Intestinal Myoelectric Activity Research Articles

Pharmacological Correction of Gastrointestinal Motility in Patients with Functional Gastrointestinal Disorders

Actuality. Functional gastrointestinal disorders (FGID) represent a significant public public health issue. The foundation of effective therapy for FGID with overlap syndrome - functional dyspepsia (FD, epigastric pain syndrome) with gastric hypersecretion and irritable bowel syndrome (IBS)-is considered to be pathogenetic therapy or the combined use of symptomatic medications. Aim. Assessment of the impact of pathophysiological therapy with the drug Kolofort and symptomatic treatments, including proton pump inhibitors (PPIs) and the myotropic antispasmodic mebeverine hydrochloride in prolonged-release capsules, on the clinical manifestations of FGIDs with overlap syndrome - FD (pain syndrome in the epigastric region) with gastric hypersecretion and IBS - includes evaluating effects on myoelectric activity of the gastrointestinal tract. Design. (conception) An open cohort-controlled comparative study on the effects of Kolofort, omeprazole, rabeprazole, and mebeverine hydrochloride in prolonged-release capsules on intestinal motility in patients with FGID and overlap syndrome - functional dyspepsia (FD, epigastric pain syndrome) with gastric hypersecretion and IBS. Materials and Methods. A total of 107 patients suffering from FGID with overlap syndrome - functional dyspepsia (FD, epigastric pain syndrome) with gastric hypersecretion and IBS - were examined. Results. A one-month course of Kolofort significantly improved the psychological status of IBS patients and enhanced intestinal myoelectric activity. Since there is no available literature on Kolofort’s effect on gastric secretion levels, PPIs and mebeverine hydrochloride were used in the treatment of patients with FGID - FD (epigastric pain syndrome) with gastric hypersecretion and IBS overlap syndrome. The use of PPIs, such as omeprazole and rabeprazole, in these patients eliminated gastric hypersecretion and abdominal pain. Rabeprazole demonstrated faster effects than omeprazole and also normalized gastrointestinal motility more efficiently. For patients with FGIDs - FD with gastric hypersecretion and overlap syndrome with IBS, a combined therapy of omeprazole and the myotropic antispasmodic mebeverine hydrochloride in prolonged-release capsules is recommended. This combination, within two weeks, resolved clinical symptoms in 97% of cases, improved the quality of life, and normalized intestinal motility and gastrointestinal myoelectric activity. However, monotherapy with rabeprazole at a daily dose of 20 mg more rapidly addressed symptoms of gastric hypersecretion and and normalized gastrointestinal motility.

A novel pilot study to evaluate the efficacy and safety of a wireless patch system in patients with chronic nausea and vomiting.

Gastric sensorimotor disorders (functional dyspepsia [FD] and gastroparesis [GP]) are prevalent and burdensome. Prolonged ambulatory recording using a wireless patch may provide novel information in these patients. Consecutive adult patients (age ≥ 18 years) referred for gastric emptying scintigraphy (GES) were eligible for study inclusion. Patients were excluded if they had prior foregut surgery; were taking opioids or other medications known to affect gastric emptying; had a HgbA1C > 10; or were recently hospitalized. Three wireless motility patches were applied to the skin prior to GES. Patients wore the patches for 6 days while recording meals, symptoms, and bowel movements using an iPhone app. Twenty-three consecutive adults (87% women; mean age = 43.9 years; mean BMI = 26.7 kg/m2) were enrolled. A gastric histogram revealed three levels of gastric myoelectric activity: weak, moderate, and strong. Patients with delayed gastric emptying at 4 h had weak gastric myoelectrical activity. Patients with nausea and vomiting had strong intestinal activity. Those with FD had weak gastric and intestinal myoelectric activity, and a weak meal response in the stomach, intestine, and colon compared to those with nausea alone or vomiting alone. Patients with FD, and those with delayed gastric emptying, had unique gastrointestinal myoelectrical activity patterns. Reduced postprandial pan-intestinal myoelectric activity may explain the symptoms of FD in some patients. Recording gastrointestinal activity over a prolonged period in the outpatient setting has the potential to identify unique pathophysiologic patterns and meal-related activity that distinguishes patients with distinct gastric sensorimotor disease states.

