Lower Esophageal Sphincter Motility Research Articles

Arecae pericarpium extract induces porcine lower-esophageal-sphincter contraction via muscarinic receptors

BackgroundGastroesophageal reflux disease (GERD) is associated with lower esophageal sphincter (LES) incompetence. In some patients, GERD is refractory to acid reduction therapy which is the main treatment for GERD. So far, medications that can increase LES tone are few. Arecae pericarpium (A. pericarpium) is a medication in Traditional Chinese Medicine known to promote intestinal motility.MethodsWe investigated the effect of A. pericarpium extracts on porcine LES motility. In addition, we used tetrodotoxin (TTX) and atropine to study the underlying mechanism of A. pericarpium extracts-induced contractions of LES.ResultsThe results of this study showed that A. pericarpium extracts and their main active ingredient, arecoline, can induce the contractions of porcine LES sling and clasp muscles in a dose-response manner. TTX did not have an inhibitory effect on the contractions induced by A. pericarpium extracts and arecoline in LES. However, atropine significantly inhibited A. pericarpium extracts- and arecoline-induced contractions of LES.ConclusionA. pericarpium extracts can induce the contractions of porcine LES in a dose dependent manner, possibly through muscarinic receptors, and hence, may be worth developing as an alternative therapy for GERD.

Long-Chain Fatty Acid Receptors Mediate Relaxation of the Porcine Lower Esophageal Sphincter.

Long-chain fatty acids activate the free fatty acid receptor 1 (FFA1) and FFA4. In the gastrointestinal system, FFA1 and FFA4 have been found in the pancreas and intestine. Fatty food and decreased lower esophageal sphincter (LES) motility are associated with gastroesophageal reflux disease. The effect of long-chain fatty acids on the esophageal motility is unknown. The purpose of this study is to investigate the effects of long-chain fatty acids on the porcine LES motility ex vivo using isometric transducers. In endothelin 1-precontracted porcine LES strips, the FFA1 selective agonists, fasiglifam, TUG424, and GW9508, caused marked relaxations in a concentration-dependent manner. The relative efficacies to elicit relaxation were GW9508 > TUG424 > fasiglifam in both clasp and sling strips. In contrast, the FFA4 specific agonists, TUG891 and GSK137647, produced mild relaxations. In addition, the endogenous FFA1 agonist DHA caused a mild relaxation whereas GW1100, an FFA1 antagonist, inhibited GW9508 induced relaxation of the porcine LES clasp and sling muscle. Both real-time PCR and immunohistochemistry revealed that FFA1 and FFA4 were expressed in the porcine LES. Real-time PCR analysis showed that the FFA4 expression was much lower than FFA1. Taken together, long-chain fatty acid receptor agonists elicit relaxation of the porcine LES. FFA1 might influence LES motility.

Estradiol mediates relaxation of porcine lower esophageal sphincter

Most pregnant women have symptoms of gastroesophageal reflux disease (GERD) during pregnancy. Postmenopausal hormone replacement therapy is associated with GERD. The effects of estradiol on lower esophageal sphincter (LES) motility and GERD are not clearly known. The purpose of this study is to investigate the effects of estradiol on the motility of the porcine LES. Relaxations of clasp and sling strips of porcine LES caused by estradiol were measured using isometric transducers. We investigated the mechanism of estradiol-induced relaxation of the porcine LES using tetraethylammonium, apamine, iberiotoxin, glibenclamide, KT5720, KT5823, NG-nitro-l-arginine, tetrodotoxin, and ω-conotoxin GVIA. Reverse transcription polymerase chain reaction (PCR) analysis and immunohistochemistry (IHC) were performed to determine the existence of the G protein-coupled estrogen receptor (GPER) in the porcine LES. In endothelin-1-precontracted porcine LES strips, estradiol caused marked relaxations in a concentration-dependent manner. The mechanism of estradiol-induced relaxation on the porcine LES was associated with the potassium channel. Reverse transcription PCR analysis and IHC revealed that GPER was expressed in the sling and clasp fibers of the porcine LES. This finding suggests that GPER mediates the relaxation of the porcine LES. Estradiol may play a role in LES motility.

PREOPERATIVE MANOMETRY FOR THE SELECTION OF OBESE PEOPLE CANDIDATE TO SLEEVE GASTRECTOMY.

