Pattern Of Gastric Emptying Research Articles

Labelling procedure of antacid preparations using 99m Tc-pyrophosphate

A new radioisotopic labelling method of two antacid preparations containing magnesium and aluminium ions has been designed. 99mTc-pyrophosphate was used as tracer agent and, owing to the high labelling efficiency obtained (> 98%), no purification step was necessary. The stability of both labelled antacids was tested as well as their antacid capacity and their protein-binding capacity compared with the unlabelled samples. All these tests were satisfactory enough to consider this 99mTc labelling method a good tool for preparing labelled antacids that contain A1 3+ and/or Mg 2+ and so to evaluate the antacid gastric emptying pattern by means of scintigraphic studies.

The effect of food on cyclosporine absorption

The high lipophilicity of cyclosporine A (CsA) and the importance of bile for its absorption suggest that food may alter the absorption of CsA. Food has been reported to have varied effects on the absorption of CsA. Study methodology may explain the conflicting reports. Factors which were not well controlled in these studies include time post transplant, fat and caloric content of a meal, the inherent gastric emptying pattern of a patient, and concurrent disease processes which may alter gastric emptying. Based on available information, patients should be instructed to take their CsA consistently in relation to the timing and composition of meals in order to minimize absorption variability.

Comparative Effects of Duodenal and Heal Intubation on Gastric Emptying and Postprandial Antral, Pyloric, and Duodenal Motility

The influence of gastric and small-intestinal intubation on fed patterns of antropyloroduodenal motility and gastric emptying of a solid meal has been investigated in normal volunteers. In 10 subjects a manometric assembly was passed as far as the fourth part of the duodenum; in 8 other subjects the terminal ileum was intubated; and a further 8 subjects were not intubated. The manometric assemblies were similar, apart from their length, and both incorporated a sleeve/side hole assembly located across the pylorus. All subjects ingested a meal of 100 g 99mTc-labelled liver/ground beef. There was no significant difference in either the lag phase or the linear emptying phase of gastric emptying between the control and duodenal intubation groups. The emptying phase of the test meal, but not the lag phase, was slower (p less than 0.01) in the ileal intubation group than in the non-intubated and duodenal intubation groups. There were fewer (p less than 0.01) antral pressure waves in the ileal than in the duodenal intubation group. We conclude that ileal but not duodenal intubation has an important inhibitory influence on gastric emptying and antral motility.

Pattern of gastric emptying in the pig: Relation to feeding

The aims of the present study were to compare the gastric emptying of dry matter (DM) and liquids during the feeding period with that following meal consumption, to clarify the relationship between feeding and gastric emptying, and to investigate how gastric emptying changes in growing animals. The studies were performed in pigs fitted with a gastric cannula and fed on a normal finely ground solid diet mixed with water containing CrEDTA as liquid marker. Gastric emptying was measured using a gastric evacuation technique. It was observed that between 0.75 and 6 h after feeding the total amounts emptied increased, but the proportion of the meal emptied fell, with increase in meal size; emptying of both DM and liquids with large and small meals followed an exponential pattern. In contrast, while the animals were feeding, there was linear and rapid emptying of both DM and liquids following a very short (approximately 2 min) lag phase before emptying began. The rate of emptying increased linearly with body-weight (by 0.055 g DM/min and by 0.24 ml/min per kg body-weight over the range 58-200 kg) such that the emptying of digestible energy per kg metabolic body-weight (W0.75) was roughly maintained (between 2.9 and 3.2 kJ/min per kg W0.75). This suggests that the rate of emptying may be linked in some way with the metabolic requirements of the body. The biphasic pattern of gastric emptying observed is probably the intrinsic pattern of emptying of a meal which does not require breakdown of particles before emptying can occur.

α-Amylase (EC 3.2.1.1) susceptibility rather than viscosity or gastric emptying rate controls plasma responses to starch in healthy humans

The relationship between starch alpha-amylase (EC 3.2.1.1) susceptibility, plasma responses and gastric emptying rates has been investigated in humans. Nine randomly chosen healthy subjects were given three carbohydrate test meals (25 g starch or equivalent glucose units): two maize starch pastes with (a) 240 (S24) or (b) 500 (S50) g amylose/kg, and a glucose solution (GS). At 30 min, in vitro starch alpha-amylolysis was 48 (SD 4)% for S24 and 35 (SD 4)% for S50. Test meals differed in viscosity (mPa x s: S24, 54,000; S50, 190; GS, 4). Carbohydrates were labelled with 99mTechnetium and isotope gastric emptying was measured by external gamma counting. Carbohydrate isotopic gastric emptying patterns were exponential. Half gastric emptying time (min) was significantly (P less than 0.05) shorter for S50 (19(SD 2] than for GS (26(SD 2] or S24 (29(SD 2]. No correlation was found between half gastric emptying time and plasma response values. Values for peak insulin (pmol/l) above fasting were significantly (P less than 0.05) different: GS, 306 (SD 11); S24, 227 (SD 11); S50, 187 (SD 11). It is concluded that alpha-amylase susceptibility of the test carbohydrates is a determining factor in the insulin response of healthy subjects, while viscosity of the test meals and gastric emptying rate have no effect.