Potential value of gastrointestinal myoelectrical activity in the diagnosis of anxiety-depression disorder: a population-based study

BackgroundDepression and anxiety are frequently coexisted mental illness. The lack of solid objective diagnostic criteria has led to a high rate of suicide. The brain-gut axis bridges the gastrointestinal system with neuropsychiatric disorders. However, it is still not possible to reflect mental disease with gastrointestinal information. The study aimed to explore the auxiliary diagnostic value of gastrointestinal myoelectrical activity in anxiety-depression disorders (ADD) without gastrointestinal disturbance.MethodsA natural population cohort from 3 districts in Western China were established. The Patient Health Questionnaire-9 and the Generalized Anxiety Disorder-7 were used to assess ADD. Gastrointestinal myoelectrical activity of ADD were measured by multi-channel cutaneous electrogastroenterogram (EGEG). Then the parameters of EGEG between ADD and healthy controls were analyzed.ResultsThe average amplitude and response area of intestinal channel in ADD were significantly lower than those of controls (153.49 ± 78.69 vs. 179.83 ± 103.90, 57.27 ± 29.05 vs. 67.70 ± 38.32), which were shown to be protective factors for ADD (OR = 0.944 and 0.844, respectively). Further, the scale item scores related to the core symptoms of anxiety and depression were also associated with these two channels (p < 0.05), and the gastrointestinal electrical signals of ADD are significantly changed in the elderly compared to the young adults.ConclusionsThe intestinal myoelectrical activity has a certain auxiliary diagnostic value in psychiatric disorders and is expected to provide objective reference for the diagnosis of anxiety and depression.

THU264 Enteric Activity Enhanced Ileal GLP-1 Secretion

Abstract Disclosure: Y. Chen: None. G. Jiao: None. Y. Lei: None. Y. Li: None. L. Sha: None. GLP-1 is a multifunctional endocrine hormone secreted by intestinal L cells in gastrointestinal tract contributing to the maintenance of glucose homeostasis. The distal part of small intestine such as ileum has a great density of L cells. In this study, we provided a direct evidence that enteric activity modulated GLP-1 secretion in rat ileum. Methods: A segment of rat ileum was dissected. The proximal section of the ileum segment was used to pace the enteric activity with an intestinal electrical stimulation(IES) designed from our previous intestinal myoelectric activity analyzing mimicking the ileum activity in feeding and the adjacent distal section was perfused vascularly to collect and measure GLP-1 secretion. Ileal motility in the distal section of the ileum segment was also recorded to monitor the enteric activity. The lumen of the ileum segment was filled with saline. Results: The frequency and the amplitude of spontaneous contraction in the distal ileum section was 14.14±2.82 cycles/min and 1.58±0.46 g (n=5). The area under curve (AUC) was 180.40±61.68 g·s. The GLP-1 secretion level in the distal ileum section was 15.47±0.46 pg/mL. With IES, The frequency was increased to 18.27±2.23 cycles/min (P&amp;lt;0.05, n = 5) and the AUC was increased to 303.64±79.75 (p&amp;lt;0.05). The amplitude had no significant change (P&amp;gt;0.05). The GLP-1 secretion was significantly increased to 24.71±2.47 pg/mL(p&amp;lt;0.05) with enhanced enteric activity. we provided a direct evidence to show the enhancement of GLP-1 secretion with enteric activity. Our result indicated that with feeding-simulated enteric activity, GLP-1 secretion could be elevated by around 60 percent in rat ileum. (supported by the National Natural Science Foundation of China, Grant No.81670492) Presentation: Thursday, June 15, 2023

An efficient online peak detection algorithm for synchronized intestinal electrical stimulation and its application for treating diabetes.

