Role of the Antrum in the Gastric Emptying of a Non-Nutrient Liquid in the Rat

Forty male Wistar rats underwent liquid gastric emptying analysis with a non-nutrient liquid–^99mTC-tin colloid in physiologic saline. Twenty then had two-thirds resection of the glandular stomach with Billroth-Il-type reconstruction. Twenty served as controls: 10 unoperated and 10 with a laparotomy alone. Emptying was studied weekly for 4 weeks, then monthly for 4 months. Emptying was unchanged in unoperated controls. Laparotomy alone caused delayed emptying for 2 months (p < 0.05). After Billroth-II resection emptying was delayed for 4 months (p < 0.01). This delay included both the early and late phases of gastric emptying. We conclude that a laparotomy alone delays gastric emptying. The addition of an antrectomy causes a greater emptying delay, which persists for longer than that due to laparotomy alone. Thus, in a situation in which the small bowel and gastric feedback mechanisms are inoperative, the antrum is seen to play an important role in the gastric emptying of liquids. This supports the concept in man that antral contractions arc important in ensuring the normal active emptying of liquids from the stomach.     

The importance of the pylorus as a regulator of solid and liquid emptying from the stomach

The role of the pylorus in the control of gastric emptying of liquids and digestible solids was investigated in the present study by pylorus excision in six pigs. The pylorus was left intact in another six pigs. Antro-pyloro-duodenal motility was recorded by a sleeve sensor and side holes. Liquid emptying was significantly more rapid in pylorus excised than in pylorus intact animals, during intraduodenal infusion of isosmolar dextrose (712 mL vs 107 mL), fatty acid (402 mL vs 46 mL), amino acids (752 mL vs 112 mL), 25% dextrose (392 mL vs 51 mL) and 3 normal saline (705 mL vs 157 mL). In pylorus excised animals, in contrast to pylorus intact animals, the manometric pattern of isolated pyloric pressure waves at the distal stomach was rarely seen (P < 0.05). In a second series of experiments, pylorus excised animals emptied significantly more (P < 0.04) meat over 120 min (181 g) than pylorus intact animals (80 g), but the proportion of particle sizes emptied was unaltered. In the pig, localized pyloric contractions are important for retardation of gastric emptying when nutrient or hyperosmolar solutions enter the duodenum. By contrast, the pylorus is unimportant in determining the size of solid particles emptied from the stomach.     

Stereospecific Effects of Intraduodenal Tryptophan on Pyloric and Duodenal Motility in Humans

Edelbroek M, Sun W-M, Horowitz M, Dent J, Smout A, Akkermans L. Stereospecific effects of intraduodenal tryptophan on pyloric and duodenal motility in humans. Scand J Gastroenterol 1994;29: 1088-1095.

Background: L-Tryptophan delays gastric emptying in animals to a greater extent than D-tryptophan, but none of the possible motor mechanisms responsible for this stereospecific effect have been evaluated.

Methods: In 11 healthy volunteers antropyloroduodenal pressures were recorded in the fasted state with a sleeve/sidehole manometric assembly during 20-min intraduodenal infusions (2 ml-min^]) of isotonic L- AND D-tryptophan (50 mM, pH 5.7) and normal saline (pH 5.5), given in randomized order.

Results: Intraduodenal L-tryptophan increased basal pyloric pressure (p < 0.05), whereas D-tryptophan had no effect. In contrast, l- and D-tryptophan both stimulated (p < 0.05) localized phasic pyloric pressure waves, and there was no significant difference in the responses. The number of duodenal pressure waves was greater during infusion of L-tryptophan than during D-tryptophan (p<0.05).

Conclusion: We conclude that intraduodenal tryptophan has stereospecific effects on pyloric and duodenal motility. Although the precise contribution of these differential effects to gastric emptying remains to be clarified, they may be partialK responsible for the differences in gastric emptying of D-tryptophan and L-tryptophan.     