ABSTRACT Background:Sleeve gastrectomy may alter esophageal motility and lower esophageal sphincter pressure. Aim:To detect manometric changings in the esophagus and lower esophageal sphincter before and after sleeve gastrectomy in order to select patients who could develop postoperative esophageal motilitity disorders and lower esophageal sphincter pressure modifications. Methods:Seventy-three patients were selected. All were submitted to manometry before the operation and one year after. The variables analyzed were: resting pressure of the lower esophageal sphincter, contraction wave amplitude, duration of contraction waves, and esophageal peristalsis. Data were compared before and after surgery and to the healthy and non-obese control group. Exclusion criteria were: previous gastric surgery, reflux symptoms or endoscopic findings of reflux or hiatal hernia, diabetes and use of medications that could affect esophageal or lower esophageal sphincter motility. Results:49% of the patients presented preoperative manometric alterations: lower esophageal sphincter hypertonia in 47%, lower esophageal sphincter hypotonia in 22% and increase in contraction wave amplitude in 31%. One year after surgery, manometry was altered in 85% of patients: lower esophageal sphincter hypertonia in 11%, lower esophageal sphincter hypotonia in 52%, increase in contraction wave amplitude in 27% and 10% with alteration in esophageal peristalsis. Comparing the results between the preoperative and postoperative periods, was found statistical significance for the variables of the lower esophageal sphincter, amplitude of contraction waves and peristalsis. Conclusion:Manometry in the preoperative period of sleeve gastrectomy is not an exam to select candidates to this technique.

Esophageal Motility and Rikkunshito Treatment for Proton Pump Inhibitor-Refractory Nonerosive Reflux Disease: A Prospective, Uncontrolled, Open-Label Pilot Study Trial

BackgroundOnly a few reports focused on esophageal motility in patients with proton pump inhibitor (PPI)-refractory nonerosive reflux disease (NERD) and there has been no established strategy for treatment. ObjectiveTo clarify the characteristics of esophageal motility in patients with PPI-refractory NERD, we evaluated esophageal function using combined multichannel intraluminal impedance and esophageal manometry (MII-EM). In addition, we evaluated the efficacy of rikkunshito (RKT), which is a gastrointestinal prokinetic agent. MethodsThirty patients with NERD were enrolled and underwent MII-EM. After 8 weeks of RKT (7.5 g/d) treatment, MII-EM was repeated on patients with PPI-refractory NERD. Symptoms were assessed by the Gastrointestinal Symptom Rating Scale. ResultsIn patients with PPI-refractory NERD, measures of complete bolus transit, peristaltic contractions, and residual pressure of the lower esophageal sphincter during swallowing deviated from the standard values and esophageal clearance was found to be deteriorated. RKT significantly improved the peristaltic contractions (P < 0.05), the complete bolus transit (P < 0.01), and the residual pressure of lower esophageal sphincter (P < 0.05) in these patients. The overall score (P < 0.01) and the subscale scores of acid reflux syndrome (P < 0.05), abdominal pain (P < 0.05), and indigestion syndrome (P < 0.01) in the Gastrointestinal Symptom Rating Scale were significantly improved by the 8-week RKT treatment. ConclusionsIn the pilot study, patients with PPI-refractory NERD had disorders of esophageal and lower esophageal sphincter motility that were improved by RKT. Further studies examining esophageal motor activity of RKT in PPI-refractory NERD are required. University hospital Medical Information Network (UMIN) Clinical Trial Registry identifier: UMIN000003092.

A catheter-based acoustic interrogation device for monitoring motility dynamics of the lower esophageal sphincter.

This paper presents novel minimally-invasive, catheter-based acoustic interrogation device for monitoring motility dynamics of the lower esophageal sphincter (LES). A micro-oscillator actively emitting sound wave at 16 kHz is located at one side of the LES, and a miniature microphone is located at the other side of the sphincter to capture the sound generated from the oscillator. Thus, the dynamics of the opening and closing of the LES can be quantitatively assessed. In this paper, experiments are conducted utilizing an LES motility dynamics simulator. The sound strength is captured by the microphone and is correlated to the level of LES opening and closing controlled by the simulator. Measurements from the simulator model show statistically significant (p < 0.05) Pearson correlation coefficients (0.905 on the average in quiet environment and 0.736 on the average in noisy environment, D.O.F. = 9). Measuring the level of LES opening and closing has the potential to become a valuable diagnostic technique for understanding LES dysfunction and the disorders associated with it.