Obesity is one of leading risk factors for type 2 diabetes and other types of chronic diseases. Synchronized intestinal electrical stimulation (SIES) has been explored for treating obesity and diabetes. In SIES, electrical stimulation is delivered to the small intestine in synchronization with the intrinsic intestinal myoelectrical activity (its basic rhythm is called slow wave) and therefore, the accurate detection of intestinal slow waves is critically important for SIES. The aim of this study is to detect the peaks in intestinal slow waves in real-time based on the automatic multiscale peak detection (AMPD) method. In this paper, we introduce an efficient technique for real-time detection of peaks in intestinal slow waves. The presented method is based on peak estimation of a given quasi-periodic signal using the AMPD method. This method uses a multi-scale approach to identify the peaks of the intestinal slow waves with high detection accuracy and a minimal delay. Throughout the experiments, the multi-scale technique is used to estimate the quasi-periodic signals using different signal-to-noise ratio, λ (optimal scale), and the "lag" β (number of datapoints for right hand estimation) as important performance factors. The performance of the presented method is also calculated and utilized in the comparison process for 10 datasets of the intestinal slow waves from rats at λ = 150ms and two values of β = 100ms and 150ms. The experimental results show that the presented method has good overall accuracy for online peak detection while maintaining low memory and computational complexity. Numerically, the overall accuracy is above 90%, and 98% for the rodent intestinal slow waves at a time-lag of 150ms. The developed SIES system has been applied to successfully reduce postprandial blood glucose in a rodent model of hyperglycemia. In conclusion, the developed algorithm is adequate for on-line peak detection of the intestinal slow waves; the SIES method used the developed peak detection algorithm which is effective in reducing postprandial blood glucose in a rodent model of hyperglycemia.

Plasma atropine concentrations associated with decreased intestinal motility in horses.

IntroductionAtropine is an essential part of the treatment protocol for equine uveitis. Topical atropine administration has been associated with decreased intestinal motility and abdominal pain in horses. Experimental studies have indicated that frequent dosing is associated with a higher risk than dosing every 6 h. Unfortunately, no quantitative pharmacodynamic data for inhibition of the equine gut are published.Materials and methodsEight standardbred horses were assigned to receive either atropine or saline (control) to be infused over 30 min in a two-treatment cross-over design. Atropine concentrations in plasma were measured using ultra-high-performance liquid chromatography–tandem mass spectrometry. Intestinal motility was measured using borborygmi frequency and electrointestinography (EIG). Experimental data were analyzed using a non-linear mixed effects model. The model was then used to simulate different dosing regimens.ResultsAtropine significantly decreased borborygmi response and EIG response. Six horses developed clinical signs of abdominal pain. The pharmacokinetic typical values were 0.31, 1.38, 0.69, and 1.95 L/kg·h for the volumes of the central, the highly perfused, the scarcely perfused compartments, and the total body clearance, respectively. The pharmacodynamic typical values were 0.31 μg/L and 0.6 and 207 nV27 cpm for the plasma concentration at 50% of the maximum response and the maximum response and the baseline of cecal EIG response, respectively. Six different dosing regimens of topical atropine sulfate to the eye (0.4 and 1 mg every hour, every 3 h, and every 6 h) were simulated.ConclusionThe IV PK/PD data coupled with simulations predict that administration of 1 mg of topical atropine sulfate administered to the eye every hour or every 3 h will lead to atropine accumulation in plasma and decreased intestinal myoelectric activity. Administration every 6 h predicted a safe dosing regimen in full-sized horses. Clinical studies would be valuable to confirm the conclusions. For smaller equids and horses put at risk for colic due to othercauses, droplet bottles that deliver 40 μl of 1% atropine sulfate per drop or less may be used to lower the risk further.

The Mysterious Island: Insula and Its Dual Function in Sleep and Wakefulness.

In the recent sleep studies, it was shown that afferentation of many cortical areas switches during sleep to the interoceptive one. However, it was unclear whether the insular cortex, which is often considered as the main cortical visceral representation, maintains the same effective connectivity in both states of vigilance, or processes interoceptive information predominantly in one state. We investigated neuronal responses of the cat insular cortex to electrical stimulations of the intestinal wall delivered during wakefulness and natural sleep. Marked increase was observed in the number of insular neurons responding to this stimulation in sleep comparing to wakefulness, and enlarged amplitudes of evoked local field potentials were found as well. Moreover, most of the cells responding to intestinal stimulation in wakefulness never responded to identical stimuli during sleep and vice versa. It was also shown that applied low intensity intestinal stimulations had never compromised sleep quality. In addition, experiments with microstimulation of the insular cortex and recording of intestinal myoelectric activity demonstrated that effective insula-to-gut propagation also happened only during sleep. On the other hand, the same insular stimulations in wakefulness led to contractions of orofacial muscles. The evoked face movements gradually disappeared in the course of sleep development. These findings demonstrate that pattern of efficient afferent and efferent connections of the insular cortex changes with transition from wakefulness to sleep.

