Electrogastrographic characteristics in patients of stomach cancer

Using a homemade electrogastrography (EGG) system, we studied the characteristics of myoelectrical rhythm in gastric cancer (GC) patients. Based on a short-term Fourier transform, recorded slow waves could be automatically analyzed to obtain the following parameters: dominant frequency/power, percent of normal rhythm (2.4–3.7 cpm), power ratio, etc. Fifty histologically confirmed GC patients (34 men, 16 women) were enrolled before surgical intervention to measure their fasting and postprandial EGG parameters for 30 min. The cancerous parameters of GC patients were then obtained postoperatively. In addition, 46 healthy subjects were enrolled for comparison. When compared to controls, GC patients had the following characteristics: absence of postprandial increase in dominant frequency (GC: 3.04 ± 0.47 vs 3.07 ± 0.44 cpm, NS; controls: 3.02 ± 0.31 vs 3.21 ± 0.25 cpm, P < 0.001), marked power response after meal (P < 0.05), and obvious power ratio (4.58 ± 7.38 vs 2.27 ± 2.05, P < 0.05). Multivariate analysis indicated that advanced GC was the factor responsible for the obvious dominant power enhancement after meal (P < 0.05). Other demographic, clinical, and cancerous factors did not influence EGG parameters. We conclude that apparent arrhythmia is not encountered in GC patients, although they mainly exhibit obvious postprandial power response. Advanced GC is likely responsible for this power enhancement on EGG recording.     

Postprandial water intake inhibits gastric antral motility with increase of cholecystokinin in humans

Objective. The effects of postprandial water intake on the gastrointestinal tract have not been systematically investigated in humans. Material and methods. In 8 healthy volunteers, the gastric antral pressure was measured with a strain gauge transducer, while the esophageal and lower esophageal sphincter pressures were measured with an infused catheter with a Dent sleeve. The esophageal pH at 5 cm above the lower sphincter was measured with a microglass electrode. A standard test meal (560 kcal) was eaten and 500 ml water was ingested 1 h later. The plasma cholecystokinin level was assessed at 4-min intervals. As a control, the same study was done on another day with sham water intake. Results. At 4 min after water intake, there was a significant decrease in gastric antral motility and a significant increase in the plasma cholecystokinin level. Water intake also significantly increased the occurrence of gastroesophageal reflux. Conclusions. The rapid increase in cholecystokinin after water intake may be initiated by a feedback mechanism related to inflow of fatty chyme into the duodenum that inhibits gastric antral activity.     

Effects of trimebutine maleate on gastric motility in patients with gastric ulcer

The effects of trimebutine maleate (TM), a prokinetic drug, on gastrointestinal motility in patients with gastric ulcer were investigated. Twenty patients with active gastric ulcers were allocated to two groups; 10 patients received a proton pump inhibitor alone (PPI group), given orally, and 10 patients received oral TM in combination with a PPI (PPI + TM group), each for a period of 8 weeks. Electrogastrography (EGG) and gastric emptying were measured before and after the treatment period. During the active ulcer stage, tachygastria (more than 0.06 Hz) or bradygastria (less than 0.04 Hz) in the EGG frequency were observed in 9 patients either before or after meals. During the healed ulcer stage, tachygastria or bradygastria was observed in 4 of 10 patients in the PPI group, while in the PPI + TM group, 1 patient had tachygastria and none had bradygastria. Postprandial dip (PD) was observed in 3 of the 20 patients during the active stage, while after treatment, PD was observed in 3 patients in the PPI group and in 6 patients in the PPI + TM group, respectively. Gastric emptying in the PPI group did not show any change between before and after treatment, while that in the PPI + TM group improved significantly after treatment. These results suggest that TM may have an ameliorative effect on abnormal gastric motility in patients with gastric ulcer. (Received Sept. 17, 1997; accepted Apr. 24, 1998)     

