Gastric Emptying Of Liquids Research Articles

Influences of fat restriction and lipase inhibition on gastric emptying in obesity

Accelerated gastric emptying of solids may play a role in the pathogenesis of obesity. Orlistat, a potent lipase inhibitor, induces fat malabsorption and body weight loss but might accelerate gastric emptying as a result of suppressed CCK release. The aim was to investigate the role of fat restriction and lipase inhibition in CCK release and gastric emptying. A total of 28 patients (three male (M)/25 female (F); mean (s.d.) BMI 37.4(3.9) kg/m2) entering a randomized, double-blind, placebo-controlled study. CCK release and gastric emptying by scintigraphy at the start (T0), after 1 month of an energy- and fat-restricted diet and placebo (T1), and after 1 month (T2) and 1 year (T3) of randomization to placebo or 120 mg orlistat three times a day. One month of dieting and a weight loss of 2.3 kg (2.1% of initial weight) did not affect gastric emptying of liquids and solids. Basal and meal-stimulated CCK levels remained unaltered. Placebo-treated subjects who continued the diet for 1 month demonstrated a borderline significant suppressed CCK secretion and a weight loss of 1.2 kg (1.0%) without an effect on gastric emptying. After 1 year, the CCK secretion recovered to or beyond values at the start. A significantly slower emptying of solids (17.6 (T3) versus 25.9 (T1)%/h) and a weight loss of 10.4 kg (9.9%) was observed. Subjects on 120 mg orlistat lost 2.5 kg (2.5%) after 1 month, and 9.8 kg (9.9%) after 1 year. Basal and postprandial CCK release decreased significantly after the first month of orlistat treatment but normalized after 1 year. Diet and lipase inhibition did not have any influence on gastric emptying. Energy and fat restriction of 1 month did not alter gastric emptying in the whole group. Continuation of the diet for 1 year resulted in a delayed gastric emptying of solids. Lipase inhibition did not result in a sustained depressed CCK release and the anticipated acceleration of gastric emptying did not occur.

Acute effects of C-peptide on gastric emptying in longstanding type 1 diabetes

Gastric emptying (GE) of a solid (100 g beef) and liquid (150 ml 10 % dextrose) meal was measured in eight patients with type 1 diabetes during intravenous infusion of C-peptide (6 pmol/kg/ min) or isotonic saline. C-peptide had no effect on either solid or liquid GE.

Association of the Predominant Symptom With Clinical Characteristics and Pathophysiological Mechanisms in Functional Dyspepsia

Functional dyspepsia (FD) is considered a heterogeneous disorder with different pathophysiological mechanisms contributing to the symptom pattern. The Rome II committee proposed that subdividing patients with FD into groups with predominant pain versus discomfort might identify subgroups with homogeneous pathophysiological and clinical properties. The aim of this study was to analyze the relationship of predominant pain or discomfort with pathophysiological mechanisms and to evaluate whether considering individual predominant symptoms yields better results. Consecutive FD patients (n = 720; 489 women; mean age, 41.3 +/- 0.6 years) filled out a dyspepsia questionnaire and identified a single most bothersome symptom. We analyzed the association of this predominant symptom with demographic, clinical, and pathophysiological features (Helicobacter pylori status, gastric emptying in 592 patients, and gastric sensitivity and accommodation testing in 332 patients). According to Rome II criteria, 22% were pain predominant and 78% discomfort predominant. Patients with predominant pain had a higher prevalence of hypersensitivity (44% vs 25%) and delayed gastric emptying was observed less frequently in these patients (16% vs 26%), but there was major overlap. Detailed analysis showed that any of 8 dyspeptic symptoms could be predominant. Predominant early satiety or vomiting was associated with significantly higher prevalences of weight loss (89% and 75%, respectively) and of acute onset (61% and 60%, respectively). Impaired accommodation was found in 79% of patients with predominant early satiety. The highest prevalence of delayed emptying was found in predominant fullness (38%) and of hypersensitivity in predominant pain (44%). Subdividing FD patient groups according to the predominant symptom does not reliably identify subgroups with a homogeneous underlying pathophysiological mechanism.

