominantly by neural release of NO and some non-NO inhibitory influence (at higher EFS frequency). Fourth, the sling, precontracted with bethanecol, could relax with NO and some non-NO inhibition. Finally, the tension range of both muscles is similar. In conclusion, sling muscle has limited NO-mediated inhibition to potentially augment or replace sling relaxation effected by switching off its cholinergic excitation. Differences within the LES sling and circular muscles could provide new directions for therapy of LES disorders.

Esophageal longitudinal muscle contraction: Another component of transient lower esophageal sphincter relaxation (tLESR)?

2001 ◽  
Vol 120 (5) ◽  
pp. A632
Author(s):  
Guoxiang Shi ◽  
John E. Pandolfino ◽  
Raymond J. Joehl ◽  
James G. Brassuer ◽  
Peter J. Kahrilas
Keyword(s):  
Muscle Contraction ◽  
Lower Esophageal Sphincter ◽  
Longitudinal Muscle ◽  
Lower Esophageal Sphincter Relaxation ◽  
Esophageal Sphincter

IL-1β signaling in cat lower esophageal sphincter circular muscle

2006 ◽  
Vol 291 (4) ◽  
pp. G672-G680 ◽  
Author(s):  
Weibiao Cao ◽  
Ling Cheng ◽  
Jose Behar ◽  
Piero Biancani ◽  
Karen M. Harnett
Keyword(s):  
Lower Esophageal Sphincter ◽  
P38 Mapk ◽  
Circular Muscle ◽  
Circular Smooth Muscle ◽  
Sequential Activation ◽  
Cox 2 ◽  
Esophageal Sphincter ◽  
Sb 203580

In a cat model of acute experimental esophagitis, resting in vivo lower esophageal sphincter (LES) pressure and in vitro tone are lower than in normal LES, and the LES circular smooth muscle layer contains elevated levels of IL-1β that decrease the LES tone of normal cats. We now examined the mechanisms of IL-1β-induced reduction in LES tone. IL-1β significantly reduced acetylcholine-induced Ca2+ release in Ca2+-free medium, and this effect was partially reversed by catalase, demonstrating a role of H2O2 in these changes. IL-1β significantly increased the production of H2O2, and the increase was blocked by the p38 MAPK inhibitor SB-203580, by the cytosolic phospholipase A2 (cPLA2) inhibitor AACOCF3, and by the NADPH oxidase inhibitor apocynin, but not by the MEK1 inhibitor PD-98059. IL-1β significantly increased the phosphorylation of p38 MAPK and cPLA2. IL-1β-induced cPLA2 phosphorylation was blocked by SB-203580 but not by AACOCF3, suggesting sequential activation of p38 MAPK-phosphorylating cPLA2. The IL-1β-induced reduction in LES tone was partially reversed by AACOCF3 and by the Ca2+-insensitive PLA2 inhibitor bromoenol lactone (BEL). IL-1β significantly increased cyclooxygenase (COX)-2 and PGE2 levels. The increase in PGE2 was blocked by SB-203580, AACOCF3, BEL, and the COX-2 inhibitor NS-398 but not by PD-98059 or the COX-1 inhibitor valeryl salicylate. The data suggested that IL-1β reduces LES tone by producing H2O2, which may affect Ca2+-release mechanisms and increase the synthesis of COX-2 and PGE2. Both H2O2 and PGE2 production depend on sequential activation of p38 MAPK and cPLA2. cPLA2 activates NADPH oxidases, producing H2O2, and may produce arachidonic acid, converted to PGE2 via COX-2.

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