Role of sham feeding in postprandial changes of gastric myoelectrical activity

The aim of this study was to evaluate the role of sham feeding in postprandial changes of gastric myoelectrical activity. Eighteen asymptomatic healthy volunteers (10 men, 8 women; mean age: 31), with no history of gastrointestinal disease were studied. Gastric myoelectrical activity was recorded for 30 min at baseline, 30 min after sham feeding, and 1 hr after eating, using surface electrogastrography. The electrogastrogram (EGG) was analyzed by spectral analysis. It was found that the changes of postprandial EGG parameters were significantly correlated with those after sham feeding (EGG dominant power:r=0.6,P<0.01; dominant frequency:r=0.8,P<0.001; percentage of regular slow waves:r=0.7,P<0.003). We concluded that intrinsic gastric electrical activity can be altered by sham feeding and the cephalic phase of digestion plays an important role in the postprandial response of gastric myoelectrical activity.     

肝衰竭大鼠胃动力的改变及其机制的初步探讨

[目的]观察肝衰竭大鼠胃动力的变化并探讨其初步机制。[方法]40只Wistar大鼠随机分为肝衰竭模型组和对照组,采用葡聚糖蓝-2000为标记物观察大鼠胃排空的变化,应用乙酰胆碱酯酶(AchE)和NADPH-d组织化学染色(NOS)及肌间神经丛全层铺片技术,观察肝衰竭大鼠胃窦肌间神经丛胆碱能和氮能神经的变化,免疫组化染色观察胃窦C-kit阳性Cajal间质细胞的变化,并进行定量分析。[结果]与对照组比较,模型组大鼠胃排空明显减弱,胃窦肌间神经丛胆碱能阳性神经元数量减少、神经纤维变细、分布较稀疏,2组比较差异有统计学意义(P<0.01);模型组氮能神经阳性神经元数量及神经纤维分布明显高于对照组(P<0.01);胃窦C-kit阳性Cajal间质细胞明显少于对照组(P<0.01)。[结论]肝衰竭大鼠胃动力明显减退,其机制与胃窦肌间神经丛胆碱能神经分布减少、Cajal间质细胞减少及氮能神经分布增加有关。     

Gastrobiliary motility is not coordinated in patients with non-ulcer dyspepsia of normal gastric emptying time: simultaneous sonographic study

BACKGROUND: Disorders of the motor function of the upper gastrointestinal tract have been implicated in the pathogenesis of non-ulcer dyspepsia. Approximately 50% of patients with abdominal symptoms (without ulcer) have normal gastric emptying. Apart from gastric emptying, other mechanisms are very important in the etiology of non-ulcer dyspepsia. METHODS: Gastric emptying and gallbladder motility were simultaneously investigated in 16 patients with non-ulcer dyspepsia and in 15 healthy controls. Fasting blood samples were taken, and pepsinogen levels were assayed. RESULTS: Gastric emptying time, fasting antral diameter, and post-prandial antral diameter were not significantly different between the patients with non-ulcer dyspepsia and the controls. Fasting gallbladder volume, the time required to reach minimal gallbladder residual volume, minimal gallbladder residual volume, and the serum levels of pepsinogen were not significantly different. Simple linear regression was used to summarize the relationship between gastric emptying time and time required to reach minimal gallbladder residual volume. In the controls, the gastric emptying time and time required to reach minimal gallbladder residual volume were linearly related. However, in the patients with non-ulcer dyspepsia, they were not related. CONCLUSIONS: These observations suggest that disturbance of coordination between gastric emptying and gallbladder emptying is a cause of the symptoms of non-ulcer dyspepsia.     

Alteration of gastric myoelectrical and autonomic activities with audio stimulation in healthy humans

Cold or emotional stress was reported to affect gastric myoelectrical activity. The aim of this study was to investigate the effects of music or noise on gastric myoelectrical activity and autonomic function in healthy volunteers.

Material and methods

The study was performed in 10 fasted healthy volunteers and included 30 min at baseline, 30 min of classical music via headphones and 30 min of loud household noises via headphones. The electrogastrogram (EGG) readings were recorded simultaneously with the electrocardiogram (ECG) recording.