Ursodeoxycholic acid improves gastrointestinal motility defects in gallstone patients

To simultaneously evaluate the presence of defects in gallbladder and gastric emptying, as well as in intestinal transit in gallstone patients (GS) and the effect of chronic ursodeoxycholic acid (UDCA) administration on these parameters and on serum bile acids and clinical outcome in GS and controls (CTR). After a standard liquid test meal, gallbla-dder and gastric emptying (by ultrasound), oroileal transit time (OITT) (by an immunoenzymatic technique) and serum bile acids (by HPLC) were evaluated before and after 3 mo of UDCA (12 mg/kg bw/d) or placebo administration in 10 symptomatic GS and 10 matched healthy CTR. OITT was longer in GS than in CTR (P < 0.0001); UDCA significantly reduced OITT in GS (P < 0.0001), but not in CTR. GS had longer gastric half-emptying time (t(1/2)) than CTR (P < 0.0044) at baseline; after UDCA, t(1/2) significantly decreased (P < 0.006) in GS but not in CTR. Placebo administration had no effect on gastric emptying and intestinal transit in both GS and CTR. The gallstone patient has simultaneous multiple impairments of gallbladder and gastric emptying, as well as of intestinal transit. UDCA administration restores these defects in GS, without any effect in CTR. These results confirm the pathogenetic role of gastrointestinal motility in gallstone disease and suggest an additional mechanism of action for UDCA in reducing bile cholesterol supersaturation.

New motilin agonists: a long and winding road

New motilin agonists: a long and winding road

Solid and liquid gastric emptying in patients with gastro-oesophageal reflux.

A dual isotope radionuclide technique has been used to assess solid and liquid gastric emptying simultaneously in 72 patients with symptomatic gastro-oesophageal reflux and 22 normal controls. Objective evidence of gastro-oesophageal reflux was obtained from standard acid reflux testing and/or endoscopy in all patients. Solid emptying was delayed in 32 patients (44 per cent), liquid emptying was delayed in 27 patients (37 per cent) and 16 of those two groups had delayed solid and liquid emptying. Thus 29 patients (40 per cent) had normal solid and liquid group (P less than 0.01). There was a significant correlation (P less than 0.01) between the solid and liquid gastric emptying values obtained in patients. No significant correlation was found between gastric emptying and the resting lower oesophageal sphincter pressure or the presence of symptoms of regurgitation and epigastric fullness. In the patients with delayed solid emptying there was a higher incidence of oesophagitis than in patients with normal emptying (P less than 0.05).

Relationship between gastric emptying of liquid and postvagotomy diarrhoea.

Gastric emptying of liquid was studied in 10 normal volunteers and in 27 patients previously treated with truncal vagotomy and drainage. Thirteen of the twenty-seven patients complained of persistent postvagotomy diarrhoea. For each study 300 ml 15 per cent dextrose, labelled with 99mTc-diethylene triamine penta-acetic acid (DTPA), was ingested at a standard rate by subjects who sat facing a gamma camera. Imaging proceeded for 30 min. Gastric area activity curves were corrected for emptying of the test meal during ingestion, and for movement using a new image alignment technique. Gastric emptying at 15 min was 10 +/- 2.6 per cent (mean +/- s.e.m.) in healthy volunteers, 48 +/- 7.3 per cent in patients without diarrhoea, and 84 +/- 2.3 per cent in those with diarrhoea (P less than 0.001, ANOVA). Gastric emptying from 15 min onwards was slower than normal in both patient groups (P less than 0.001). These results show that initial gastric emptying is rapid following truncal vagotomy and drainage, and this change is greater in patients with postvagotomy diarrhoea. No patient with diarrhoea had normal initial gastric emptying.

Gastric emptying after anterior lesser curve seromyotomy and posterior truncal vagotomy.

Anterior lesser curve seromyotomy with posterior truncal vagotomy (ASPTV) provides a simple, safe and expeditiously performed method of denervating the parietal cell mass, whilst preserving the pylorus. Dumping and diarrhoea are uncommon after this procedure. Gastric emptying has been assessed after ASPTV and other elective operations for duodenal ulcer. Liquid and solid phase gastric emptying studies were performed in control subjects (17), patients before and at least six months after ASPTV (14), vagotomy and pyloroplasty both without (8) and with (6) diarrhoea, vagotomy and gastroenterostomy (11), and Polya gastrectomy (7). There was no delay in emptying time for liquids or solids between ASPTV patients and controls. With the exception of an increase in the early emptying of liquids (P = 0.02) after ASPTV, gastric emptying was not different from normal. After truncal vagotomy and pyloroplasty in patients without diarrhoea the gastric emptying of solids, but not of liquids, was markedly increased (P = 0.00001), whereas in those with diarrhoea both liquid and solid phase emptying were markedly increased (P less than 0.001). When gastroenterostomy was used as the drainage procedure both phases of emptying were increased. After Polya gastrectomy, both early and late emptying of liquids and solids were increased (early phase P less than 0.05, overall emptying P less than 0.001).

Effect of gastric resection, Roux-en-Y diversion and vagotomy on gastric emptying in the rat.