Relationships between gastric emptying of solid and caloric liquid meals and alcohol absorption.

The effects of three variations in meal composition (a solid and a liquid meal consumed together, a liquid meal consumed alone, and a liquid meal consumed 90 min after a solid meal) on the rates and patterns of solid and liquid gastric emptying were examined in 13 volunteers. By including alcohol (0.5 g/kg body wt) in the liquid meal, the relationship between alcohol absorption and gastric emptying was also assessed. The lag phase and the initial emptying phase of the solid meal were prolonged (P less than 0.001) when the liquid meal was consumed with the solid meal, compared with when the liquid meal was consumed 90 min after the solid meal. In this latter situation, consumption of the liquid meal caused the cessation of emptying of solid food, and this second lag phase was followed by a slower (P less than 0.001) than initial emptying phase. Gastric emptying of the liquid meal was slower (P less than 0.005) when solid food was present and was slowest (P less than 0.05) when liquid was consumed 90 min after the solid meal. Alcohol absorption was fastest (P less than 0.05) when the liquid meal was consumed alone and slower (P less than 0.01) when alcohol was consumed with or after the solid meal. For all three meals there was a close correlation (r greater than or equal to 0.91; P less than 0.001) between alcohol absorption and liquid emptying. We conclude that gastric emptying of liquid may be influenced by solid food and that the rate and pattern of solid emptying may be modified by the presence of liquid.(ABSTRACT TRUNCATED AT 250 WORDS)

Pyloroplasty does not disrupt liquid phase gastric emptying or CCK-induced satiety

To assess the hypothesis that cholecystokinin (CCK) induces satiety by constricting the pylorus and inhibiting the rate of gastric emptying, we impaired pyloric function in 8 experimental animals using a Heincke-Mikulicz pyloroplasty procedure. Liquid phase gastric emptying was measured with a double-sampling procedure. We found that pyloroplasty did not disrupt the pattern of gastric emptying of saline or nutrient under control conditions. CCK also slowed emptying in both pyloroplasty and control animals. Finally, pyloroplasty did not affect the ability of CCK to induce satiety. We provide functional and morphological evidence that the pyloroplasty procedure successfully impaired constriction of the pyloric sphincter. These findings suggest that the pylorus is not critical to the control of liquid phase emptying and, together with the absence of a pyloroplasty effect on CCK-induced satiety, seriously question the adequacy of the pyloric mediation hypothesis.

Mechanisms governing the biphasic pattern of gastric emptying after truncal vagotomy and pyloroplasty.

The pattern of gastric emptying after truncal vagotomy and drainage is usually biphasic. An early rapid phase is followed by a characteristically abrupt transition to slow emptying. The mechanisms responsible for this pattern were studied in six dogs with truncal vagotomy and pyloroplasty, fitted with a proximal duodenal cannula. Gastric emptying was measured using gamma camera imaging of a radiolabelled 15% dextrose test meal. Sixty one hour studies were done using five designs. (1) With the cannula closed gastric emptying was initially rapid, followed by stasis (emptying at 15 min - 32% (5.3), 60 min - 34% (4.8); mean (SE)). (2) With the cannula open emptying was very rapid (15 min - 76% (4.2) p less than 0.001, 60 min - 88% (2.6) p less than 0.001 ANOVA). (3) Distal duodenal instillation of isotonic saline, at a rate equivalent to gastric emptying with the cannula closed, did not retard this rapid emptying (15 min - 78% (10.6), 60 min - 90% (5.4)). (4) With duodenal instillation of 15% dextrose, gastric emptying remained faster than in studies without diversion (15 min - 50% (7.0) NS, 60 min - 65% (6.8) p less than 0.01), but was slower than during diversion alone (p less than 0.05). (5) Finally, duodenal instillation of 15% dextrose before administration of the test meal produced slower initial emptying without subsequent stasis (15 min - 24% (4.5), 60 min - 47% (10.6)), although the amounts emptied were not significantly different from those with the cannula closed. These results indicate that after truncal vagotomy and pyloroplasty small bowel resistances play a significant role in controlling gastric emptying. Osmoreceptor responses persist after truncal vagotomy, but sympathetic inhibitory responses to small bowel distension are not involved in the regulatory process.

