Opposite effects of kappa-opioid agonists on gastric emptying of liquids and solids in dogs

The influence of oral (p.o.) administration of kappa-(U-50488, tifluadom) and mu- (morphine, DAGO) opioid substances on gastric emptying of liquids and solids in a standard canned dog food meal was evaluated using a double-radiolabeled technique in dogs fitted with gastric cannulas. One hour after feeding, 28.6% +/- 3.6% (mean +/- SD) of the solid phase and 27.1% +/- 8.6% of the liquid phase of the meal had been emptied. Both U-50488 and tifluadom given orally (0.01-0.1 mg/kg) significantly increased (p less than 0.05) the 1-h emptying of the solid phase of the meal by 23.1%-49.6%. In contrast, both drugs significantly reduced emptying of liquids. These effects were not reproduced when similar doses were given intravenously. Oral administration of morphine or DAGO (0.01-0.1 mg/kg) did not affect gastric emptying, whereas an inhibited emptying of solids was observed for morphine at a higher dose (1 mg/kg p.o.). At a dose of 100 micrograms/kg i.v. both naloxone and MR 2266 (0.1 mg/kg) abolished the effects of orally administered U-50488 on gastric emptying of solids and liquids. It is concluded that kappa- but not mu-agonists act locally to alter gastric emptying of a standard meal in dogs, having opposite effects on solid and liquid phases. A selective local stimulation of kappa mucosal or submucosal receptors of the gastroduodenal area may explain such effects.     

Gastric emptying of a solid-liquid meal in normal subjects: validity of the labeling (99mTc) of chicken liver by a multipuncture technic

For gastric emptying studies of a solid-liquid meal by the scintigraphic method, a valid isotope labeling method for each phase of the meal must be obtained. The aim of this study was to validate a simple chicken liver labeling method in normal subjects by multipuncture technic with 99mtechnetium. Labeling according to Meyer's method was chosen as a reference. Simultaneously, a study of the quality of liquid phase labeling by 111indium was done. The labeling process quality for each phase of the meal was assessed: a) in vitro, after incubation of the meal with human gastric juice (n = 12); b) in vivo, after meal ingestion and sequential collection of gastric contents by aspiration (n = 4). Furthermore, in 8 healthy volunteers, gastric emptying curves of the solid and liquid phases of the meal were determined scintigraphically and compared. Our results showed: a) for the solid phase: a good specificity of the marker, which was assessed in vitro and in vivo, after liver labeling with multipuncture technique (89 p. 100 and 92 p. 100 after 180 min, respectively); b) for the liquid phase: a good specificity of the marker in vitro and a poor specificity in vivo (82 p. 100 and 27 p. 100 after 180 min, respectively); c) similar half-gastric emptying times and cumulative percentages for the solid and liquid phases with both liver labeling methods. In conclusion, the multipuncture technique for chicken liver labeling may be used for gastric emptying studies in humans.     

The Effect of Erythromycin in Gastric Emptying of Solids and Hypertonic Liquids in Healthy Subjects

We report our study of the effect of erythromycin on gastric emptying of solid and liquid meals in 10 healthy subjects. On different occasions, subjects consumed either a radiolabeled 50% glucose solution, or a radiolabeled standard solid meal after placebo, and after receiving 200 mg of erythromycin intravenously. Erythromycin accelerated the gastric emptying of the hypertonic liquid meal by significantly decreasing the duration of lag phase ( p < 0.0001), by significantly increasing the emptying rate at the postlag period ( p < 0.001), and by significantly decreasing the duration of the postlag period ( p < 0.0001) and the meal remaining in the stomach at 15 ( p < 0.05), 30 ( p < 0.001), and 60 ( p < 0.01) min postprandially. In addition, erythromycin administration induced a significant plasma fall at 15 ( p < 0.05) and 30 ( p < 0.01) min and a significant increase in pulse rate at 15 and 30 min ( p < 0.01) after consumption of the hypertonic glucose solution, whereas three subjects experienced symptoms suggesting dumping syndrome. Furthermore, erythromycin administration enhanced the gastric emptying of solids by almost abolishing the duration of lag phase ( p < 0.0001) and by reducing the overall t_1/2 of emptying ( p < 0.0001), whereas less food was retained in the stomach at 60 ( p < 0.001) and 120 ( p < 0.0001) min postprandially. Conversely, the postlag t_1/2 of the solid meal emptying was not affected by erythromycin, as compared to placebo. We conclude that erythromycin has gastrokinetic properties, affecting the gastric emptying of both liquids and solids.     