Results

Both classical music and noise altered the regularity of gastric slow waves. The percentage of normal 2–4 cycles/min (cpm) waves was reduced from 77.9±4.7% at baseline to 66.9±5.4% during music (p<0.006) and 67.7±5.4% during noise (p<0.05). The reduction was attributed to a significant increase in bradygastria (15.8±3.9% versus 9.8±2.6%, p<0.04) with the music and a significant increase in arrhythmia (7.4±1.6% versus 2.0±1.1%, p<0.02) with the noise. The dominant frequency and power of the EGG were, however, not altered with either music or noise. Neither music nor noise had any effect on the autonomic function assessed by the heart rate variability.

Conclusions

Audio stimulation, with both music and noise, alters the rhythmicity of gastric slow waves. Classical music seems to increase bradygastria, whereas, household noise may increase arrhythmia. The effect of audio stimulation on the gastric slow wave does not seem to involve sympathetic or vagal efferent pathways assessed by the spectral analysis of heart rate variability.     

Single oral dose of cisapride accelerates gastric antral emptying in healthy humans: An ultrasonographic study

An ultrasonographic study of ten healthy volunteers was carried out to evaluate the effect of cisapride on gastric antral emptying. More than 1 week after the measurement of the baseline emptying rate, cisapride was given at a single oral dose of 5 mg 30 minutes before intake of a balanced liquid test meal (5 ml/kg body weight). To determine the time to half emptying (T1/2), an exponential curve was extrapolated for the elimination phase of the gastroantral sagittal cross-sectional area plotted against time. The T1/2 was reduced by 18.5% after cisapride, from 62.6±4.3 to 51.0±4.4 min (P=0.0284). We conclude that a single oral dose of 5mg of cisapride significantly accelerates the gastric antral emptying rate in healthy humans.     

Ultrasonographic assessment of gastric motility in diabetic gastroparesis before and after attaining glycemic control

Background Glycemic control is important for maintaining gastric motility in diabetic patients, but gastric motility has not yet been studied ultrasonographically in relation to glycemic control.Methods We made such observations before and after establishing glycemic control in diabetic patients with gastroparesis. We studied 30 diabetic patients with upper abdominal digestive symptoms who were hospitalized for correction of poor blood sugar control and who underwent upper digestive tract endoscopy to rule out structural causes such as gastric/duodenal lesions. Gastric motility was evaluated by transabdominal ultrasonography, using a test meal, before and after attainment of glycemic control (within 3 days after admission and 3 days before discharge). Also, upper abdominal digestive symptoms present on admission and at discharge were compared.Results After glycemic control was established, contractions of the antral region were more frequent than before the attainment of control (8.93 ± 1.17/3 min vs 7.63 ± 2.22/3 min, respectively; P < 0.001). Glycemic control also significantly improved gastric emptying (before glycemic control, 49.2 ± 14.8%; after, 67.1 ± 11.5%; P < 0.001). This was also true for the motility index, concerning antral gastric contractility (before control, 2.97 ± 1.57; after, 3.75 ± 1.09; P < 0.05). Upper abdominal symptom scores were also significantly lower after attainment of control than before (0.47 ± 0.78 vs 3.17 ± 2.00, respectively; P < 0.001).Conclusions These findings suggest that attaining glycemic control improves gastric motility and attainments upper abdominal symptoms in diabetic patients with gastroparesis.     

Role of cholecystokinin in the regulation of liquid gastric emptying and gastric motility in humans: studies with the CCK antagonist loxiglumide

Background—Exogenous cholecystokinin (CCK)inhibits antral motility and slows gastric emptying (GE) but the effectof endogenous CCK on the gastric motor mechanisms responsible for GEremains unclear.
Methods—The effect of the CCK-A antagonistloxiglumide (LOX) on GE and motility was studied using magneticresonance imaging in six healthy volunteers after ingestion of 500 mlIntralipid 10% (550 kcal). Subjects were studied in the supineposition on two occasions during intravenous infusion of LOX(66 µmol/kg/h for 10 min followed by 22 µmol/kg/h) or placebo. GEwas determined every 15 minutes using transaxial abdominal scans andmotility was studied by means of 120 coronal scans, 1.2 seconds apart. For each coronal image the proximal and distal (antral) diameters weremeasured at a fixed point in the stomach to determine contraction frequency (ACF) and amplitude (AMP).
Results—GE was faster during LOX infusion thanplacebo (t_1/2 31 (22) versus 115 (67) minutes, p<0.03).There was little variation in the diameter of the proximal stomach witheither LOX or placebo. In the distal stomach marked contractileactivity was observed during LOX (ACF 2.9 (0.2) versus 1.5 (2.9) duringplacebo, p<0.01). AMP also increased during LOX compared with placebo(56 (22)% versus 27 (16)%, p<0.001).
Conclusion—The increases in antral motility arelikely to contribute to the acceleration of GE and suggest that CCK mayregulate GE by acting on the distal stomach although an effect on theproximal stomach cannot be excluded.