Effect of altering gastric emptying on postprandial plasma glucose concentrations following a physiologic meal in type-II diabetic patients

The purpose of this study was to determine the effects of altering gastric emptying on postprandial plasma glucose concentration after a physiologic meal in patients with type II diabetes mellitus (T II DM). Nine T II DM patients underwent a double-blind, randomized, three-way crossover study, receiving erythromycin 200 mg, morphine 8 mg, or normal saline (placebo) intravenously prior to ingestion of a radiolabeled, dual-isotope, solid–liquid meal. Gastric emptying of solids and liquids and serial plasma glucose, glucagon, and serum insulin concentrations were measured at baseline and for 5 hr after meal ingestion. Erythromycin accelerated and morphine delayed solid- and liquid-phase gastric emptying compared to placebo (P < 0.05). During the first hour, the postprandial plasma glucose concentrations were higher after erythromycin (P < 0.05) and lower after morphine (P < 0.05) compared to placebo. The peak postprandial plasma glucose concentration was higher after erythromycin (P = 0.05) and lower after morphine (P < 0.05) compared to placebo. In conclusion, pharmacologic acceleration of gastric emptying resulted in higher postprandial glucose concentrations, while delaying gastric emptying resulted in lower postprandial glucose concentrations after a physiologic meal in T II DM. These results suggest that administration of opiate analgesics or prokinetic agents to diabetic patients may alter glucose control. Modifying gastric emptying may be helpful in achieving glucose control in T II DM.     

Effect of erythromycin on gastric emptying in healthy individuals assessed by radio-opaque markers and plasma acetaminophen levels

We simultaneously recorded gastric emptying of radio-opaque markers (ROMs) and monitored serial changes in plasma acetaminophen (AAP) levels to demonstrate the relationship between the ROM and the AAP methods, and we investigated the effect of a single intravenous dose of erythromycin (EM) on gastric emptying in healthy human subjects. After an overnight fast, subjects were randomized to receive either placebo or EM lactobionate (Abbott, North Chicago, IL, USA) 250 mg intravenously in a single dose, given immediately before a standard meal. Subjects ingested 1.5 g of AAP and ROMs with the test meal. A supine plain abdominal radiograph was taken 1, 2, 3, and 6h after ingestion of the test meal. Peripheral blood samples were obtained 0, 0.5, 1, 1,5, 2, 3, and 6 h after ingestion of the test meal. EM significantly accelerated gastric emptying of ROMs. By 6 h, no markers remained in the stomach in any of the subjects in the placebo or EM groups. By 120 min, half of the ROMs had passed into the duodenum in 12.5% of subjects after placebo, whereas EM injection resulted in gastric emptying of half of the ROMs in all subjects. There was no difference in plasma AAP concentration between the placebo and EM groups. There were significant correlations between maximum plasma AAP concentration and gastric emptying of ROMs 120 min after ingestion (r=0.546;P=0.019), and between time of maximum plasma AAP concentration and gastric emptying of ROMs 120 min after ingestion (r=−0.568;P=0.014). The time taken to reach the peak concentrations ranged from 30 to 90 min after ingestion, whereas most ROMs were emptied 120 min after ingestion. We conclude that the gastric emptying assessed by ROMs and by serial changes in plasma AAP level are good, non-invasive, clinically applicable tests, with a significant correlation between the two tests. A single intravenous dose of EM had a prokinetic effect on gastric emptying, assessed by ROMs, in healthy human subjects.     

Relationship between oral glucose tolerance and gastric emptying in normal healthy subjects