P-0021 - The Effect of Cancer Stomach on the Lower Oesophageal Sphincter Motility

P-0021 - The Effect of Cancer Stomach on the Lower Oesophageal Sphincter Motility

Bile acids cause relaxation of the lower esophageal sphincter through G-protein-coupled bile acid receptors

ObjectivesBile acids inhibit contraction of the gallbladder and intestine through the G-protein-coupled bile acid receptor (GPBAR). Perfusion of the esophagus with bile and acid (HCl) decreases lower esophageal sphincter (LES) pressure. The effects of bile acids on LES motility are not clear. The purpose of the present study was to investigate the effects of bile acids on LES motility in vitro. Materials and MethodsWe measured the relaxation of muscle strips isolated from guinea pig and rat LES caused by bile acids or the selective GPBAR agonist RG-239. Reverse transcription polymerase chain reaction (RT-PCR) was performed to determine GPBAR expression in rat LES. ResultsIn carbachol-contracted guinea pig LES strips, lithocholic acid (LCA), deoxycholic acid (DCA), chenodeoxycholic acid (CDCA), and cholic acid (CA) produced relaxation in a concentration-dependent manner. The relative potency was LCA ≥ DCA > CDCA > CA. RG-239 also induced concentration-dependent relaxation. This suggests that GPBAR mediates relaxation in guinea pig LES. DCA-induced LES relaxation was attenuated by the protein kinase A inhibitor KT 5720 but not by the protein kinase G inhibitor KT 5823 or the NO synthase inhibitor L-NNA. This suggests the involvement of cAMP. Separately, in endothelin-1-contracted rat LES strips, bile acids induced relaxation. The relative potency was LCA = DCA > CDCA > CA. RT-PCR revealed GPBAR expression in rat LES. ConclusionThese results demonstrate that bile acids cause relaxation of guinea pig and rat LES through GPBAR.

M2046 Bile Acids Cause Relaxation of Lower Esophageal Sphincter Through G Protein-Coupled Bile Acid Receptors

Objectives: Bile acids inhibit contraction of the gallbladder and intestine through the G-protein-coupled bile acid receptor (GPBAR). Perfusion of the esophagus with bile and acid (HCl) decreases lower esophageal sphincter (LES) pressure. The effects of bile acids on LES motility are not clear. The purpose of the present study was to investigate the effects of bile acids on LES motility in vitro. Materials and Methods: We measured the relaxation of muscle strips isolated from guinea pig and rat LES caused by bile acids or the selective GPBAR agonist RG-239. Reverse transcription polymerase chain reaction (RT-PCR) was performed to determine GPBAR expression in rat LES. Results: In carbachol-contracted guinea pig LES strips, lithocholic acid (LCA), deoxycholic acid (DCA), chenodeoxycholic acid (CDCA), and cholic acid (CA) produced relaxation in a concentration-dependent

M1877 Two Functional Categories of Reflux-Inhibiting GABA B Receptor Agonists Defined By Their Affinity for the GABA Transporter