Effect of fundus vagotomy on the gastric emptying of the solids and liquids of a meal in patients with and without postoperative duodenal ulcer recurrence

The effects of fundic vagotomy (FV) on gastric emptying in the solid and liquid phases of a meal were studied by an isotopic technique in 12 patients with duodenal ulcer. Postoperative results were compared with those obtained in the same subjects before FV and with control values obtained in an identical group of healthy subjects. Early gastric emptying (perprandial) of the two phases of the meal was enhanced by FV but the results failed to reach statistical significance. Gastric emptying of liquids, measured during the 3 h following the end of the meal, was not significantly modified by FV (half-emptying times: 62 +/- 5 min before FV, 75 +/- 8 min after and 65 +/- 7 min for controls). That of solids was significantly delayed by FV (per cent emptied by min: 0.50 +/- 0.02 p. 100 before FV, 0.40 +/- 0.03 p. 100 after, and 0.49 +/- 0.02 p. 100 for controls); this delay was found in all but one patient, but the difference was very slight. Eleven of the 12 investigated patients cured by the operation, were compared with 6 subjects presenting with post FV recurrence: gastric emptying rates of solids (0.41 +/- 0.02 p. 100/min and 0.47 +/- 0.07 p. 100/min) and half emptying times of liquids (72 +/- 10 min and 61 +/- 10 min) were not significantly different. Thus, the gastric emptying rate of an ordinary meal remains practically unchanged by FV and postoperative recurrences of duodenal ulcer cannot be explained by alteration of gastric evacuation.     

Influence of acid-pepsin secretion on gastric emptying of solids in humans: studies with cimetidine.

The commonly accepted model for gastric emptying suggests that the 'antral mill' is responsible for the triturition and subsequent emptying of solid food from the stomach. Little is known about the contribution to solid emptying made by other digestive mechanisms such as acid-pepsin secretion. We have investigated the effect of inhibiting gastic secretion on the rate at which a solid test meal emptied from the stomach. Using a radiolabelled beefburger, we performed paired gammacamera studies on consecutive days in 10 fasted, healthy volunteers to compare gastric emptying of the test meal with and without oral cimetidine (400 mg 1 hour before the test, 800 mg at the start of the meal). Inhibition of acid-pepsin secretion by cimetidine was associated with an appreciable delay in the rate of emptying of the burger from the stomach (T50 cimetidine 187 (16) min (mean (SEM); T50 no cimetidine 146 (15) min; p less than 0.01, paired t test). This delay was related to a change in the slope of the emptying profile and was not associated with a prolonged lag phase. These results may be explained by the relative achlorhydria and reduced pepsin activity induced by cimetidine impairing the breakdown of solid food into particles small enough to leave the stomach.     

Gastric and oesophageal emptying in insulin-dependent diabetes mellitus

Abstract Gastric emptying of a digestible solid and liquid meal and oesophageal emptying of a solid bolus were measured with scintigraphic techniques in 45 randomly selected insulin-dependent diabetics and in 22 control subjects. In the diabetics, the relationships between oesophageal emptying, gastric emptying, age, duration of diabetes mellitus, upper gastrointestinal symptoms, glycaemic control and the complications, autonomic neuropathy, peripheral neuropathy and retinopathy were examined. The lag period before solid food left the stomach was not significantly different in diabetics compared with control subjects, but the percentage retention of solid food at 100 min was greater ( P < 0.001) in the diabetic subjects. Both the early phase (percentage retention at 10 min) and the 50% emptying time for liquid gastric emptying were delayed ( P < 0.001) in the diabetic subjects. Of the diabetics, 58% had delayed gastric emptying of either the solid and/or the liquid meal; oesophageal emptying was delayed in 42%. Upper gastrointestinal symptoms correlated poorly with both gastric and oesophageal emptying. Oesophageal emptying, solid gastric emptying and the liquid 50% emptying time correlated with the severity of autonomic nerve dysfunction ( P < 0.05). The early phase of liquid emptying (retention at 10 min) was significantly slower ( P < 0.05) in patients with mean plasma glucose concentrations of > 15 mmol/l during the gastric emptying test and the lag period for solid emptying correlated with both the glycosylated haemoglobin and mean plasma glucose concentrations.     