Summary The relationships between gastric emptying and intragastric distribution of glucose and oral glucose tolerance were evaluated in 16 healthy volunteers. While sitting in front of a gamma camera the subjects drank 350 ml water containing 75 g glucose and 20 MBq ^99mTc-sulphur colloid. Venous blood samples for measurement of plasma glucose, insulin and gastric inhibitory polypeptide were obtained at — 2, 2, 5, 10, 15, 30, 45, 60, 75, 90, 105, 120 and 150 min. Gastric emptying approximated a linear pattern after a short lag phase (3.3±0.8 min). The 50% emptying time was inversely related to the proximal stomach 50% emptying time (r=–0.55, p<0.05) and directly related to the retention in the distal stomach at 120 min (r=0.72, p<0.01). Peak plasma glucose was related to the amount emptied at 5 min (r=0.58, p<0.05) and the area under the blood glucose curve between 0 and 30 min was related to the amount emptied at 30 min (r=0.58, p<0.05). In contrast, plasma glucose at 120 min was inversely related to gastric emptying (r=–0.56, p<0.05) and plasma insulin at 30 min (r=–0.53, p<0.05). Plasma insulin at 120 min was inversely related (r=–0.65, p<0.01) to gastric emptying. The increase in plasma gastric inhibitory polypeptide at 5 min was related directly to gastric emptying (r=0.53, p<0.05). These results indicate in normal subjects that (i) gastric emptying accounts for about 34 % of the variance in peak plasma glucose after a 75-g oral glucose load (ii) plasma glucose levels at 120 min are inversely, rather than directly, related to gastric emptying (iii) the distal stomach influences gastric emptying of glucose.     

Gastric emptying after vagotomy and pyloroplasty

Emptying of liquids from the stomach was studied in 19 patients who had had a vagotomy and pyloroplasty and the results compared with 12 patients with duodenal ulcers and 9 patients with normal upper gastrointestinal tracts. The patterns of gastric emptying after vagotomy and pyloroplasty was found to consist of a very rapid initial emptying phase followed by emptying at a rate rather faster than in the other two groups. There was no difference in the gastric emptying of patients with duodenal ulcer and those with a normal gastrointestinal tract. Patients who complained of postprandial fullness and dumping after vagotomy and pyloroplasty had extremely rapid initial gastric emptying, more than half the test solution leaving the stomach almost immediately. Three patients who had postoperative gastric ulcers, 2 patients with vomiting since operation and 1 with postvagotomy persistent diarrhea showed a starting index and half-life similar to those of asymptomatic postoperative patients and only minor differences in the emptying time.Serial tests at varying intervals during the weeks after operation showed the gastric emptying of liquids was faster than normal from the earliest postoperative test. Over the succeeding weeks, emptying became still faster and probably reached a static state in 2 or 3 months.Supported by the South African Council for Scientific and Industrial Research and the Medical Research Council of South Africa, the Ben May Gastroenterology Research Fund and the Herman Staff Research Fund.The authors would like to thank Dr. J. G. Burger, Medical Superintendent, for permission to publish.     

Motor and sensory function of the proximal stomach in reflux disease and after laparoscopic Nissen fundoplication

OBJECTIVE: After Nissen fundoplication, dyspeptic symptoms such as fullness and early satiety develop in >30% of patients. These symptoms may result from alterations in proximal gastric motor and sensory function. METHODS: We have evaluated proximal gastric motor and sensory function using an electronic barostat in 12 patients after successful laparoscopic Nissen fundoplications (median follow-up; 12 months). Twelve age- and gender-matched patients with severe gastroesophageal reflux disease (GERD) and 12 healthy volunteers served as controls. Studies were performed in the fasting state and after meal ingestion. Gastric emptying tests were performed in all patients. Vagus nerve integrity was measured by the response of pancreatic polypeptide (PP) to insulin hypoglycemia. RESULTS: Minimal distending pressure and proximal gastric compliance were not significantly different between post-Nissen patients, GERD patients, and healthy controls. Postprandial relaxation of the stomach, however, was significantly (p < 0.05) reduced post-Nissen (267 +/- 34 ml), compared with controls (400 +/- 30 ml) and GERD (448 +/- 30 ml). Postprandial relaxation was significantly (p < 0.01) prolonged in GERD patients. Postprandial relaxation of the stomach correlated with gastric emptying of solids (r = 0.62; p = 0.01). Gastric emptying of solids became significantly (p < 0.05) faster after fundoplication. Postprandial fullness was significantly (p < 0.05) increased in the operated patients. CONCLUSIONS: Post-Nissen patients have a significantly reduced postprandial gastric relaxation and significantly accelerated gastric emptying, which may explain postoperative dyspeptic symptoms. The abnormalities result from fundoplication and not from vagus nerve injury or reflux per se, because in reflux patients gastric relaxation and gastric emptying are prolonged.     