Dumping in Infancy Diagnosed by Radionuclide Gastric Emptying Technique

Summary:Two infants were diagnosed with dumping syndrome by a radionuclide gastric emptying method. Both patients presented with anorexia, weight loss, agitation and diaphoresis following bolus feeding by gastrostomy tube. One had documented hyperglycemia and glycosuria. Symptoms and signs of dumping in one patient were due to a gastrostomy placed in the antrum, whereby bolus tube feedings were inadvertently introduced directly into the duodenum. The second patient developed dumping symptoms after a Waterston colonie interposition was performed to correct a long gap esophageal atresia. Gastric emptying, measured by administering 99mTc‐sulfur colloid‐labeled formula, demonstrated an initial extremely rapid appearance of isotope in the small intestine, with greater than one‐third of the formula leaving the stomach in less than 2 min. The gastric emptying pattern in both patients appeared biphasic; after the initial “dumping” phase, the remaining formula emptied slowly, with monoexponential decay kinetics.

Dumping in Infancy Diagnosed by Radionuclide Gastric Emptying Technique

Two infants were diagnosed with dumping syndrome by a radionuclide gastric emptying method. Both patients presented with anorexia, weight loss, agitation and diaphoresis following bolus feeding by gastrostomy tube. One had documented hyperglycemia and glycosuria. Symptoms and signs of dumping in one patient were due to a gastrostomy placed in the antrum, whereby bolus tube feedings were inadvertently introduced directly into the duodenum. The second patient developed dumping symptoms after a Waterston colonic interposition was performed to correct a long gap esophageal atresia. Gastric emptying, measured by administering 99mTc-sulfur colloid-labeled formula, demonstrated an initial extremely rapid appearance of isotope in the small intestine, with greater than one-third of the formula leaving the stomach in less than 2 min. The gastric emptying pattern in both patients appeared biphasic; after the initial "dumping" phase, the remaining formula emptied slowly, with monoexponential decay kinetics.

Gastric emptying in infants with gastroesophageal reflux. Measurement with a technetium-99m-labeled semisolid meal.

It is well established that liquid emptying occurs in the absence of motor activity of the stomach. In contrast, solid-phase emptying is controlled in part by antral peristalsis and is, therefore, a more precise indicator of gastric motility. We developed a semisolid, radionuclide gastric emptying test using rice cereal and technetium-99m-sulfur colloid to assess antral physiology in infants with vomiting. Computer-programmed mathematical models were used to determine the shape of a line that best fit our emptying data points. Linear, simple exponential [f = 2-(t/t1/2)], and power exponential [f = 2(t/t1/2)beta] patterns of emptying were calculated, where f is the fraction of the meal remaining in the stomach at time t, and t1/2 is the time when 50% of the meal has emptied and is a determinant of the shape of the curve. In infants with simple regurgitation (chalasia) and those with vomiting and failure to gain weight, we made statistical comparisons between gastric emptying patterns after analysis of the mean percentage of retained radionuclide at 120 min, calculated t1/2, and area under the curve. The coefficient of determination, R2, was calculated as an index of whether a curve provided goodness of fit to the data. Differences between groups of patients were statistically significant for all parameters of each mathematical model. However, higher coefficients of determination were noted in the power exponential model. The data suggest that the power exponential mathematical model provides the best analysis of the gastric emptying patterns for infants with chalasia and those with vomiting and failure to gain weight.(ABSTRACT TRUNCATED AT 250 WORDS)

Abnormal Pattern of Gastric Emptying of Liquid in Chronic Duodenal Ulcer

Gastric emptying was measured in 12 patients with chronic duodenal ulceration and compared with the results from 10 healthy volunteers. The test meal of 300 ml 15% dextrose, labelled with 99mTc-DTPA, was ingested in increments over 6 min. Gamma camera imaging proceeded over 30 min, with a 1-min frame time. A direct correction was applied for the fraction emptying into the small bowel during the ingestion period. Gastric emptying at 6 min was significantly greater in the group with duodenal ulcer (14.4 +/- 2.7% vs. 4.2 +/- 0.9%: mean +/- SEM, p less than 0.01). From this time onwards there were no significant differences in the rates of gastric emptying. These results suggest that chronic duodenal ulcer is associated with an abnormal pattern of gastric emptying of liquid, characterised by an initial rapid phase.

Effect of food consistency on gastric emptying in man.