Background: Proton pump inhibitors (PPI) are the drug of first choice for treating patients with gastroesophageal reflux disease (GERD). However, about 50% of non-erosive reflux disease (NERD) patients have a poor response to PPI treatment. It is reported that esophageal motility disorder involving a decline in esophageal clearance contributes to the poor PPI response. Accordingly, a drug capable of enhancing esophageal motility would be beneficial in the treatment of NERD patients. Rikkunshito, a gastrointestinal prokinetic agent, is known to improve esophageal clearance in GERD patients and gastric emptying in functional dyspepsia patients and to increase secretion of ghrelin in rats. Aim: To clarify the efficacy of rikkunshito in NERD patients, we evaluated the effects of rikkunshito on esophageal and lower esophageal sphincter (LES) motility and symptoms. Methods: Fifteen patients were enrolled in the study. They were diagnosed as having NERD according to endoscopic testing and the score (6 points or more) obtained on the questionnaire for the diagnosis of reflux disease (QUEST). All patients stopped taking all gastrointestinal-related drugs for over 1 week prior to rikkunshito treatment, and were administered rikkunshito (7.5 g per day, orally) for 8 weeks. Esophageal and LES functions during liquid or semisolid swallow were evaluated using MII-EM following gold standard methods before and after rikkunshitotreatment. Symptoms were assessed using the Gastrointestinal Symptom Rating Scale (GSRS) before, 4 weeks after, and 8 weeks after treatment. Results: Rikkunshito-treatment significantly improved the mean of complete bolus transit (CBT) during liquid or semisolid swallow from 60.7±7.7% to 90.0±5.8% (p 79%, semisolid: >69%) for CBT decreased from 53.3% to 16.7% and from 60.0% to 33.3% after treatment, respectively. In manometry evaluation, rikkunshito significantly improved the mean of LES residual pressure during liquid swallow from 6.0±1.3 mmHg to 3.8±1.4 mmHg (p<0.05). In addition, rikkunshito significantly ameliorated total GI symptom scores in GSRS (from 2.1±0.2 to 1.6±0.1: (p<0.05)) and showed a tendency toward improvement of subscales for reflux symptoms, abdominal pain and dyspeptic symptoms. Conclusion: We found that rikkunshito improved the esophageal clearance and symptoms in NERD patients through the amelioration of esophageal and LES motility disorder. Thus, rikkunshito may become a useful drug for treating NERD patients.

M1876 Rikkunshito Improves Esophageal Motility Disorder and Symptoms in Patients with NERD - a Study Using Combined Multichannel Intraluminal Impedance and Manometry (MII-EM) -

Background: Proton pump inhibitors (PPI) are the drug of first choice for treating patients with gastroesophageal reflux disease (GERD). However, about 50% of non-erosive reflux disease (NERD) patients have a poor response to PPI treatment. It is reported that esophageal motility disorder involving a decline in esophageal clearance contributes to the poor PPI response. Accordingly, a drug capable of enhancing esophageal motility would be beneficial in the treatment of NERD patients. Rikkunshito, a gastrointestinal prokinetic agent, is known to improve esophageal clearance in GERD patients and gastric emptying in functional dyspepsia patients and to increase secretion of ghrelin in rats. Aim: To clarify the efficacy of rikkunshito in NERD patients, we evaluated the effects of rikkunshito on esophageal and lower esophageal sphincter (LES) motility and symptoms. Methods: Fifteen patients were enrolled in the study. They were diagnosed as having NERD according to endoscopic testing and the score (6 points or more) obtained on the questionnaire for the diagnosis of reflux disease (QUEST). All patients stopped taking all gastrointestinal-related drugs for over 1 week prior to rikkunshito treatment, and were administered rikkunshito (7.5 g per day, orally) for 8 weeks. Esophageal and LES functions during liquid or semisolid swallow were evaluated using MII-EM following gold standard methods before and after rikkunshitotreatment. Symptoms were assessed using the Gastrointestinal Symptom Rating Scale (GSRS) before, 4 weeks after, and 8 weeks after treatment. Results: Rikkunshito-treatment significantly improved the mean of complete bolus transit (CBT) during liquid or semisolid swallow from 60.7±7.7% to 90.0±5.8% (p 79%, semisolid: >69%) for CBT decreased from 53.3% to 16.7% and from 60.0% to 33.3% after treatment, respectively. In manometry evaluation, rikkunshito significantly improved the mean of LES residual pressure during liquid swallow from 6.0±1.3 mmHg to 3.8±1.4 mmHg (p<0.05). In addition, rikkunshito significantly ameliorated total GI symptom scores in GSRS (from 2.1±0.2 to 1.6±0.1: (p<0.05)) and showed a tendency toward improvement of subscales for reflux symptoms, abdominal pain and dyspeptic symptoms. Conclusion: We found that rikkunshito improved the esophageal clearance and symptoms in NERD patients through the amelioration of esophageal and LES motility disorder. Thus, rikkunshito may become a useful drug for treating NERD patients.