Keywords:loxiglumide; magnetic resonance imaging; gastricemptying; gastric motility; antral contraction

     

Gastric motility is an important factor in the pathogenesis of indomethacin-induced gastric mucosal lesions in rats

Effects of atropine, cimetidine, and 16,16-dimethyl prostaglandin E₂ (16,16-dmPGE₂) on indomethacin-induced gastric lesions were investigated in rats by correlating their effects on gastric acid and HCO^}-₃ secretion and motility. Subcutaneously administered indomethacin (25 mg/kg) produced gastric mucosal lesions within 4 hr. In parallel studies, an equivalent dose of indomethacin inhibited gastric HCO^}-₃ secretion, and stimulated gastric motor activity measured as intraluminal pressure recordings, whereas acid secretion was unaffected. The lesions induced by indomethacin were significantly prevented by three agents: cimetidine (100 mg/kg), which reduced acid secretion; atropine (1 mg/kg), which reduced acid secretion and gastric motility; and 16,16-dmPGE₂ (10 g/kg), which reduced acid secretion and motility and increased gastric HCO^– ₃ secretion. If acid (150 mM HCl) was infused into the stomach (1.2 ml/hr) during indomethacin treatment, only the latter two agents significantly prevented the formation of gastric lesions in response to indomethacin. Since only the effect on gastric motility was common to these two agents (atropine and 16,16-dmPGE₂), the increased gastric motility may be an important pathogenetic factor in indomethacin-induced gastric lesions. The presence of acid as well as a deficiency of endogenous PGs may be prerequisite for later extension of the lesions but cannot account for the induction of mucosal lesions in rats following administration of indomethacin.     

Gastric emptying of solids but not liquids is decreased in rats with chronic renal failure

Severe gastric complications occur in uremic patients, yet few studies have addressed the effect of chronic renal failure (RF) on gastric physiology. In the present study, we investigated: (1) the effect of RF on gastric emptying of liquids and solids in awake rats, (2) the motor function in the gastric corpus, and (3) the role of nitric oxide in any alterations in gastric motor function in uremic rats. RF was induced by partial kidney infarction. RF had no effect on gastric emptying of liquids but significantly inhibited gastric emptying of solids by 68%.N-Nitro-l-arginine, an inhibitor of nitric oxide (NO) synthesis, had no effect on the reduced gastric emptying of solids in RF rats. RF rats showed an altered pattern of gastric motility compared to sham-operated rats. These data suggest that RF induced an inhibition of gastric emptying of solids, but not liquids. However, NO does not seem to play a role in this inhibition.This work was supported by NIH grant DDK 41004 (H.E.R.) and the CURE/UCLA Digestive Disease Core Center DDK 41031 (Animal and Gastrointestinal Blood Flow Cores). E.Q. was the recipient of a Fogarty International Fellowship Award (NIH 1 FO5 TWO4443-01) and a grant from the Conserja de Education, Cultura y Deportes of the Canary Islands Autonomous Government. J.B. was supported by a grant from Fondacio La Caixa, Spain.     