糖尿病病人胃排空及小肠运动时间变化的研究

目的　了解糖尿病病人液体和固体混合餐后胃排空及固体食物在小肠的运行情况。方法　采用双核素标记液体和固体后 ,用SPECT探头采集感兴趣区图像 ,计算胃排空和小肠运行时间指标。结果　糖尿病病人固体全胃半排空 近端胃半排空 远端胃最大计数时间均较正常人明显延迟 ,4 0 %～ 4 4 %病人超过正常范围 ,延迟相时间均数变化不明显 ,但 4 8%超出正常范围 ,液体排空各指标变化不明显。而小肠运行时间在糖尿病病人延迟明显。结论　糖尿病病人固体食物胃肠运行时间延迟 ,而液体胃排空无异常变化。     

Effect of cisapride on gastric and esophageal emptying in insulin-dependent diabetes mellitus

The effects of cisapride on gastric emptying, esophageal emptying, gastrointestinal symptoms, and glycemic control were evaluated in 20 insulin-dependent diabetics who had delayed gastric emptying of the solid or liquid component of a meal, or both. A double-isotope technique was used to measure gastric emptying, and esophageal emptying was measured as the time for a bolus of the solid meal to enter the stomach. On 2 days each patient received cisapride (20 mg) or placebo orally, 60 min before an esophageal and gastric emptying test. A third gastric and esophageal emptying test was performed after each patient had orally taken 10 mg of cisapride or placebo q.i.d. for 4 wk. Single-dose cisapride increased esophageal emptying (p less than 0.01) and both solid and liquid gastric emptying (p less than 0.001). The response to cisapride was most marked in patients with the greatest delay in esophageal and gastric emptying (p less than 0.05). After administration of cisapride for 4 wk, gastric emptying of solid and liquid were faster (p less than 0.001), but esophageal emptying was not significantly different from the placebo test. Upper gastrointestinal symptoms were less after cisapride (p less than 0.05), whereas there was no change on placebo (p greater than 0.2). Plasma glucose and glycosylated hemoglobin concentrations were not different after cisapride compared with placebo. These results indicate that single-dose cisapride increases esophageal emptying in insulin-dependent diabetics and that chronic administration of cisapride is effective in the treatment of diabetic gastroparesis.     

Effects of cisapride on gastric and esophageal emptying in progressive systemic sclerosis

The effects of cisapride on gastric emptying, esophageal emptying, and gastrointestinal symptoms were evaluated in 8 patients with progressive systemic sclerosis who had delayed gastric emptying of the solid or liquid component of a meal, or both. A double-isotope technique was used to measure gastric emptying, and esophageal emptying was measured as the time for a bolus of the solid meal to enter the stomach. Gastrointestinal symptoms were assessed by a questionnaire. On 2 days each patient received cisapride (10 mg) or placebo intravenously, 5 min before an esophageal and gastric emptying test. After these 2 days each subject took cisapride (10 mg q.i.d., p.o.) for 1 mo. Cisapride improved solid and liquid gastric emptying (p less than 0.001), but had no significant effect on esophageal emptying (p less than 0.1). Upper gastrointestinal symptoms were reduced after cisapride (p less than 0.001), and no side effects were reported. These results indicate that gastroparesis is a treatable cause of morbidity in progressive systemic sclerosis.     

Influence of food and marker length on gastric emptying of indigestible radiopaque markers in healthy humans

A simple, noninvasive radiographic method was used to investigate the influence of food and of marker length on gastric emptying of indigestible solids. Ten healthy human subjects who had fasted for 12 h exhibited more rapid emptying when solid radiopaque markers were ingested with water than they did when markers were ingested with a 400-kcal solid and liquid meal. Mean (+/- SE) emptying of markers that were 10 mm in length averaged 55% +/- 15%, 97% +/- 3%, and 100% 1, 2, and 4 h after ingestion of the markers with water, compared with 4% +/- 2%, 32% +/- 11%, and 64% +/- 12% emptying 1, 2, and 4 h after ingestion of markers with the meal (p less than 0.05). Ingestion of a second and third test meal significantly prolonged gastric emptying of indigestible markers (p less than 0.05). No significant difference in emptying of the 10- and 2-mm markers from the stomach was detected. These experiments indicate that gastric emptying of indigestible solids in humans is strongly influenced by food intake, but not by the particle lengths studied.     