Cisapride in treatment of roux-en-Y syndrome

After Roux-en-Y gastrojejunostomy patients frequently complain of upper abdominal pain, fullness, nausea, and vomiting. This Roux-en-Y syndrome is caused by slow gastric emptying, Roux-limb stasis, or both. Treatment of this syndrome is cumbersome. We evaluated the effect of cisapride on complaints and on transit through gastric remnant and Roux limb in 24 such patients. Thirteen of them had slow gastric emptying and 13 had stasis in the Roux limb (two patients had both). Symptoms and transit were evaluated before and after three weeks of treatment using a questionnaire and scintigraphy. Responding subjects continued therapy and were interviewed again after six months. Seven patients with slow gastric emptying and three patients with Roux-limb stasis had enduring symptomatic relief; all exhibited accelerated transit during therapy: mean half gastric emptying time in the seven patients with slow gastric emptying was 204±89 min before and 111±59 min during cisapride (P<0.05); mean percentage of radioactivity, emptied from the gastric remnant, which remained in the Roux limb at 60 min in the three patients with Roux limb stasis was 74±4% before and 25±10% during cisapride (P<0.05). In patients without symptomatic response, transit did not improve. Conclusion: with cisapride long-lasting symptomatic relief and improved transit is achieved in about 40% of patients with the Roux-en-Y syndrome.This work was supported by the Jan Kornelis de Cock-Stichting. Cisapride was provided by Janssen Pharmaceutica B.V., Tilburg, The Netherlands.     

Comparison of oral and gastric administration of sucrose and maltose on gastric emptying rate and appetite.

OBJECTIVES: To investigate mechanisms by which specific sugars affect feeding behaviour. DESIGN: In an initial study, gastric emptying rate and appetite were measured following ingestion of lemon flavoured solutions of sucrose, maltose (2160 kJ, 575 ml) and water control (67 kJ, 575 ml) given in randomised order on separate days to six male volunteers. In a second study, the effects of intragastric infusions of sucrose and maltose on appetite and gastric emptying were compared in six male volunteers. RESULTS: When given orally, both the sucrose and maltose solutions slowed gastric emptying compared with water, however sucrose emptied at a faster rate than maltose. The sucrose preload increased fullness and decreased prospective consumption during the following 3 h compared with maltose and water. When administered intragastrically, the gastric emptying rate of sucrose was again faster than that of maltose but there was no difference in ratings of hunger, fullness or prospective consumption for 3 h following the infusions. CONCLUSIONS: These results show that gastric emptying of sucrose is faster than that of maltose and suggest that gastric emptying rate and hence period of gastric distension is not the predominant factor regulating appetite by these sugars. The differences observed between oral and gastric delivery suggest that oro-sensory and cognitive factors, possibly stimulated by the sweetness of sucrose, were involved in the induction of satiety.     

Role of the antrum in the gastric emptying of a non-nutrient liquid in the rat.

Forty male Wistar rats underwent liquid gastric emptying analysis with a non-nutrient liquid--99mTC-tin colloid in physiologic saline. Twenty then had two-thirds resection of the glandular stomach with Billroth-II-type reconstruction. Twenty served as controls: 10 unoperated and 10 with a laparotomy alone. Emptying was studied weekly for 4 weeks, then monthly for 4 months. Emptying was unchanged in unoperated controls. Laparotomy alone caused delayed emptying for 2 months (p less than 0.05). After Billroth-II resection emptying was delayed for 4 months (p less than 0.01). This delay included both the early and late phases of gastric emptying. We conclude that a laparotomy alone delays gastric emptying. The addition of an antrectomy causes a greater emptying delay, which persists for longer than that due to laparotomy alone. Thus, in a situation in which the small bowel and gastric feedback mechanisms are inoperative, the antrum is seen to play an important role in the gastric emptying of liquids. This supports the concept in man that antral contractions are important in ensuring the normal active emptying of liquids from the stomach.     