M1878 The Novel 5-HT4 Receptor Partial Agonist RQ-00000010 Enhances a Rate of Gastric Emptying in Dog Without QT Interval Prolongation

Background: Proton pump inhibitors (PPI) are the drug of first choice for treating patients with gastroesophageal reflux disease (GERD). However, about 50% of non-erosive reflux disease (NERD) patients have a poor response to PPI treatment. It is reported that esophageal motility disorder involving a decline in esophageal clearance contributes to the poor PPI response. Accordingly, a drug capable of enhancing esophageal motility would be beneficial in the treatment of NERD patients. Rikkunshito, a gastrointestinal prokinetic agent, is known to improve esophageal clearance in GERD patients and gastric emptying in functional dyspepsia patients and to increase secretion of ghrelin in rats. Aim: To clarify the efficacy of rikkunshito in NERD patients, we evaluated the effects of rikkunshito on esophageal and lower esophageal sphincter (LES) motility and symptoms. Methods: Fifteen patients were enrolled in the study. They were diagnosed as having NERD according to endoscopic testing and the score (6 points or more) obtained on the questionnaire for the diagnosis of reflux disease (QUEST). All patients stopped taking all gastrointestinal-related drugs for over 1 week prior to rikkunshito treatment, and were administered rikkunshito (7.5 g per day, orally) for 8 weeks. Esophageal and LES functions during liquid or semisolid swallow were evaluated using MII-EM following gold standard methods before and after rikkunshitotreatment. Symptoms were assessed using the Gastrointestinal Symptom Rating Scale (GSRS) before, 4 weeks after, and 8 weeks after treatment. Results: Rikkunshito-treatment significantly improved the mean of complete bolus transit (CBT) during liquid or semisolid swallow from 60.7±7.7% to 90.0±5.8% (p 79%, semisolid: >69%) for CBT decreased from 53.3% to 16.7% and from 60.0% to 33.3% after treatment, respectively. In manometry evaluation, rikkunshito significantly improved the mean of LES residual pressure during liquid swallow from 6.0±1.3 mmHg to 3.8±1.4 mmHg (p<0.05). In addition, rikkunshito significantly ameliorated total GI symptom scores in GSRS (from 2.1±0.2 to 1.6±0.1: (p<0.05)) and showed a tendency toward improvement of subscales for reflux symptoms, abdominal pain and dyspeptic symptoms. Conclusion: We found that rikkunshito improved the esophageal clearance and symptoms in NERD patients through the amelioration of esophageal and LES motility disorder. Thus, rikkunshito may become a useful drug for treating NERD patients.

American Gastroenterological Association Institute Technical Review on the Management of Gastroesophageal Reflux Disease

American Gastroenterological Association Institute Technical Review on the Management of Gastroesophageal Reflux Disease

Effect of baclofen on oesophageal motility and transient lower oesophageal sphincter relaxations in GORD patients: a 48‐h manometric study

Little is known about prolonged effect of baclofen on oesophageal and lower oesophageal sphincter (LOS) motility. We aimed at investigating the oesophageal motility in gastro-oesophageal reflux disease (GORD) patients 24 h before and after the administration of multiple doses of baclofen. Twenty-one GORD patients underwent a 48-h manometry recording the swallows, the oesophageal and the LOS motility. During the second 24-h period, patients received baclofen 10 mg or placebo four times per day in a double-blind randomized fashion. Baclofen increased the LOS basal tone in comparison with baseline (P = 0.02), with a concomitant reduction in the number of transient LOS relaxations (TLOSRs) (P = 0.01). Moreover, baclofen induced a decrease of the swallows (P = 0.02) and of primary oesophageal body waves (P = 0.04) with no changes in the amplitude. Multiple doses of baclofen determine a reduction in the number of TLOSRs and an increase in the LOS tone throughout the 24 h. The concomitant decreased number of swallows and of primary peristalsis could depend on the well-known lower amount of reflux episodes induced by the drug. The potential therapeutic effect of baclofen could be expressed not only postprandially, but also in the fasting state when reflux episodes are present as well.