Stress-induced changes in gastric emptying, postprandial motility, and plasma gut hormone levels in dogs

The influence of acoustic stress on postprandial gastrointestinal motility, gastric emptying, and plasma gastrin, pancreatic polypeptide, motilin, and somatostatin was evaluated in conscious dogs. Six dogs were equipped with strain-gauge transducers and were exposed from 1-3 h after the meal to prerecorded music (80-90 dB broad frequency noise), which produced a significant (p less than or equal to 0.05) lengthening of the gastric (31.2%) and jejunal (37.0%) postprandial pattern. In 4 other dogs with gastric cannula, a 2-h session of acoustic stress beginning just after eating a radiolabeled standard meal induced a slowing of gastric emptying of both liquid (45.7%) and solid (47.1%) phases of the test meal when measured 0.5 h after feeding. In contrast, when measured 2 h after feeding, similar values of gastric emptying of liquids and solids were observed in stressed and control animals. Compared with controls, the postprandial increases of plasma gastrin and pancreatic polypeptide levels were significantly enhanced in stressed animals and occurred early (15 min after the meal). Although postprandial decrease in plasma motilin was unchanged by acoustic stress, the rise in plasma somatostatin level was significantly (p less than or equal to 0.05) prolonged in stressed dogs. These results indicate that acoustic stress affects gastric and intestinal postprandial motility in dogs, delaying the recovery of the migrating motor complex pattern, inducing a transient slowing of gastric emptying, and enhancing the feeding-induced release of gastrin, pancreatic polypeptide, and somatostatin. Such hormonal changes might be due to a direct effect of stress rather than being the consequence of acoustic stress-induced slowing of gastric emptying.     

Human migrating myoelectric complex in relation to gastrointestinal transit of a meal.

Feeding interrupts the migrating myoelectric complex in most mammals. This study aimed to assess whether resumption of the migrating myoelectric complex in the human duodenum after eating was related to the gastrointestinal transit of the meal. Five healthy subjects participated in the study. After eating a radiolabelled test meal consisting of mixed liquid and solids, duodenal myoelectric activity and gastrointestinal transit of the meal were determined simultaneously. In spite of considerable variation in entire gastric emptying time between subjects (range 2.5-5.0 hours), significant correlation was found between the completion of gastric emptying and the resumption of duodenal phase III activity within subjects (p less than 0.01). A new technique for recording the duodenal myoelectric activity was used.     

Effect of obesity and major weight reduction on gastric emptying

BACKGROUND: An enhanced gastric emptying rate might reduce the satiating effect of food and thereby promote obesity. Gastric emptying rate has previously been compared between obese and lean subjects with conflicting outcome. OBJECTIVE: Comparison of gastric emptying rate in lean and obese subjects before and after a major weight reduction. DESIGN: The study was designed as a case-control study comparing obese and lean subjects and a subsequent comparison of obese subjects before and after a dietary induced major weight reduction. METHOD: Gastric emptying rate following a solid test meal was estimated scintigraphically for 3 h using the left anterior oblique projection. SUBJECTS: Nineteen non-diabetic obese (mean BMI=38.7 kg/m2) and 12 lean (mean BMI=23.1 kg/m2) males matched for age and height. All obese subjects were re-examined after a mean weight loss of 18.8 kg (95% CI, 14.4-23.2) achieved by 16 weeks of dietary intervention followed by 8 weeks of weight stability. RESULTS: When comparing obese and lean subjects no differences were seen in overall 3 h emptying rate (30.3% per hour vs 30.5% per hour). However, a trend towards a higher percentage gastric emptying during the initial 30 min was seen in the obese when compared to lean subjects (24.0% vs 17.8% of the test meal; P=0.08). Weight loss was associated with a reduction in percentage gastric emptying during the initial 30 min (from 24.0% to 18.3% of the test-meal; P<0. 02), whereas the overall 3 h emptying rate was unaffected (30.3% vs 30.9% per hour). Neither initial or overall emptying rate differed between reduced-obese and lean subjects. CONCLUSION: Overall 3 h gastric emptying rate was similar in obese and normal weight males, and unaffected by a major weight loss. However, percentage gastric emptying during the initial 30 min for a solid meal appeared to be increased in obese males and was normalized after a major weight reduction.     