The gastric emptying of two radiolabelled pancake meals of identical composition, but different consistency, was compared with the rates at which they could be broken down in vitro by mechanical agitation in a solution of either acid-pepsin or saline. Neither of the pancake meals were broken up within 150 minutes by mechanical agitation in a normal saline medium, but both were disrupted in the presence of acid-pepsin, the light consistency pancake being broken up more rapidly than the heavy consistency pancake (0.5 +/- 0.1 v 0.2 +/- 0.1% radioactivity appearing in the bathing medium per minute, p less than 0.01). Under normal conditions, the pattern and rate of gastric emptying of both meals was similar. Stimulating acid secretion with pentagastrin (6 micrograms/kg bodyweight sc) delayed the onset of emptying of both pancakes and tended to increase the slope of emptying. Under these conditions, the denser pancake was emptied more slowly than the lighter pancake because of an increase in the lag period. Thus the data did not confirm the hypothesis that the rate of emptying of disruptible solid food from the stomach under normal conditions of acid secretion is influenced by the ease with which it can be broken down by mechanical agitation in an acid-pepsin medium. The trend for an accelerated rate of emptying after administration of pentagastrin, however, may well be explained by the increased rate of disruption of the food in the presence of acid, but the longer lag periods are more compatible with inhibition of gastric emptying caused by free acid in the duodenum.

Gastric emptying, glucose tolerance, and insulin response after duodenojejunostomy

We investigated the impact of direct jejunal delivery of various meals on gastric empyting, glucose tolerance, and insulin response in a chronic dog model following duodenojejunostomy. Ten beagle dogs underwent duodenal transection 2 cm distal to the pylorus and end-to-side duodenojejunostomy 20 cm distal to the ligament of Treitz. Three months after operation each dog underwent gastric emptying studies using radiolabeled normal saline, 20% glucose solution, and standardized mixed solid meal. Glucose tolerance tests with plasma insulin determinations were obtained using the glucose meal. After duodenojejunostomy both the rapid exponential pattern of emptying of normal saline and the slower linear pattern of glucose emptying seen in intact dogs were preserved. The linear gastric emptying of the solid meal which was slower than gastric emptying of either of the liquid meals was also preserved. Although integrated plasma glucose levels over 2 hr were 484.8 ± 40.4 and 456.6 ± 30.4 mg · hr/dl in intact and duodenojejunostomy dogs, respectively ( P > 0.05), the initial rate of rise of plasma glucose was significantly delayed in the duodenojejunostomy dogs. But integrated plasma insulin levels over 2 hr differed significantly ( P < 0.05) between the intact (71.6 ± 9.2 μU · hr/nl) and duodenojejunostomy (48.3 ± 6.2 μU · hr/nl) dogs. We conclude that duodenojejunostomy (jejunal delivery) preserved the patterns of gastric emptying of saline, glucose, and mixed solid meals; retarded initial plasma glucose response to the glucose meal; and blunted plasma insulin response to the glucose load.

Motilin response to a glucose load aberrant in smokers.

Smoking is known to influence the blood glucose response to an oral glucose load, possibly by altering the gut motility. Because the peptide hormone motilin might be involved in the regulation of the gastric emptying pattern, we studied 12 heavy smokers and 9 non-smokers after an overnight fast and tobacco abstinence. After an oral glucose load non-smokers showed falling serum motilin levels, as expected, whereas the smokers had initially increasing values. We conclude that smoking affects the gastrointestinal tract, not only during acute nicotine exposure but also chronically.

The relationship between gastric emptying of semisolids and paracetamol absorption.

The relationship between gastric emptying rate of semisolid Tc-99m labelled Chelex-100 resin/oatmeal and paracetamol absorption was determined simultaneously in seven healthy volunteers. There was no significant correlation between the half-time of gastric emptying and the time of the peak serum paracetamol concentration. There was no significant correlation between the area under the serum paracetamol concentrations at 60 and 90 min and the % meal emptied in 60 and 90 min respectively. Three subjects showed a lag phase in gastric emptying pattern, while the other four showed the emptying curves without evidence of a delayed phase of emptying. Individual values of gastric emptying determined by the methods varied widely.

Mythical models of gastric emptying and implications for food consumption studies

Two of the most important factors governing gastric emptying are meal volume and food composition. These factors have also been demonstrated to influence the secretion of gastric acid, digestive enzymes and gut hormones in both fish and mammals. In mammals, feedback loops involving gastrointestinal hormones have been implicated in the control of gastric motility and enzyme secretion. These findings are briefly reviewed and it is demonstrated how the functioning of the feedback loops could lead to changes in gastric emptying patterns. A simulation exercise was carried out incorporating these physiological observations into the emptying model. The results predicted that an exponential function would best describe the emptying of small, easily digested low energy food particles from the stomach, but that a linear expression would give a better fit to the emptying data when food consisted of high energy large sized particles. These predictions were supported by results obtained in a number of experimental studies. These results are discussed in terms of selecting methods for the estimation of daily food consumption of fish species.