Mechanisms controlling function in the clasp and sling regions of porcine lower oesophageal sphincter

Characterization of functional differences between lower oesophageal sphincter (LOS) clasp and sling muscles might aid the development of more specific pharmacological and surgical approaches for the treatment of motility disorders. Circular LOS strips from 25 adult pigs were studied in organ baths to compare the physiology of clasp and sling fibres. Sling strips developed greater tone than clasp fibres (mean(s.e.m.) 7.59(0.89) versus 4.72(0.67) g; P = 0.017). LOS tone was more dependent on extracellular calcium in clasp strips and on the activity of cholinergic enteric motor neurones (EMNs) in sling strips. The amplitude of maximal relaxation caused by electrical field stimulation (EFS, 3Hz) of EMNs was greater in clasp strips (mean(s.e.m.) 74.5(2.3) versus 58.1(2.2) per cent of tone; P < 0.001). EFS-induced relaxation was reduced in clasp fibres and fully blocked in sling fibres by nitrergic blockade with 10 micromol/l 1H-[1,2,4]oxadiazole-[4,3-alpha]quinoxalin-1-one (ODQ). The amplitude of EFS cholinergic responses was significantly greater in sling fibres. In the clasp region, relaxation caused by stimulation of EMNs with 100 micromol/l nicotine was reduced by ODQ. In sling fibres, nicotine induced relaxation at rest and cholinergic contraction following ODQ. Clasp and sling fibres of the porcine LOS show marked intrinsic functional differences. This should be considered when developing more specific approaches to human LOS motility disorders.

The effect of laparoscopic partial fundoplication on dysphagia, esophageal and lower esophageal sphincter motility

It has been suggested that dysphagia is less common after partial versus complete fundoplication. The mechanisms contributing to postoperative dysphagia remain unclear. The objective of the present prospective study was to investigate esophageal motility and the prevalence of dysphagia in patients who have undergone laparoscopic partial fundoplication. Symptoms, lower esophageal sphincter (LES) characteristics and esophageal body motility were evaluated prospectively in 62 patients before and after laparoscopic partial fundoplication: 33 women and 29 men with a mean age of 44 +/- 1.5 years (range, 21-71). The patients filled in symptom questionnaires and underwent stationary and ambulatory manometry and 24-h pH-metry before and after operation. A small but significant increase in LES pressure from 14.8 +/- 0.9 to 17.8 +/- 0.8 mmHg was seen after laparoscopic partial fundoplication. Further, LES characteristics and esophageal body motility were not different post- versus preoperation. Three months after surgery, dysphagia was present in eight patients. No differences in LES characteristics or body motility were present between patients with and without dysphagia. Six months after the operation dysphagia was present in only three patients (3.2% mild and 1.6% severe dysphagia). Adequate reflux control was obtained in 85% of the patients. Laparoscopic partial fundoplication offers adequate reflux control without affecting esophageal body motility and with a very low incidence of postoperative dysphagia.

Effects of bronchial obstruction on lower esophageal sphincter motility and gastroesophageal reflux in patients with asthma.

The relationship between gastroesophageal reflux and asthma remains unclear. The aim of this study was to analyze the effect of bronchial obstruction on lower esophageal sphincter (LES) motility and reflux in patients with asthma. LES motility and esophageal pH were assessed in eight subjects with intermittent asthma and eight healthy volunteers during three consecutive 30-minute periods: baseline, methacholine-induced bronchospasm, and after inhalation of the beta2-agonist salbutamol. Healthy subjects inhaled 2 mg of methacholine, whereas subjects with asthma inhaled the dose of methacholine causing a 15% fall in FEV(1), as determined by a previous methacholine challenge. LES motility, esophageal pH, and FEV(1) were not significantly different between the three periods in healthy subjects. In patients with asthma, methacholine induced a 21.9 +/- 2.6% decrease in FEV(1) and a concomitant increase in the rate of transient LES relaxation (TLESR) and reflux episodes. Inhalation of salbutamol decreased the rate of TLESRs but not the number of reflux episodes. We conclude that in patients with asthma, methacholine-induced bronchospasm increases the rate of TLESR and the number of reflux episodes. These results support the belief that, in asthma, bronchial obstruction may be responsible for reflux or may aggravate reflux through a mechanism that remains to be further clarified.

Transient lower oesophageal sphincter relaxations play an insignificant role in gastro-oesophageal reflux to the proximal oesophagus.