Can ocular administration of atropine cause colic?

Can ocular administration of atropine cause colic?

Uncut Roux-en-Y reconstruction after totally laparoscopic distal gastrectomy with D2 lymph node dissection for early stage gastric cancer.

Roux Stasis Syndrome is a well-known complication after Roux-en-Y reconstruction. Uncut Roux-en-Y technique, would preserve unidirectional intestinal myoelectrical activity and diminish Roux Stasis Syndrome. A 61 years old woman with moderately differentiated adenocarcinoma of antrum who was diagnosed by gastroscopy and histological test, underwent totally laparoscopic distal gastrectomy (TLDG) with D2 lymph node dissection and uncut Roux-en-Y reconstruction (URYR). The length of operation was 190 min with bleeding of about 40 mL. The patient recovers well postoperation and discharged from hospital on the 7th day. TLDG with intracorporeal uncut Roux-en-Y gastrojejunostomies using laparoscopic linear staplers was safe and feasible with minimal invasiveness.

Prony’s method implementation for slow wave identification of electroenterogram signals

El objetivo del presente trabajo es identifi car la onda lenta (OL) de la actividad bioelectrica del intestino delgado registrada en la superfi cie abdominal (electroenterograma), para detectar que registro interno se detecta en la superfi cie abdominal. En este estudio se utilizo el metodo de Prony. Los registros internos y externos fueron adquiridos de manera simultanea de cinco perros Beagle (de 10 sesiones de registro). El Criterio de Informacion de Akaike (CIA) fue utilizado para la obtencion de los ordenes optimos del metodo de Prony, y se aplico a cada minuto de longitud de senal mioelectrica tanto abdominal como interna. El orden optimo encontrado fue de p = 29 y q = 1, con una resolucion de frecuencia ∆f = 0.06 Hz. La frecuencia de los picos maximos de la senal del espectro se encontro en torno a 0.3 Hz. El Analisis del metodo de Prony muestra que la OL puede detectarse en los registros abdominales de la actividad mioelectrica intestinal sin interferencias respiratorias y estadisticamente puede determinarse el registro interno que se corresponde con el registro en la superfi cie abdominal.

Neuropeptide S inhibits gastrointestinal motility and increases mucosal permeability through nitric oxide.

Neuropeptide S (NPS) receptor (NPSR1) polymorphisms are associated with enteral dysmotility and inflammatory bowel disease (IBD). This study investigated the role of NPS in conjunction with nitrergic mechanisms in the regulation of intestinal motility and mucosal permeability. In rats, small intestinal myoelectric activity and luminal pressure changes in small intestine and colon, along with duodenal permeability, were studied. In human intestine, NPS and NPSR1 were localized by immunostaining. Pre- and postprandial plasma NPS was measured by ELISA in healthy and active IBD humans. Effects and mechanisms of NPS were studied in human intestinal muscle strips. In rats, NPS 100-4,000 pmol·kg(-1)·min(-1) had effects on the small intestine and colon. Low doses of NPS increased myoelectric spiking (P < 0.05). Higher doses reduced spiking and prolonged the cycle length of the migrating myoelectric complex, reduced intraluminal pressures (P < 0.05-0.01), and increased permeability (P < 0.01) through NO-dependent mechanisms. In human intestine, NPS localized at myenteric nerve cell bodies and fibers. NPSR1 was confined to nerve cell bodies. Circulating NPS in humans was tenfold below the ∼0.3 nmol/l dissociation constant (Kd) of NPSR1, with no difference between healthy and IBD subjects. In human intestinal muscle strips precontracted by bethanechol, NPS 1-1,000 nmol/l induced NO-dependent muscle relaxation (P < 0.05) that was sensitive also to tetrodotoxin (P < 0.01). In conclusion, NPS inhibits motility and increases permeability in neurocrine fashion acting through NO in the myenteric plexus in rats and humans. Aberrant signaling and upregulation of NPSR1 could potentially exacerbate dysmotility and hyperpermeability by local mechanisms in gastrointestinal functional and inflammatory reactions.

