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Myoelectrical Activity (myoelectrical + activity)

Distribution by Scientific Domains

Medical Sciences	100%

Kinds of Myoelectrical Activity

gastric myoelectrical activity

Selected Abstracts

The Chinese herbal preparation Qing Yi Tang (QYT) improves intestinal myoelectrical activity and Increases intestinal transit during acute pancreatitis in Rodents

PHYTOTHERAPY RESEARCH, Issue 4 2007
Yong-Yu Li
Abstract The aim was to investigate alterations of intestinal motility in models of acute pancreatitis and to investigate the effects of the Chinese herbal preparation Qing Yi Tang (QYT) on these alterations. Upper gastrointestinal transit was evaluated in mice following induction of mild acute pancreatitis (MAP) using caerulein. Myoelectrical activity was recorded in rats after induction of severe acute pancreatitis (SAP) using sodium deoxycholate (SDOC). The contractility of jejunum segments was evaluated in the presence of SDOC, lipopolysaccharide (LPS) and trypsin. QYT accelerated the transit in MAP mice in a concentration dependent manner. Slow wave activity of smooth muscle in rat stomach and jejunum remained unchanged following SAP, but the spiking activity was significantly decreased, with bursts of 7.2 ± 2.6/10 min compared with 47.9 ± 13.2/10 min without SAP (p < 0.01). QYT reversed this decrease. Additionally, the amplitudes of slow waves and spikes were enhanced by QYT in SAP rats. The tension and amplitude of spontaneous contractile activity was reduced by SDOC and LPS and increased by trypsin. Gastrointestinal (GI) transit is altered by SAP but not by MAP. The Chinese herbal preparation QYT improves disturbed motility in AP by stimulating myoelectrical activity and accelerating GI transit. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Gastric myoelectrical activity post-chemoradiotherapy and esophagectomy: a prospective study using subscapular surface recording

DISEASES OF THE ESOPHAGUS, Issue 1 2004
P. M. Lawlor
SUMMARY., The aims of this study were to prospectively evaluate gastric function in esophageal cancer patients after chemoradiotherapy and following surgery, using cutaneous electrogastrography (EGG). Twenty-three patients with esophageal adenocarcinoma were recruited to the study. A subset of patients (n = 11) underwent neoadjuvant chemoradiotherapy and were also studied at 14 days after treatment. All patients underwent EGG studies prior to and following surgery, at 3 months postoperatively. Ten of these patients were also studied at medians of 6 months and 12 months after surgery. Twenty normal volunteers were used as controls. Post-operative EGG studies were monitored with a modified technique; the electrodes being placed in the subscapular region in the area of the transposed stomach. Following neoadjuvant treatment there was a significant increase in abnormal gastric myoelectrical activity involving changes in tachygastrias and decreased motility as measured by power ratio. Post-operatively there was a significant increase in bradygastria which persisted at 6 months but not at 12 months. There was a corresponding decrease in normogastria which persisted at 6 months and to a lesser extent at 12 months. Dominant frequency remained significantly depressed at 3, 6 and 12 months. Gastric myoelectrical activity is normal in untreated esophageal cancer. Neoadjuvant chemoradiotherapy causes a disruption to normal myoelectrical activity involving reduced motility and tachygastrias. Surgery causes a depression in dominant frequency with a reduced incidence of normogastria at 3 months and 6 months but with a tendency towards normality at 12 months. [source]

Effects of audio stimulation on gastric myoelectrical activity and sympathovagal balance in healthy adolescents and adults

JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 1 2008
Dennis D Chen
Abstract Aim:, The primary aim of this study was to investigate the effects of different audio stimulations on gastric myoelectrical activity and sympathovagal balance in adolescents compared with adults. Methods:, The study was performed in 11 adults and 12 adolescents. Each subject underwent two sessions, one for classical music, and the other for noise. Each session consisted of 30 min of baseline, 30 min of fasting audio stimulation, a test meal, 30 min of fed audio stimulation, and 30 min of recovery. Electrocardiogram and electrogastrogram were both recorded throughout each session. Results:, (i) In the fasting state, both classical music and noise impaired gastric slow wave activity in adolescents. In adults, noise had no effects while classical music moderately improved slow wave rhythmicity. (ii) In the fed state, neither noise nor music had any effects on gastric slow waves. (iii) In the fasting state, both noise and music increased the sympathovagal balance in adolescents; in adults only noise had such an effect. (iv) The test meal increased the sympathovagal balance in all groups. Conclusions:, Gastric slow waves and the sympathovagal balance are more strongly affected by audio stimulation in adolescents than in adults. The test meal normalizes the audio stimulation-induced differences between the groups. [source]

Effects and probable mechanisms of electroacupuncture at the Zusanli point on upper gastrointestinal motility in rabbits

JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 10 2007
Wei-Xin Niu
Abstract Background and Aim:, The purposes of this study were to investigate the regulative effect of acupuncture on gastrointestinal motility in rabbits and to explore the probable mechanism of electroacupuncture. Methods:, The experiment was performed on 30 rabbits implanted with three pairs of electrodes, which were equally divided into three groups: the control group, the Zusanli group, and the non-acupuncture point group. The gastrointestinal myoelectrical activity of each conscious rabbit was recorded when acupuncture was applied. Motilin in plasma, cholecystokinin (CCK) in serum, the activity of acetylcholine esterase, nitric oxide synthase (NOS), and the vesicle of nerve endings in the stomach tissue and jejunum were investigated. Results:, It was found that electroacupuncture did not exert much influence on the slow wave of gastrointestinal myoelectrical activity, but significantly increased the number and amplitude of spikes. In the Zusanli group, the concentration of motilin and CCK was much higher at the post-acupuncture stage than at the pre-acupuncture stage. Electroacupuncture significantly enhanced the activity of acetylcholine esterase. Moreover, we found out that in the Zusanli group, the number of vesicles without granula was significantly fewer than in the control group. The activity of NOS was less in the Zusanli group than in the control group. Conclusions:, Acupuncture may enhance the gastrointestinal myoelectrical activity of conscious rabbits. The cholinergic nerve, nitric oxide, motilin, and CCK may contribute to acupuncture mechanisms. [source]

Double-blind, randomized, placebo-controlled study to evaluate the effects of tegaserod on gastric motor, sensory and myoelectric function in healthy volunteers

ALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 5 2006
N. J. TALLEY
Summary Background The effects of tegaserod on gastric accommodation and postprandial satiety remain unclear. Aim To compare the effects of tegaserod 6 mg twice daily vs. placebo on gastric volumes, postprandial symptoms, gastric emptying, small bowel transit and the surface electrogastrogram in female and male healthy volunteers. Methods Randomized, double-blind, placebo-controlled study evaluated gastric function before and after 7 days of tegaserod 6 mg twice daily (n = 21) vs. placebo (n = 20) in healthy volunteers. Validated methods were used to study gastric emptying, myoelectrical activity, volumes and satiation postnutrient challenge. Results There were no significant effects of tegaserod on the primary endpoints assessing gastric function: emptying of solids or liquids, total gastric volumes or myoelectrical activity. Maximum tolerated volume and aggregate symptom score with nutrient challenge on placebo were 1035 mL (±44) and 130 (±15) vs. 989 mL (±43) and 117 (±15) during tegaserod, respectively (all P = N.S.). Postprandial change in proximal gastric volume by single photon emission-computed tomography was decreased in females on tegaserod (246 ± 30) vs. placebo (358 ± 32) (P = 0.015). Proximal fasting volumes in females were increased on tegaserod (126 ± 12) vs. placebo (92 ± 13) (P = 0.066). Conclusions While tegaserod decreased proximal gastric volume change after a meal, it does not appear to have significant effects on gastric motor and sensory function in healthy individuals. Further studies are required in patients with disturbances of gastric motor and sensory function. [source]

22 Comparison of multichannel electrogastrograms obtained with the use of three different electrode types

NEUROGASTROENTEROLOGY & MOTILITY, Issue 6 2006
K JONDERKO
Background/Aims:, Multichannel recording of the gastric myoelectrical activity (GMA) is a promising evolution of electrogastrography. In the study we searched for electrodes the most suitable to obtain high quality multi-channel electrogastrograms. Methods:, Twelve young volunteers (9 F, 3 M, aged 24.3 ± 0.6 years) underwent on separate days three four-channel electrogastrographic recordings of the GMA: 30 min fasted and 90 min after a solid meal stimulation. The electrogastrograms were recorded in randomized order with 3M Red Dot class Ag/AgCl electrodes designed primarily for long-term electrocardiographic monitoring: type2222 (conductive area, CA/total area, TA): 2.00/10.24 cm2, type2271 2.54/29.64 cm2, type2660 11.64/11.64 cm2 (total surface conductive!) and subsequently analysed with Polygram NetÔ EGG 311224 software (Medtronic, USA). Electrical resistance between active electrodes relative to the reference one was measured with a digital ohmmeter before and after the recording session. Results:, Type2660 yielded consistently higher electrical resistance than the other electrode types, moreover in the case of type2271 and type2660 electrical conductivity significantly improved at the end of the recording relative to the basal measurement. Analysis of variance involving the relative time-share of normogastria, meal-induced change in dominant power, as well as a set of parameters unique for the multichannel electrogastrography and intended to characterize the so-called spatial displacement of the gastric slow waves did not reveal any statistically significant effect of the electrode type on the parameters of the multichannel electrogastrogram. Although, when particular numerical data were inspected, type2271 was found to perform slightly worse than the other electrode types. Type2271 was also rated the less handy among the electrodes tested. Conclusion:, Multichannel surface electrogastrography seems to be technically feasible with any type of high quality Ag/AgCl electrodes available on the market, whereas small dimensions enabling easy placement on the abdomen may be a feature favouring the choice of a particular electrode type for this examination. [source]