Effect of prepyloric gastric transection and anastomosis on sphincter of Oddi cyclic motility in conscious dogs

Purpose. We previously reported significant changes in sphincter of Oddi cyclic motility after proximal duodenal transection and anastomosis. However, the role of intrinsic myoneural continuity between the antrum and duodenum in this respect is not understood. The aim of this study was to elucidate the effects of prepyloric gastric transection on sphincter of Oddi motility in animals in the conscious state. Methods. Pressures in the bile duct, duodenum, stomach, and sphincter of Oddi and their response to an injection of cholecystokinin-octapeptide were measured in four conscious dogs, with a duodenal cannula, before and after gastric transection and anastomosis 1.5 cm proximal to the pylorus. Results. Gastric transection did not affect the initiation and propagation of the gastroduodenal migration motor complex. Biliary pressure (5.7 ± 0.15 to 5.5 ± 0.2 mmHg; P = 0.91), sphincter of Oddi basal pressure (10.6 ± 0.3 to 10.7 ± 0.2 mmHg; P = 0.97), and amplitude (26.0 ± 1.2 to 32.9 ± 1.7 mmHg; P = 0.304) did not change after gastric transection. Biliary pressure decreased from phase II to phase III of the duodenal migrating motor complex. Cholecystokinin-octapeptide inhibited sphincter of Oddi phasic waves before and after gastric transection. Conclusions. Intrinsic myoneural transection at the prepyloric region does not influence sphincter of Oddi cyclic motility. Preservation of pyloroduodenal myoneural continuity in pylorus-preserving gastrectomy would be beneficial to maintain normal sphincter of Oddi motility. Received: October 30, 2000 / Accepted: February 23, 2001     

Plasma homocysteine is related to folate intake but not training status

BACKGROUND AND AIM: Lifestyle including intakes of several essential nutrients and physical activity are of particular interest in reducing plasma total homocysteine concentration (tHcy), a risk factor for cardiovascular diseases. The aim of this study was to determine in athletes, whether dietary factors such as intakes of folate, vitamin B6 and B12 were associated with lower plasma tHcy, and whether this depended on daily energy expenditure (EE) and type of physical activity performed (aerobic, anaerobic, intermittent). METHODS: Seventy-four well-trained athletes completed 7-day food and activity records in a cross-sectional study. Blood was sampled on day 8. RESULTS: Percentage of vegetal protein, vitamin B6, and folate intakes were higher and tHcy was lower (1) in athletes with high EE (> 16.72 MJ/d) compared to athletes with lower EE; (2) in aerobic athletes compared to intermittent athletes and sedentary subjects. After backward step by step analysis, folate intake was the only significant variable retained in the model to explain tHcy variability. Moreover, after introducing folate intake as a covariate in ANOVA tests, group effects on tHcy were no longer significant. Nutrient density of folate was inversely correlated to tHcy in athletes (r = -0.33; P = 0.004). CONCLUSION: High energy intake (> 16.72 MJ/d) allows the necessary folate intake (> 500 microg/d) for tHcy decrease to occur, which is moreover favored by aerobic activity. The mechanism underlying low tHcy in relation to high EE could only play a minor role when compared to the effect of dietary folate intake on tHcy.     

Postischemic intestinal motility in rat is inversely correlated to length of ischemia

An inverse correlation between postischemic gastrointestinal motility and the length of intestinal ischemia was found in an animal model. Intestinal ischemia was caused without concurrent laparotomy and for a predetermined time period (ischemia time) by pulling on an external nylon thread that was threaded through a double-lumen catheter. This catheter was passed into the abdominal cavity to encircle the superior mesenteric artery. Gastrointestinal motility was determined by the introduction of a color-marked meal into the animal's stomach and the measurement of the proportionate length of the small bowel filled with it (transit index). This simple and reliable animal model can also be used for the evaluation of techniques and pharmacological manipulations aimed at modulation of the effects of intestinal ischemia on intestinal motility and its consequences.     

Endogenous oestradiol but not testosterone is related to coronary artery disease in men