The impact of inflammatory cells in malignant ascites on small intestinal ICCs' morphology and function.

Malignant ascites is one of the common complication at the late stage of abdominal cancers, which may deteriorate the environment of abdominal cavity and lead to potential damage of functional cells. Interstitial cells of Cajal (ICCs) are mesoderm-derived mesenchymal cells that function normal gastrointestinal motility. The pathological changes of ICCs or the reduced number may lead to the motility disorders of gastrointestinal tract. In this study, through analysis of malignant ascites which were obtained from cancer patients, we found that inflammatory cells, including tumour-infiltrating lymphocytes, accounted for 17.26 ± 1.31% and tumour-associated macrophages, occupied 19.06 ± 2.27% of total cells in the ascites, suggesting these inflammatory cells, in addition to tumour cells, may exert important influence on the tumour environment of abdominal cavity. We further demonstrated that the number of mice ICCs were significant decreased, as well as morphological and functional damage when ICCs were in the simulated tumour microenvironment in vitro. Additionally, we illustrated intestinal myoelectrical activity reduced and irregular with morphological changes of ICCs using the mice model of malignant ascites. In conclusion, our data suggested that inflammatory cells in malignant ascites may damage ICCs of the small intestine and lead to intestinal motility disorders.

Hyperglycemia-induced small intestinal dysrhythmias attributed to sympathovagal imbalance in normal and diabetic rats.

Hyperglycemia is known to induce dysrhythmias in the stomach; however, it is unknown whether they are also induced in the small intestine. Autonomic dysfunction is commonly noted in diabetes but the role it plays in hyperglycemia-induced dysrhythmias remains unknown. This study aimed to explore the effects of hyperglycemia on intestinal myoelectrical activity and the role of autonomic functions in hyperglycemia. Small intestinal myoelectrical activity (slow wave and spike activity) and autonomic functions (assessed by the spectral analysis of heart rate variability) were measured in Goto-Kakizaki diabetic rats and control rats treated with acute glucagon. Blood glucose was measured and its correlation with intestinal slow waves was determined. (1) The diabetic rats showed reduced regularity in intestinal slow waves in fasting and fed states (p < 0.001 for both), and increased sympathovagal balance (p < 0.05) in comparison with the control rats. The regularity in intestinal slow waves was negatively correlated with the HbA1c level in all rats (r = -0.663, p = 0.000). (2) Glucagon injection in the control rats induced transient hyperglycemia, intestinal slow wave dysrhythmias and impaired autonomic functions, similar to those observed in the diabetic rats. The increase in blood glucose was correlated with the decrease in the regularity of intestinal slow waves (r = -0.739, p = 0.015). Both spontaneous and glucagon-induced hyperglycemia results in slow wave dysrhythmias in the small intestine. Impairment in autonomic functions (increased sympathovagal balance) may play a role in hyperglycemia-induced dysrhythmias.

Therapeutic effect and mechanism of electroacupuncture at Zusanli on plasticity of interstitial cells of Cajal: a study of rat ileum.