急性逆行胃电刺激对肥胖患者胃容受性、胃排空和胃肠激素释放的影响

目的 观察急性逆行胃电刺激(RGES)对肥胖患者胃容受性、胃排空和胃肠激素释放的影响.方法 选取肥胖患者16例.第1天经胃镜放置胃黏膜电极,第2天进行液体餐负荷试验、标准固体餐胃排空试验,每次试验开始前30min及试验过程中给予RGES.标准固体餐胃排空试验前后检测血清瘦素、生长激素释放肽、抵抗素和肽YY.第3天给予假性刺激,通过自身对照比较急性RGES对相关指标的影响.结果 16例患者体重指数为(32.90±2.99)kg/m2.急性RGES明显减少患者达到饱感所进液体餐量[分别为(460±148)ml和(630±219)ml,t=-7.200,P＜0.01]和最大耐受程度进餐量[分别为(699±215)ml和(926±295)ml,t=-5.390,P＜0.01],对标准固体餐胃半排空时间、1h及2h标准固体餐存留率的影响分别为(109±26)min和(103±31)min,t=1.009,P=0.329;(63.37±9.75)%和(59.73±12.87)%,t=1.834,P=0.087;(42.22±13.97)%和(38.33±16.87)%,t=1.780,P=0.095.急性RGES后胃肠激素水平/刺激前水平和假性胃电刺激后水平/刺激前水平分别为瘦素(1.03±0.34和1.08±0.38,t=-0.386,P=0.705)、生长激素释放肽(0.99±0.11和0.98±0.12,t=0.413,P=0.685)、抵抗素(1.11±0.25和0.99±0.24,t=1.753,P=0.100)、肽YY(1.56±0.71和1.33±0.61,t=1.402,P=0.181).结论 急性RGES通过降低胃容受性显著减少肥胖患者的进食液体餐量,一定程度上减缓胃排空,但对相关胃肠激素释放无显著影响.

Abstract：

Objective To observe the effect of acute retrograde gastric electrical stimulation (RGES) on gastric accommodation,emptying and gastrointestinal hormones releasing in obese patients. Methods Sixteen obese patients were examined. On the first day,a pair of mucosal gastric electrodes was placed under endoscope. The liquid meal load test and the standard solid meal gastric emptying test were carried out on the second day. RGES was performed starting at 30 minutes before each test and through the whole testing process. The serum leptin,ghrelin,resistin and peptide YY were examined before and after the standard solid meal gastric emptying test. On the third day,sham stimulation was given. The effect of acute RGES on related index was compared by self-control.Results BMI of the 16 patients was (32. 90±2. 99) kg/m2. Acute RGES significantly reduced the liquid meal volume of fullness [(460±148) ml and (630±219) ml,t=-7. 200,P＜0. 01] and the maximal tolerable meal volume [(699±215) ml and (926±295) ml,t=- 5. 390,P＜0. 01]. The effects of RGES and sham RGES on half-emptying time of standard solid meal was (109±26) min and (103±31) min (t=1. 009,P= 0. 329);on the retention rate of standard solid meal at one hour and two hour was (63. 37±9. 75)% and (59. 73±12.87)% (t=1. 834,P= 0. 087),(42.22±13.97)%and (38. 33±16. 87)% (t= 1.780,P= 0. 095),respectively. The ratio of gastrointestinal hormones after and before the stimulation also of the sham stimulation,leptin was 1. 03±0. 34 and 1. 08±0. 38(t=-0.386,P=0. 705),ghrelin was 0. 99±0. 11 and 0. 98±0. 12 (t= 0. 413,P=0.685),resistin was 1. 11±0. 25 and 0. 99±0. 24 (t= 1. 753,P= 0. 100),and peptide YY was 1. 56±0. 71 and 1. 33±0. 61 (t=1. 402,P= 0. 181). Conclusions In obese patients,acute RGES significantly reduce the liquid meal volume by lower gastric accommodation,to certain extent which will delay gastric emptying. There is no significant influence on gastrointestinal hormones releasing.     