34 Senso-reflexory control of the gastric myoelectrical activity , effect of oral exposure to a sweet or a bitter taste on a multichannel electrogastrogram

NEUROGASTROENTEROLOGY & MOTILITY, Issue 6 2006
M DZIELICKI
Aim:, To examine the effect of sensory stimulation with a sweet or a bitter taste on the interdigestive gastric myoelectrical activity (GMA) in humans. Methods:, Eighteen healthy subjects (10F, 8M) underwent on two separate days four-channel electrogastrographic recordings comprising three consecutive 35 min periods: (i) basal fasted, (ii) a stimulation epoch while a subject was chewing an agar cube soaked with a taste-delivering substance (saccharose for the sweet taste, quinine hydrochloride for the bitter taste), (iii) a post-stimulatory (recovery) epoch. An electrocardiogram was simultaneously registered for the purpose of the heart rate variability (HRV) analysis. Results:, Exposure to the sweet taste brought about an increase in the power of the high frequency (HF: 0.15,0.4 Hz) band of the power spectrum-analyzed HRV data. The bitter taste had no effect on the HRV. During the stimulation and the recovery epoch a statistically significant augmentation in the relative time share of tachy- and bradygastria within the multichannel electrogastrogram was found either with the sweet or the bitter taste. Whereas no any other modifications of the GMA were elicited by the sweet taste, the exposure to the bitter taste resulted in a statistically significant decrease in the relative time share of normogastria, a decline in the dominant frequency and the dominant power of the gastric slow waves, as well as a reduction in the percentage of the slow wave coupling. Conclusions:, (i) Exposure to the sweet taste elicits a vagal arousal expressed by an increase in the HF power, whereas the bitter taste does not affect the equilibrium between the parasympathetic and the sympathetic component of the autonomous nervous system; (ii) The increased relative time contribution of tachy- and bradygastria within the electrogastrogram during both the stimulation and the recovery epoch should be considered an unspecific phenomenon because it accompanied stimulation either with the sweet or the bitter taste; (iii) The inhibitory effect of the bitter taste on the GMA, reflected by a diminution in the dominant frequency and the dominant power of the gastric slow waves, as well as their reduced coupling, may be indicative of an evolutionary archetype of a warning reaction of the human (mammalian) organism towards this taste. [source]

Oxyntomodulin and glicentin are potent inhibitors of the fed motility pattern in small intestine

NEUROGASTROENTEROLOGY & MOTILITY, Issue 4 2004
S. Pellissier
Abstract, Glicentin (GLIC) and oxyntomodulin (OXM or GLIC 33-69) are gut hormones which regulate digestion. They are known to reduce digestive secretions and to delay gastric emptying. Their biological activities on intestinal motility are still unknown. The effect of a systemic GLIC or OXM increase was investigated in rats on the food intake, the postprandial myoelectrical activity of small intestine and the orocaecal transit. An OXM or GLIC i.v. infusion was applied during the 5 min preceding food onset and during the first 15 min of food intake. This determined a three- to fourfold increase of the preprandial OXM,GLIC level. The OXM or GLIC plasma increase did not modify food intake. OXM infusion slowed down gastric emptying when the stomach contained 3/4 of the ingested food (before T 3 h). The quantity of food delivered in jejunum was subsequently smaller (P < 0.05). In the small intestine, the duration of postprandial myoelectrical activity (50,60 min g,1 of ingested food) was reduced by 70% (P < 0.001) on duodenum or jejunum and by 54% (P < 0.01) on ileum in OXM-treated rats. An interdigestive motility profile was settled and an acceleration of both gastric emptying and transit rate was thereafter evidenced (after T 3 h). GLIC also reduced the duration of the postprandial myoelectrical activity on duodenum and jejunum (65 and 63% respectively, P < 0.05), but was not as efficient as OXM on ileum. In pathological states such as acute adult gastroenteritis, OXM and GLIC exhibit a two- to fivefold increase in their plasma concentrations. The present findings suggest that OXM and GLIC could, in that disease, contribute to exclude pathogens, due to their joined action on gut motility. [source]

Electrogastrography: a document prepared by the gastric section of the American Motility Society Clinical GI Motility Testing Task Force