BackgroundElectroacupuncture (EA) is one of the techniques of acupuncture and is believed to be an effective alternative and complementary treatment in many disorders. The aims of this study were to investigate the effects and mechanisms of EA at acupoint Zusanli (ST36) on the plasticity of interstitial cells of Cajal (ICCs) in partial bowel obstruction.MethodsA Sprague Dawley rat model of partial bowel obstruction was established and EA was conducted at Zusanli (ST36) and Yinglingquan (SP9) in test and control groups, respectively. Experiments were performed to study the effects and mechanisms of EA at Zusanli on intestinal myoelectric activity, distribution and alteration of ICCs, expression of inflammatory mediators, and c-Kit expression.Results1) EA at Zusanli somewhat improved slow wave amplitude and frequency in the partial obstruction rats. 2) EA at Zusanli significantly stimulated the recovery of ICC networks and numbers. 3) the pro-inflammatory mediator TNF-α and NO activity were significantly reduced after EA at Zusanli, However, no significant changes were observed in the anti-inflammatory mediator IL-10 activity. 4) EA at Zusanli re-expressed c-Kit protein. However, EA at the control acupoint, SP9, significantly improved slow wave frequency and amplitude, but had no effect on ICC or inflammatory mediators.ConclusionsWe concluded that EA at Zusanli might have a therapeutic effect on ICC plasticity, and that this effect might be mediated via a decrease in pro-inflammatory mediators and through the c-Kit signaling pathway, but that the relationship between EA at different acupoints and myoelectric activity needs further study.

An experimental infectious diarrhoea model to assess intestinal myoelectrical activity

Introduction: Diseases causing infectious diarrhoea, such as cholera, are a leading cause of childhood death and adult morbidity. At the level of enterocytes, cholera toxin (CT) – produced by Vibrio cholerae – induces a dramatic increase in electrolyte and water secretion by increasing intracellular cAMP and also by stimulating enteric nervous components. CT can modulate intestinal myoelectrical activity but its exact nature is not understood. One method used to assess this is high-resolution spatiotemporal electrical mapping. Aims and objectives: The study aimed to develop an animal model of cholera to assess myoelectrical activity in the gastrointestinal system. Materials and methods: Four young adult black mice were anaesthetized using pentobarbital (pentobarbitone) (pentobarbital sodium salt; Sigma-Aldrich) and jejunal loops were constructed. A total of 2μg of CT was instilled into the jejunal loops and incubated for 5 hours, after which the jejunal fluid was measured and jejunal sheets were used for slow-wave electrical recording for frequency, amplitude and velocity by fixing them in an organ bath using 121 mini electrodes. Results: CT-incubated animal jejuna showed significant fluid secretion after a period of 5 hours compared with the control group (CT group 1000μl vs. control group 100μl; P>0.001). The CT group showed an increase in slow-wave velocity compared with the controls and there was no change in frequency or amplitude. These are preliminary results and require further experimentation to confirm the significance. Conclusion: We have successfully developed an infectious model of diarrhoea, which can be utilized for myoelectrical recordings and analysis. Acknowledgements: We would like to acknowledge Dr Sandeep Subramanya, Dr Wim Lammers and Ms Betty Stephen, who helped us through this project.

Enhancement of Non-Invasive Recording of Electroenterogram by Means of a Flexible Array of Concentric Ring Electrodes

Monitoring intestinal myoelectrical activity by electroenterogram (EEnG) would be of great clinical interest for diagnosing gastrointestinal pathologies and disorders. However, surface EEnG recordings are of very low amplitude and can be severely affected by baseline drifts and respiratory and electrocardiographic (ECG) interference. In this work, a flexible array of concentric ring electrodes was developed and tested to determine whether it can provide surface EEnG signals of better quality than bipolar recordings from conventional disc electrodes. With this aim, sixteen healthy subjects in a fasting state (>8 h) underwent recording. The capability of detecting intestinal pacemaker activity (slow wave) and the influence of physiological interferences were studied. The signals obtained from the concentric ring electrodes proved to be more robust to ECG and respiratory interference than those from conventional disc electrodes. The results also show that intestinal EEnG components such as the slow wave can be more easily identified by the proposed system based on a flexible array of concentric ring electrodes. The developed active electrode array could be a very valuable tool for non-invasive diagnosis of disease states such as ischemia and motility disorders of the small bowel which are known to alter the normal enteric slow wave activity.

Gastrointestinal effects of diazepam-withdrawal are linked to activation of central cholecystokinin-ergic pathways in rats.