Studies on the motor function of canine gastric tube

The need for a drainage procedure to facilitate emptying of the gastric tube remains a controversial issue. Then to elucidate whether we need a drainage procedure or not, on both gastric tube without drainage and with drainage, the author investigated the electromyographical changes of antrum and the manometric changes of pyloric portion before and after expansive stimulation, and observed the emptying of gastric tube. The results are summarized as follows: 1. In the gastric tube without drainage procedure, the prolongation of discharge intervals and the acceleration of propagation velocity were noted electromyographically, and the increase of pressure of pyloric portion was noted. When expansive stimulation was added, these findings were more enhanced. 2. In the gastric tube with pyloromyotomy, the states of electromyographical and manometrical excitation were weakened as compared with the gastric tube without drainage, and the reaction to expansive stimulation was also decreased. 3. By addition of pyloromyotomy, the emptying of gastric tube was more accelerated and the pattern of gastric emptying became nearly stabilized. The above results suggested that the gastric tube may need a drainage procedure to facilitate emptying.

Effect of proteins on availability of zinc. I. Gastrointestinal transit time of casein and whey protein and zinc absorption in weaned rats.

The availability of zinc from isolated casein (CasD) was compared with that from whey protein (WpD) in 23-25 day old rats. The study was designed to show the course of the gastrointestinal transit time of either chyme (radiolabeled by 141Ce as a non-absorbable marker) or zinc (as 65Zn) in groups of 9 to 12 animals each. Animals were killed either 1/4, 1/2, 1, 2, 6, 12 or 24 hours after intragastric intubation of the protein suspensions. Immediately afterwards, intragastric pH was measured and the determination of zinc retention in intestinal tissues and liver as well as in the carcass was performed. 30 and 60 minutes after intubation the intragastric pH of the CasD group was significantly lower than that of the WpD group. The precipitation behaviour of the two protein fractions - compact curd formation by the CasD versus flocculent structure of the WpD - was determining for the pattern of gastric emptying. With the WpD the chyme was emptied according to an exponential function; while the CasD precipitate left the stomach in three distinct phases. With either protein suspension zinc left the stomach ealier than the bulk of the chyme, indicating a partial disintegration of the zinc-protein-complexes. With the WpD, zinc was emptied exponentially, whereas with the CasD a biphasic emptying pattern was found. Ileum was found to be the main zinc absorbing segment, mainly due to the long time of contact with zinc. After 2 and 12 hours zinc retention from the CasD was significantly higher than that from the WpD, however, after 24 hours retention was significantly better from the WpD. From the present study it can be concluded that, for comparison of zinc availability from diets containing different proteins, short-term experiments are not appropriate. Furthermore, it can be supposed that preabsorptive processes in the stomach are crucial for the availability of zinc.

Gastric emptying of barley-soya-bean diets in the pig: effects of feeding level, supplementary maize oil, sucrose or cellulose, and water intake.

A technique for measuring gastric emptying in growing pigs by complete removal of digesta through a gastric cannula is described. Four pigs were fitted with gastric cannulas and each was used in three trials. The effects of level of feeding (trial 1), cellulose (C), maize-oil (MO) or sucrose (SU) supplementation (trial 2) and the level of water intake (trial 3) on gastric emptying of digesta, dry matter (DM) and nitrogen from a barley-weatings-soya-bean (B) diet were measured during 4 h after the morning feed. In trial 1, pigs were given 0.66, 0.83, 1.00 or 1.17 times their standard level of feeding. As the level of feeding rose, so the weight of digesta, DM and N emptied in the first hour after feeding increased. This trend continued to some extent in the second hour, but no effects of level of feeding were seen in the third and fourth hours. In trial 2, maize-oil addition to the diet significantly reduced the gastric-emptying rate of DM in the second hour after feeding, compared with the rates for diet C. The rate of N emptying was significantly slower for diets MO and SU than for diet C. In trial 3 there were no significant effects of water intake level (1.75, 2.50 and 3.25 times the weight of diet) on the rate of DM or N emptying from the stomach. The rate of digesta (and thus of water) emptying in the first hour after feeding increased significantly as the water intake rose. It was concluded that because the pattern of gastric emptying was very similar despite large differences in nutritional inputs, an important property of the process appeared to be resilience.