Gastric and oesophageal emptying in patients with Type 2 (non-insulin-dependent) diabetes mellitus

Summary Gastric emptying of a digestible solid and liquid meal and oesophageal emptying of a solid bolus were measured with scintigraphic techniques in 20 randomly selected Type 2 (non-insulin-dependent) diabetic patients receiving oral hypoglycaemic therapy and 20 control subjects. In the diabetic patients, the relationships between oesophageal emptying, gastric emptying, gastrointestinal symptoms, autonomic nerve function and glycaemic control were examined. The percentage of the solid meal remaining in the stomach at 100 min (p<0.001), the 50% gastric emptying time for the liquid meal (p<0.05) and oesophageal emptying (p<0.05) were slower in the diabetic patients compared to the control subjects. Scores for upper gastrointestinal symptoms and autonomic nerve dysfunction did not correlate significantly (p>0.05) with oesophageal, or gastric emptying. The 50% gastric emptying time for the liquid meal was positively related (r=0.58, p<0.01) to the plasma glucose concentration at the time of the performance of the gastric emptying test and the lag period, before any solid food emptied from the stomach, was longer (p<0.05) in subjects with plasma glucose concentrations during the gastric emptying measurement greater than the median, compared to those with glucose concentrations below the median. These results indicate that delayed gastric and oesophageal emptying occur frequently in Type 2 diabetes mellitus and that delayed gastric emptying relates, at least in part, to plasma glucose concentrations.     

Impaired gastric emptying and altered intragastric meal distribution in diabetes mellitus related to autonomic neuropathy?

Previous studies in diabetic patients suggested a relationship between delayed gastric emptying and increased ingesta retention in either proximal or distal stomach, but the determinants underlying these abnormalities remained obscure. We aimed at assessing the impact of cardiovascular autonomic neuropathy, blood glucose concentration, long-term glycemic control, and other factors in 34 type I and 43 type II diabetic patients (ages 21–67 and 34–81 years, respectively). Emptying was slower (P < 0.04) in type I diabetic patients than in 20 healthy control subjects (ages 23–63 years). Patients with autonomic neuropathy (N = 45) had slower gastric emptying (P < 0.02) and retained more in the distal stomach (P < 0.0001) than patients without neuropathy (N = 32). Multiple regression analyses revealed that slow emptying and increased distal retention were significantly associated with autonomic neuropathy (P < 0.043, P < 0.0002), whereas blood glucose, glycemic control, diabetes duration, age, and other factors had no discernible influence. Thus, both slow emptying and increased distal ingesta retention seem primarily referable to autonomic neuropathy.     

Measurement and Evaluation of Gastric Emptying Using Radiopaque Barium Markers

To simplify assessment of gastric emptying, we have developed a radiopaque barium marker method. The subjects were 11 healthy volunteers, 30 patients with progressive systemic sclerosis, 16 patients with dysmotility-like dyspepsia, 7 patients with irritable bowel syndrome, and 6 patients with diabetes mellitus. We tested three types of radiopaque markers with manometry by a three-channel strain gauge transducer. The 4.5-mm ring-shaped markers with a specific gravity of 1.2 were emptied from the stomach in correlation with the number of high-amplitude (>50 mm Hg) antral contractions. The percentage of residual markers at 2 hr was significantly (P < 0.05) lower in patients with irritable bowed syndrome than in normal controls, and at 5 hr it was significantly (P < 0.05) higher in patients with systemic sclerosis with esophageal dysmotility, dysmotility-like dyspepsia, or diabetes than in normal controls. This radiopaque barium marker method may be useful as a screening test for determining whether gastric emptying is rapid or delayed.     

Slow gastric emptying induced by high fat content of meal accelerated by cisapride administered rectally

The evaluation of agents potentially accelerating gastric emptying in gastric stasis syndromes is time-consuming. Since a previous study showed that emptying is slowed after antecedent fat ingestion and intravenous cisapride abolishes this effect, we investigated whether emptying delayed by fat incorporated into a meal is reversed by cisapride and thus could serve as a model for such evaluations. Twelve healthy males received, under double-blind conditions, 30 mg cisapride rectally or placebo, and 3 hr thereafter a semisolid meal of low (9.2 g) or high (37.9 g) fat content. The sequence of combinations placebo/low-fat meal, placebo/high-fat meal, and cisapride/high-fat meal was randomized. Gastric emptying and antral motility were recorded scintigraphically. After placebo/high-fat, emptying was significantly slower (P<0.05) than after placebo/low-fat. After cisapride/high-fat, emptying was significantly faster (P<0.01) than after placebo/high-fat and similar to that after placebo/low-fat. Antral motility was little affected. The slow emptying of a high-fat meal thus seems a suitable model for the evaluation of prokinetic drug effects.     