NEUROGASTROENTEROLOGY & MOTILITY, Issue 2 2003
H. P. Parkman
Abstract The objective of this document is to present the consensus opinion of the American Motility Society Clinical GI Motility Testing Task Force on the performance and clinical utility of electrogastrography (EGG). EGG is a non-invasive means of recording human gastric myoelectrical activity or slow waves from cutaneous leads placed over the stomach. In healthy volunteers, EGG tracings exhibit sinusoidal waveforms with a predominant frequency of 3 cycles per minute (cpm). Clinical studies have shown good correlation of these cutaneous recordings with those acquired from serosally implanted electrodes. The amplitude of the EGG waveform increases with ingestion of caloric or non-caloric meals. Some patients with nausea, vomiting, or other dyspeptic symptoms exhibit EGG rhythm disturbances or blunting of meal-evoked EGG signal amplitude increases. These abnormalities correlate to some degree with delayed gastric emptying of solids. In selected patients, EGG may be complementary to gastric emptying testing. To date, no therapies have convincingly demonstrated in controlled studies that correcting abnormalities detected by EGG improves upper gastrointestinal symptoms. Proposed clinical indications for performance of EGG in patients with unexplained nausea, vomiting and dyspeptic symptoms must be validated by prospective controlled investigations. [source]

Alterations of intestinal motor responses to various stimuli after Nippostrongylus brasiliensis infection in rats: role of mast cells

NEUROGASTROENTEROLOGY & MOTILITY, Issue 3 2000
J. Gay
Nippostrongylus brasiliensis infection induces jejunal mastocytosis associated with enteric nerve remodelling in rats. The aim of this study was to evaluate the intestinal motility responses to meals and to neurotransmitters involved in the control of gut motility (acetylcholine (carbachol), substance P and neurokinin A) in both control and N. brasiliensis -infected rats 30 days post-infection. All rats were equipped with NiCr electrodes in the jejunum to record myoelectrical activity. The duration of disruption of the jejunal migrating myoelectrical complexes (MMC) induced by the different stimuli was determined. Meal ingestion and substance P administration disrupted the MMC pattern for similar durations in the two groups. Carbachol and neurokinin A induced a significantly longer MMC disruption in post-infected rats than in controls (125 ± 8.3 vs. 70 ± 6 min for carbachol 100 ,g kg,1 and 51 ± 4 vs. 40 ± 2 for neurokinin A 50 ,g kg,1). The enhanced motor response in postinfected rats was reduced by previous mast cell stabilization with ketotifen or mast cell degranulation with compound BrX 537 A. In conclusion, the increased intestinal motor reactivity to carbachol and neurokinin A in post- N. brasiliensis -infected rats depends upon intestinal mast cell hyperplasia and degranulation. [source]

The Chinese herbal preparation Qing Yi Tang (QYT) improves intestinal myoelectrical activity and Increases intestinal transit during acute pancreatitis in Rodents

Electrogastrography in children and adolescents with type 1 diabetes: Weak correlation with metabolic control parameters

ACTA PAEDIATRICA, Issue 11 2006
Ewa Toporowska-Kowalska
Abstract Aim: To evaluate gastric myoelectrical activity with respect to duration and metabolic control of type 1 diabetes mellitus (T1DM). Methods: 172 children and adolescents with T1DM (mean 14.4±3.7 y), divided into subgroups depending on diabetes duration (<5 and > 5 y), and 35 healthy controls (mean 13.93±3.59 y) were examined. All subjects underwent electrogastrography (EGG) performed after overnight fasting. In subjects with T1DM, haemoglobin A1c (HbA1c) and blood glucose levels during EGG records were measured. Results: 15.69% of T1DM patients and 91.42% of the controls fulfilled normal EGG criteria (p < 0.001). T1DM subjects had a lower percentage of fasting normogastria (34.56±27.35% vs 69.84±18.16%, p = 0.0001) and higher bradygastria (51.97±30.24% vs 19.11±15.01%, p = 0.0001) compared to controls. In diabetic patients, an increase in postprandial normogastria (60.37±23.96% vs 76.68±12.38, p < 0.05) and a decrease in bradygastria percentage (25.67±21.01% vs 9.58±7.13%, p < 0.05) was observed. In children with disease < 5 y, diabetes duration correlated with power ratio (r= - 0.27, p = 0.01), postprandial normogastria (r= - 0.24, p = 0.03) and tachygastria (r= 0.25, p = 0.02). Weak correlations between EGG parameters and glucose (preprandial dominant frequency r= - 0.19, p < 0.05; postprandial normogastria r= 0.23, p < 0.01) and HbA1c levels (preprandial bradygastria r= 0.19, postprandial dominant power r= 0.23; p < 0.05) were observed. Conclusion: Gastric myoelectrical rhythm derangement is present in a large proportion of young diabetic patients. Bradygastria is the most prominent EGG abnormality. Weak correlation was found between EGG parameters and diabetes metabolic control. [source]