Gastro-oesophageal reflux to the proximal oesophagus may cause atypical symptoms of gastro-oesophageal reflux disease (GORD). The motor abnormalities underlying reflux into the proximal oesophagus are still unclear. The aim of this study was to analyse the oesophageal motility during reflux into the proximal oesophagus in a group of healthy subjects and in patients with atypical symptoms of GORD. We concentrated particularly on lower oesophageal sphincter (LOS) activity and transient lower oesophageal sphincter relaxations (TLOSRs). Ten patients (7M, 3F, age 25-51 years) with mild oesophagitis (Savary-Miller grade I-II) and 10 healthy subjects (6M, 4F, age 23-54 years) underwent a 24-h dual pH-metric and manometric recording, using an electronic portable device. This recorded distal and proximal oesophageal pH values, oesophageal body and LOS motility. GORD patients had more distal and proximal reflux (DR and PR) compared with healthy controls (DR P < 0.001; PR P < 0.05). TLOSRs were the most frequent event during reflux into the distal oesophagus, whereas TLOSR frequency was much lower during reflux to the proximal oesophagus in GORD patients and in healthy controls (P < 0.05 and P < 0.01 vs. distal reflux, respectively). A significant relationship between TLOSRs and distal refluxes was present but no relationship with proximal reflux was detected. We conclude that TLOSRs are much less frequent during reflux to the proximal oesophagus than distal oesophageal reflux in patients with mild GORD suffering from atypical manifestations. The mechanism of acid reflux to the proximal oesophagus is unclear.

H. pylori and transient lower esophageal sphincter relaxations induced by gastric distension in healthy humans

The role of Helicobacter pylori infection in the control of lower esophageal sphincter (LES) motility, especially the occurrence of transient LES relaxations (TLESRs), was studied in eight H. pylori-positive and eight H. pylori-negative healthy subjects. During endoscopy, biopsy specimens were taken from the cardia, fundus, and antrum for determinations of H. pylori status, gastritis, and proinflammatory cytokine mucosal concentrations. LES motility was monitored during three different 30-min periods: baseline, gastric distension (barostat), and gastric distension with CCK infusion. Gastric distension significantly increased the TLESR rate, whereas CCK increased the rate of distension-induced TLESRs further and reduced resting LES pressure without significant differences between infected and noninfected subjects. H. pylori status did not influence resting LES pressure or gastric compliance. Cytokine mucosal concentrations were increased in infected patients, but no correlation was found with the TLESR rate, which was also independent of inflammation at the cardia, fundus, and antrum. These results suggest that H. pylori-associated inflammation does not affect the motor events involved in the pathogenesis of gastroesophageal reflux.

Effect of low and high fat meals on lower esophageal sphincter motility and gastroesophageal reflux in healthy subjects

OBJECTIVE: The reported effects of fatty meals on lower esophageal sphincter pressure (LESP) and gastroesophageal reflux (GER) are controversial. Therefore, the aim of the present study was to reevaluate the effect of isocaloric and isovolumetric low and high fat meals on LESP and GER. METHODS: Twelve healthy volunteers (six women, six men, 19 to 31 yr) received an isocaloric (842 kcal) solid–liquid (310 ml with 260 kcal) meal with either a low (10% fat, 14% proteins, 76% carbohydrates) or a high fat content (50% fat, 18% proteins, 32% carbohydrates) in a randomized, double-blinded fashion. The nutritional composition was identical for the solid and liquid part of the meals. In the first postprandial hour LESP was recorded continuously using a Dent sleeve, and esophageal pH measurement was performed for 3 h postprandially with a glass electrode. We calculated the mean LESP, the frequency of transient LES relaxations (TLESR) and of reflux episodes (RE), the percentage of TLESR with GER, and the fraction time pH <4. RESULTS: For all parameters measured no difference was observed between the low and the high fat meal. Mean LESP amounted to a median of 10.7 mm Hg (range, 7.3 to 15.1 mm Hg) after the low fat meal and to 11.1 mm Hg (5.2 to 16.3 mm Hg) after the high fat meal. The frequency of TLESR (n/1 h) rated to 9 (5 to 13) and 8 (4 to 14), and of RE (n/3 h) to 12 (3 to 22) and 11 (1 to 30). The percentage of TLESR with GER were 37% (0 to 100) and 30% (0 to 78). The fraction time pH <4 amounted to 2.3% (0.2 to 23.7) and 1.8% (0.1 to 28.8) after the low and high fat meal, respectively. CONCLUSIONS: In healthy volunteers no difference in postprandial LESP and GER was seen after a high fat meal compared with an isocaloric and isovolumetric low fat meal. Our results suggest that it is inappropriate to advise GER patients to reduce the fat content of their meals for symptom relief.