131I-白蛋白固体食物标记物用于研究胃排空

目的评价１３１ＩＢＳＡ作为胃固体排空标记物的稳定性和临床应用价值．方法以１３１ＩＢＳＡ和９９ｍＴｃＤＴＰＡ分别作为混合餐固、液体食物的标记物，检测３５例慢性胃炎患者和１０名健康志愿者的胃排空，其中２例受检者１周内进一步用９９ｍＴｃＳＣ复查固体排空，比较两次固体排空过程的相关性．在体外对上述３种放射性标记物在胃液、１ｍｏｌ／ＬＮａＣｌ和０１ｍｏｌ／ＬＨＣｌ溶液中消化２ｈ，检测其稳定性．结果１３１ＩＢＳＡ和９９ｍＴｃＳＣ标记的固体食物经消化后的脱标率分别＜２８７％和４６３％，９９ｍＴｃＤＴＰＡ吸附于固相的吸附率＜８３６％．固、液体排空曲线明显不同，固体排空有明显的延迟期，半排空时间较长，慢性胃炎患者固、液体排空时间均较正常对照组延长，两种固体标记物的排空曲线相似，相关性为ｒ＝０９８９（Ｐ＜００１），前、后两次排空相比，最大差值为９２％，最小差值仅为０８％．结论１３１ＩＢＳＡ固体标记物稳定性较好，可用于临床胃排空的检测．     

Inhibition of gastric secretion and motility by simulated upper gastrointestinal haemorrhage: a response to facilitate haemostasis?

As gastric acid and pepsin inhibit blood coagulation and platelet aggregation it is surprising that most upper GI haemorrhages stop spontaneously. To investigate this paradox we have studied acid and pepsin secretion, gastric motility and GI hormones after simulated upper GI haemorrhage. In seven healthy volunteers intraduodenal infusion of 160 ml autologous blood decreased pentagastrin stimulated submaximal acid secretion (mmol/h) from 30.0 (3.2) (mean (SE] in the hour preceding infusion to 21.4 (3.7) in the hour following infusion (p less than 0.02), representing a mean reduction in acid output of 30%. Pepsin output (mg/h) was also decreased from 207.5 (67.7) (mean (SE] in the hour preceding blood infusion to 135.7 (54.7) in the hour after infusion (p less than 0.02) representing a mean reduction in pepsin output of 43%. In six volunteers gastric emptying of a liquid meal was delayed after intraduodenal blood infusion compared with intubation alone with the emptying time (min) to half volume (t 1/2) being prolonged at 75.0 (8.2) (mean (SE] after blood infusion compared with 35.5 (6.6) after intubation alone (p less than 0.02). Plasma GIP concentrations (ng/l) increased to peak levels of 127.9 (62.7) (mean (SE] after intraduodenal blood infusion compared with the pre-infusion value of 58.3 (2.3) (p less than 0.02). These changes may represent protective physiological responses to facilitate haemostasis.     

Effect of cisapride on gastric emptying in dyspeptic patients

The effect of the new gastrokinetic agent cisapride on gastric emptying was evaluated in 17 dyspeptic patients using the dual radionuclide technique. Eight patients with idiopathic dyspepsia and nine postsurgical dyspeptic patients were studied and compared to a control group. Gastric emptying of solids and liquids was determined after ingestion of a standardized meal using^99mTc-sulfur colloid scrambled eggs as the solid phase and [¹¹¹In]DTPA-labeled water as the liquid phase. Following a basal study and on a separate occasion, each patient received an intravenous bolus of 10 mg of cisapride after ingestion of the test meal; 10 of the patients were restudied after a two-week period of chronic oral administration of the drug (10 mg four times a day). Baseline gastric emptying of solids was significantly delayed in idiopathic and postsurgical patients; liquid emptying was only delayed in the postsurgical group. Intravenous and oral administration of cisapride significantly shortened gastric emptying in both groups. In all but one patient, the clinical improvement was confirmed by the test. Cisapride appears to be a good alternative to metoclopramide and domperiodone in the treatment of dyspeptic patients. The dual radionuclide technique appears to be a useful physiologic tool for evaluating and predicting the efficacy of a gastric prokinetic therapy in man.     