The influence of flumazenil-precipitated diazepam withdrawal on intestinal myoelectric activity and colonic transit was evaluated, in diazepam-dependent rats. Administered intraperitoneally, flumazenil (15 mg kg-1) induced a strong stimulation of the duodenal spiking activity lasting 197 +/- 20 min, and accelerated colonic transit corresponding to a significantly (P < 0.05) increased value of the geometric centre (3.52 +/- 0.23 vs 2.44 +/- 0.1 for the control). Both devazepide and L365260 administered intracerebroventricularly at a dose of 10 micrograms kg-1 abolished the flumazenil-induced withdrawal effect on the duodenum, whereas at a lower dose (1 microgram kg-1) only L365260 was able to antagonize this effect. In the same way, devazepide, loxiglumide and L365260 suppressed the effect of precipitated withdrawal on colonic transit when administered intracerebroventricularly at a dose of 10 micrograms kg-1, whereas similar blockade was obtained at a dose of 5 micrograms kg-1 with L365260, and 10 ng kg-1 with PD135-158. It is concluded that in rats precipitated diazepam-withdrawal altered intestinal motility and colonic transit and that these effects are mediated by central release of cholecystokinin (CCK) or activation of CCK-ergic neurons.

Is gastrointestinal dysfunction induced by gastric cancer peritoneal metastasis relevant to impairment of interstitial cells of Cajal?

Although impaired gastrointestinal motility from gastric cancer peritoneal metastasis (GCPM) causes extraordinary pain, its cause is unclear. Interstitial cells of Cajal (ICC) are apparently pacemaker cells, and their loss could cause motor dysfunction. In this study, we developed a mouse model for GCPM, and investigated electrophysiological changes in the small intestine and attendant changes in ICC. We found decreased ICC and disrupted electrical rhythm in the model. Pathologic ICC changes were well described. Cancer peritoneal metastasis may impair intestinal myoelectrical activity by damaging ICC and ICC networks. Interstitial cells of Cajal will be a target of palliative treatment and merit further study.

Effect of muscarinic blocker on enhancing the action of fructus aurantii immaturus on intestinal myoelectric activity in dogs.

To investigate the effect of fructus aurantii immaturus (FAI) on small intestinal electrical activity in dogs. The effect of FAI was observed using a computerized electrophysiological method with the migrating myoelectric complex as a criterion. Fasted, healthy, and conscious dogs were given 100% FAI concentrated solution by gastrostogavage, and as soon as the effect on small intestinal electrical activity appeared, atropine was injected intramuscularly. The enhancing action of FAI was inhibited significantly by atropine, a cholinergic receptor antagonist. Both the number of spike bursts per cluster and the number of spikes per minute in phase II and III and the general cycle were decreased (P < 0.01), although the duration of phase II and the general cycle was prolonged. The effect of FAI might be related to the muscarinic receptors.

Myoelectric activity of the ileum, cecum, proximal loop of the ascending colon, and spiral colon in cows with naturally occurring cecal dilatation-dislocation

To analyze myoelectric activity of the ileum, cecum, proximal loop of the ascending colon (PLAC), and spiral colon in cows with naturally occurring cecal dilatation-dislocation (CDD) and compare findings with those in healthy cows. 8 CDD-affected and 6 healthy control cows. Immediately after diagnosis, CDD-affected cows underwent surgery; control cows underwent a similar surgical procedure. Before completion of surgery, 8 bipolar silver electrodes were implanted in the ileum (n = 2), cecum (1), PLAC (1), and spiral colon (4) of each cow. Beginning the day after surgery, intestinal myoelectric activity was recorded daily (8-hour period) for 4 days; data were analyzed by use of specialized software programs. Quantitative variables of myoelectric activity were compared between groups. Cows of both groups recovered without complications after surgery. In control cows, physiologic myoelectric activity was recorded in all intestinal segments on all days after surgery. Apparently normal myoelectric activity was evident in the ileum of CDD-affected cows on the first day after surgery, but myoelectric activity patterns in the cecum, PLAC, and spiral colon were variable with no organized cyclic myoelectric patterns, incomplete or normally organized migrating myoelectric complexes, and slow normalization over time. After surgery for CDD, normal myoelectric patterns were disrupted in the large intestine of cows, especially in the spiral colon. Clinical recovery with effective transit of ingesta occurred before normalization of myoelectric activity in the large intestine. Therapeutic protocols for restoration or normalization of spiral colon motility should be developed for treatment of CDD-affected cattle.