Superior mesenteric artery blood flow and gastric emptying in humans and the differential effects of high fat and high carbohydrate meals.

This study was designed to determine if the differential effect of high fat and high carbohydrate meals on mesenteric blood flow is a result of changed gastric emptying rate. Eight healthy men were studied twice. Superior mesenteric artery blood flow (Doppler ultrasound) was measured before and after a 2.5 MJ meal (either 74% of the energy as carbohydrate or 71% as fat). Emptying of meals was followed by gamma-scintigraphy. The pattern of the superior mesenteric artery blood flow response was different after the two meals (interaction effect p < 0.001 analysis of variance), with a far more sustained response after fat. The time by which half the meal had emptied (t50) was also significantly greater after fat (p < 0.02). Superior mesenteric artery blood flow corresponding to t50 was 449 ml/min after carbohydrate and 592 ml/min after fat. There was a significant curvilinear relation between the superior mesenteric artery blood flow response and gastric emptying after carbohydrate (r2 = 0.94) and no relation at all after fat. This study confirms the finding that ingestion of meals with a high fat content slows gastric emptying compared with meals with a high carbohydrate content in healthy volunteers. A more sustained mesenteric hyperaemia was also recorded after the fat meal compared with the carbohydrate meal. The relation, however, between the volume of meal remaining in the stomach and the mesenteric response was considerably different after the two meals. Further study is required to elucidate the mechanism behind the vascular responses recorded in the mesenteric bed after food in humans.     

Impaired gastric accommodation to distension and rapid gastric emptying in patients with Chagas' disease

In order to evaluate the contribution of the myenteric plexuses to the control of gastric accommodation to distension and to the rate of gastric emptying of a saline solution in man, we have evaluated these functions in patients with Chagas' disease, which is known to be associated with extensive lesions of the myenteric plexuses. Intragastric pressure was significantly higher (P<0.05) in Chagas patients (N=15) than in normal controls (N=15) for air distension volumes of 100–700 ml. In the range 300–700 ml, the difference between the groups was approximately twofold (P<0.001). The gastric emptying rate of 500 ml 154 mM NaCl in a second group of Chagas' disease patients (N=13) was significantly faster than that of the control group (N=17) at 5 min (P<0.0005) and at 15 min (P<0.005) after the test meal, but at 25 min the volumes remaining in the stomach were not statistically significant for the two groups (P>0.10). The impairment of gastric accommodation to distension and consequent rapid gastric emptying demonstrated for chagasic patients emphasizes the role of the myenteric plexuses in gastric reservoir function in man and complements previous evidence obtained in animal studies.Research carried out with the financial help of Financiadora de Estudos e Projetos (FINEP), grant 463/CT.     

Gastroparesis of digestible and indigestible solids in patients with insulin-dependent diabetes mellitus or functional dyspepsia

Gastric emptying of a solid meal and of 10 indigestible radiopaque solids was measured with scintigraphic and radiological techniques in 50 healthy volunteers (controls), 41 patients with insulin-dependent diabetes mellitus, and 50 patients with functional dyspepsia. Gastroparesis was found in 51% of our diabetic patients and 74% of our patients with dyspepsia. The values ofT _lag,T _1/2 and the percentage of isotope remaining in the stomach at 105 min were 14.9 min, 59.4 min and 25.3% in control subjects; 21.4 min, 88.1 min, and 46.9% in diabetic patients (P<0.05 vs the control group); and 23.2 min, 114.6 min, and 58.7% in dyspeptic patients (P<0.05 vs the control group). Whereas all healthy volunteers emptied all 10 indigestible solids in less than 4 hr, only 51% and 32% of diabetics and dyspeptics, respectively, achieved this emptying time (P<0.01). Their respective values ofT _1/2 were 81 min, 212 min, and 203 min (P<0.01 for diabetics and dyspeptics vs controls). We found no correlation between the findings for gastric emptying of digestible and indigestible solids. We conclude that gastroparesis affecting digestive and interdigestive motility is present in a high percentage of diabetics and functional dyspeptics and that conscientious evaluation of gastroparesis in both groups requires studies designed specifically to characterize each type of motility.     