The effect of bacterial lipopolysaccharide on the gastric emptying of rats: a pretreatment evaluation using dexamethasone and methylene blue

BACKGROUND: The nitric oxide might be a putative mediator of the decrease in gastric emptying induced by bacterial lipopolysaccharide in rats. AIM: For that, we evaluated the effect of the pretreatment intravenous with dexamethasone and methylene blue in the retardation process of gastric emptying induced by intravenous application of lipopolysaccharide in rats. Dexamethasone has been shown to inhibit the induction of NOS II (induced NO-synthase) while the methylene blue, that blocks the soluble guanylyl cyclase, inhibits nitric oxide synthases and, in addition, inactivates nitric oxide directly. MATERIAL AND METHODS: Male Wistar rats, specific patogenic free, were used after a 24 hour fast and 1 hour-water withdrawn. The pretreatment was performed using dexamethasone solutions (3 and 6 mg/kg), methylene blue (2 mg/kg) or sterile vehicle. The treatment consisted in the application of lipopolysaccharide (50 mug/kg) or vehicle. The time period between the pretreatment and treatment was 10 minutes, excluding the study with dexamethasone 6 mg/kg that was 1 hour. The gastric emptying was evaluated 1 hour after the lipopolysaccharide application, except for two studies with dexamethasone 3 mg/kg in which the time periods were 2 and 8 hours. A saline solution containing phenol red was used as the test meal. The gastric emptying was determined by measuring gastric retention 10 minutes after the orogastric infusion of the test meal. RESULTS: The pretreatment with dexamethasone or methylene blue and treatment with vehicle did not have effect in the gastric emptying comparing to the control group. We found that pretreatment with dexamethasone in the studies for 1 hour and 2 hours did not interfere in the retardation of the gastric emptying produced by endotoxin. Nevertheless, in the eighth period study with this drug there was a significant reduction of gastric retention in the endotoxin-treated animals in relation to the unpretreated ones. Meanwhile, the pretreatment with the methylene blue completely blocked the action of endotoxin on the gastric emptying in rats. CONCLUSION: These results suggest a possible involvement of nitric oxide on the effect of lipopolysaccharide in rat gastric emptying.     

Liquid and solid gastric emptying in adults treated for Hirschsprung's disease during early childhood

OBJECTIVE: Dysmotility of the upper gastrointestinal tract has been reported in children with Hirschsprung's disease. In the present study, gastric emptying was studied in adult patients with Hirschsprung's disease to elucidate whether there is a persisting involvement of the upper gastrointestinal tract in this group of patients. MATERIAL AND METHODS: Gastric emptying of caloric liquids and solids was studied in 16 adult patients with surgically treated Hirschsprung's disease during early childhood and in age-matched controls. To examine liquid emptying, the paracetamol absorption test was applied using a meal containing glucose, lactose, maize oil, water (2020 kJ) and paracetamol. To examine solid emptying, the 13C gastric emptying breath test was applied using a meal containing white bread, margarine, a one-egg omelette (1050 kJ) and [13C]-octanoic acid. Gastrointestinal symptoms were recorded according to a standardized questionnaire. RESULTS: For liquid meal emptying, the time until emptying commenced was 8.1+/-1.9 and 2.9+/-0.9 min (mean+/-SE) in patients and controls, respectively (p=0.02). Thereafter, the first 25% of the meal emptied in 6.8+/-0.8 and 12.1+/-1.1 min in patients and controls, respectively (p=0.0005). The overall emptying rate tended to be delayed in patients compared with controls (p=0.06). For the solid meal, a delay in emptying was evident (p=0.02). The patients reported more symptoms from the upper gastrointestinal tract than the controls, but the symptoms were not significantly related to the emptying pathology demonstrated. CONCLUSIONS: The present study demonstrates that adult patients with Hirschsprung's disease have an abnormal pattern of gastric emptying, indicating persisting involvement of the upper gastrointestinal tract.     

The effects of cisapride on gastric and oesophageal emptying in dystrophia myotonica

The effects of cisapride on gastric emptying, oesophageal emptying, and gastrointestinal symptoms were evaluated in 10 patients with dystrophia myotonica who had delayed gastric emptying of the solid and/or liquid component of a meal. A double isotope technique was used to measure gastric emptying and oesophageal emptying was measured as the time taken for a bolus of the solid meal to enter the stomach. Gastrointestinal symptoms were assessed by a questionnaire. Gastric and oesophageal emptying and gastrointestinal symptoms were measured before and when each subject had taken cisapride (10 mg, q.i.d., p.o.) for 4 weeks. Cisapride improved solid gastric emptying, and there was a non-significant trend for improved liquid emptying. Cisapride had no effect on oesophageal emptying. Upper gastrointestinal symptoms were less after cisapride and there was an increased frequency of bowel actions. No side effects were reported. These results indicate that gastroparesis is a treatable cause of morbidity in dystrophia myotonica.