Objectives Men die of coronary artery disease (CAD) more often than women. There is evidence that testosterone either is neutral or has a beneficial effect on male cardiovascular disease. The role of oestrogens in male CAD has been less studied. This study was carried out with the purpose of evaluating the relationship between sex hormone levels and CAD. Design Case–control study. Participants Men (aged 40–70) submitted to coronary angiography. A 70% occlusion of at least one major coronary artery defined the cases; subjects with ≤50% occlusion constituted the control group. Measurements Blood samples were collected for total testosterone (TT), oestradiol, luteinizing hormone, follicle‐stimulating hormone, sex hormone‐binding globulin, lipid profile and albumin measurements. Bioavailable and free testosterone, free androgen index (FAI) and free oestrogen index (FEI) were calculated. Oestradiol and TT levels were examined as terciles, based on the whole study population. Results Of the 140 patients included, 72 were cases and 68 were controls. The baseline characteristics of the two groups were similar, except for the older age and lower LDL‐C in the cases. Oestradiol and FEI but not total, bioavailable and free testosterone and FAI correlated positively with CAD. After adjustments for potential confounders, oestradiol remained statistically significant. The prevalence of CAD was significantly higher in the 3rd than in the 1st tercile of oestradiol. Conclusion In this study, men with CAD had higher oestradiol and FEI levels. Additional studies are needed to clarify the direction of causality and possible underlying mechanisms.     

Relation between histologic gastritis and gastric motility in Japanese patients with functional dyspepsia: evaluation by transabdominal ultrasonography

BACKGROUND: Whether mucosal inflammation affects gastric motility in patients with functional dyspepsia (FD) is controversial. Few reports discuss gastric motility in relation to histologic gastritis. We examined the relation between gastric motility and histologic gastritis in Japanese patients with FD. METHODS: Subjects were 198 patients examined by ultrasonography (US) and endoscopic biopsy. Histologic gastritis scores were compared to three US gastric motility indices: the motility index (MI), gastroduodenal reflux index (RI), and gastric emptying rate (GER). In cases of gastritis with a high inflammation score (score 2-3), the macrophages in biopsy specimens were counted and compared to the motility indices. RESULTS: Of the 198 patients, 159 were Helicobacter pylori positive. Comparison of 39 age-and sex-matched H. pylori-positive and 39 H. pylori-negative patients showed that the MI was lower in H. pylori-positive patients (6.78+/-2.17 vs. 7.63+/-2.35, P<0.05), and the RI was higher (5.64+/-4.70 vs. 2.13+/-2.58, P<0.01). Among H. pylori-positive patients, US revealed a decreased MI in patients with a high inflammation score (score 2-3) in the antrum compared with the MI of those with a low inflammation score (score 0-1) (6.52+/-2.38 vs. 7.82+/-1.89, P<0.01). The number of macrophages was not associated with motility indices in patients with a high inflammation score. CONCLUSION: Histologic gastritis with severe inflammation may inhibit gastric motility.     

Telomere erosion is independent of microsatellite instability but related to loss of heterozygosity in gastric cancer

AIM: To correlate the length of the telomere to microsatellite instability (MSI) and loss of heterozygosity (LOH) of APC, MCC and DCC genes in gastric carcinomas. METHODS: Telomeric restriction fragment (TRF) length of gastric cancer was measured with Southern blot. LOH of APC, MCC and DCC genes, microsatellite instability (MSI) and frameshift mutation of hMSH6, TGF-betaRII and BAX genes were analyzed by PCR-based methods. RESULTS: Sixty-eight cases of sporadic gastric carcinoma were studied for MSI using five microsatellite markers. MSI in at least one locus was detected in 17 (25%) of 68 tumors analyzed. Frameshift mutations of hMSH6, TGF-betaRII and BAX were detected in 2,6 and 3 of gastric carcinomas respectively showing high MSI (> or = 2 loci, n = 8), but none was found in those showing low MSI (only one locus, n = 9) or MSS (tumor lacking MSI or stable, n = 51). Thirty-five cases, including all high MSI and low MSI, were studied for TRF. The mean TRF length was not correlated with clinicopathological parameters. No association was observed between TRF length and MSI or frameshift mutation. On the contrary, LOH at the DCC locus was related to telomere shortening (P<0.01). This tendency was also observed in APC and MCC genes, although there was no statistical significance. CONCLUSION: The development of gastric cancer can arise through two different genetic pathways. In high MSI gastric cancers, defective mismatch repair allows mutations to accumulate and generate the high MSI phenotype. In gastric cancers showing either low MSI or MSS, multiple deletions may represent the LOH pathway. Telomere erosion is independent of high MSI phenotype but related to the LOH pathway in gastric cancer.