Evaluation of gastric emptying and motility in diabetic gastroparesis with magnetic resonance imaging: effects of cisapride

OBJECTIVE: The motor mechanisms that underlie both slow gastric emptying in diabetic gastroparesis and its acceleration by cisapride are poorly understood. We have recently shown that magnetic resonance imaging (MRI) allows concurrent evaluation of both gastric emptying and regional gastric motility. METHODS: Emptying and motility were measured in eight diabetic patients with previously demonstrated delayed gastric emptying using a rapid MRI technique during oral administration of cisapride and placebo. Studies were performed in a double blind fashion and each patient acted as his own control. Subjects were studied supine for 120 min in a 1.5 Tesla MRI scanner after ingestion of 500 ml of 10% Intralipid. Gastric emptying corrected for the volume of secretions was determined every 15 min using transaxial scans. Each transaxial scan was followed by 120 coronal scans at 1 s intervals. Coronal scans were angled to provide simultaneous imaging of the proximal and distal stomach. MRI studies were also performed in seven diabetic patients with normal emptying who served as disease controls. RESULTS: Emptying was slower in the gastroparetic patients (t(1/2): 124 +/- 10 min) compared to patients with normal emptying (81 +/- 9 min, p < 0.05). Cisapride accelerated gastric emptying (74 +/- 5 vs 124 +/- 10 min) in patients with gastroparesis. The contraction amplitudes in the proximal stomach of gastroparetic patients were increased during cisapride treatment (17.2% +/- 1.8% vs 13.2% +/- 0.6%; p < 0.02), whereas antral contraction frequency, amplitude, and velocity were unchanged. CONCLUSIONS: We conclude that cisapride-induced acceleration of liquid gastric emptying in diabetic gastroparesis does not appear to result from changes in antral contractility, but may be related to changes in proximal gastric tone or gastric outlet resistance.     

Evaluation of gallbladder function before and after gastrectomy using a double-isotope method

The motor function of the gallbladder after partial distal gastrectomy for gastric carcinoma (Billroth-I reconstruction) and its relationship to the motor function of the stomach was investigated using a double-isotope method. In this method, [^99mTc]N-54-pyridoxyl-5-methyltryptophan ([^99mTc]PMT) was utilized as a tracer for the biliary tract and [¹¹¹In]diethyl-triaminopontacetic acid ([¹¹¹In]DTPA) mixed with a liquid test meal was used as a tracer for the digestive tract. Gastric emptying half-time (GET1/2) was measured, since this was used historically as the physiologic indicator of gallbladder contractile stimulus. The volume of test meal that emptied from the stomach into the duodenum per minute (VOL/MIN) was measured, as was the gastric emptying duration (GED). A series of gallbladder emptying phenomena were analyzed using three different criteria: gallbladder emptying half-time (GBET1/2), retention rate of bile in the gallbladder (RR), and the start of gallbladder bile ejection into the duodenum after ingestion (TL: time lag). While GET1/2 was reduced (P<0.01) and VOL/MIN was increased (P<0.01) after gastrectomy, GED was shortened remarkably (P<0.01). GBET1/2 showed no significant change, RR increased (P<0.05), and TL was prolonged (P<0.01). The postoperative dysfunction of the gallbladder was caused by the short and intense stimulus on the biliary tract during the duodenal phase and by intraoperative injury to the innervation of the gallbladder. In particular, the hepatic branch of the left vagus nerve was injured during the right paracardiac lymph node dissection performed as a component of the radical gastrectomy.