Solid and liquid gastric emptying studies were conducted in 61 male Wistar rats. In 20 animals a two-thirds Pólya-type gastric resection was performed and 21 had a similar resection with a 10-cm Roux-en-Y diversion. In nine of the Roux diversions truncal vagotomy was also carried out. Twenty animals acted as controls: ten unoperated and ten that received laparotomy only. Body-weight and gastric emptying were measured weekly for 4 weeks and monthly for 4 months after surgery. Animals subjected to gastrectomy revealed a weight loss of approximately 16 per cent after operation. Weight gain was slower after Roux reconstruction than after Pólya-type anastomosis and slowest in animals with vagotomy and Roux drainage (P < 0.05). Gastric emptying was unchanged in unoperated controls. Animals in which a laparotomy was performed had delayed solid and liquid emptying for the first 4 weeks after operation (P < 0.05). Following Pólya-type gastrectomy, liquid emptying was delayed for 4 months. Solid emptying was unchanged, with no evidence of the delay present in animals with a laparotomy. Animals subjected to Roux-en-Y diversion showed a greater delay in liquid emptying than those with a Pólya resection; solid emptying was also delayed (P < 0.05). Severe gastric retention of liquids and solids occurred in the early postoperative phase when vagotomy was added to the Roux diversion (P < 0.01). Emptying of solids adopted a relatively normal linear pattern after this initial retention. Emptying of liquids, however, remained abnormal, appearing to adopt a biphasic pattern.

Efficiency and efficacy of multi‐channel gastric electrical stimulation

Abstract Gastric electrical stimulation (GES) using single channel has been under investigation for its therapeutic potential for gastroparesis. The aim of this study was to study the efficacy and efficiency of multi‐channel GES in accelerating gastric emptying in dogs. The study was performed in eight dogs, and gastric emptying of liquid was assessed in three randomized sessions of control, one‐channel GES and four‐channel GES. It was found that (i) GES of both one‐channel and four‐channel was able to completely entrain the slow waves in the entire stomach. However, the stimulation energy required by four‐channel GES was only 1% of that required by one‐channel GES. (ii) Four‐channel, but not one‐channel, GES significantly and substantially accelerated gastric emptying. An increase of 121.0 and 93.9% was noted with four‐channel GES at 30 and 60 min after the meal, respectively. It was concluded that four‐channel GES is substantially more efficient and effective than conventional single‐channel GES in improving gastric emptying. It is worthy to explore its therapeutic potential for gastroparesis in clinical settings.

Effect of atilmotin on gastrointestinal transit in healthy subjects: a randomized, placebo‐controlled study

We studied effects of i.v. atilmotin (BAX-ACC-1638, a novel motilin agonist, circulating t(1/2) < 10 min) on gastrointestinal transit in humans using a randomized, parallel-group, dose-response double-blind study of i.v. atilmotin, 6, 30, 60 microg or vehicle (placebo) given 2 min after standardized breakfast, lunch and dinner. The breakfast meal contained (99m)Tc-eggs and (111)In-milk. Full gastrointestinal transit was measured by scintigraphy. Primary endpoints were % gastric emptying (GE) at 30 min, GE t(1/2), colonic filling (CF) at 6 h, and geometric centre of colonic transit at 24 h. Analysis included adjustment for age, gender and body mass index, with Bonferroni correction applied for multiple comparisons. A significant treatment effect of atilmotin was detected for GE (%) at 30 min for solids and liquids (P < 0.01 for both). There were no significant effects on CF or CT and no significant adverse clinical events. Thus, atilmotin accelerates GE of solids and liquids in healthy humans. These data suggest that, at the doses tested, atilmotin should be considered for treatment of stomach motility disorders.

Effect of different types of fundoplication on the gastric emptying of liquids and gastric compliance in rats

Background/Purpose The aim of this study is to evaluate the early and late effects of partial fundoplication (PFp) and total fundoplication (TFp) on gastric emptying (GE) and on gastric compliance (GC) in rats. Methods One hundred fifty-nine male Wistar rats, 6 to 8 weeks of age and weighing 150 to 250 g underwent sham operation, PFp or TFp. They were randomly divided into early group (group E) and late group (group L), evaluated on the 7th and 28th postoperative days, respectively. Gastric emptying studies were performed with and without short-term induction of GE delay. Results Gastric emptying studies: In group E, TFp altered gastric retention when compared with sham subgroup in rats with GE delay. In group L, neither PFp nor TFp produced changes in GE. Gastric volume–gastric compliance studies: In group E, only TFp reduced significantly gastric volume, but both PFp and TFp caused a significant decrease in GC. A trend toward normalization of gastric volume and GC was perceived in group L. Partial fundoplication did not change the intragastric pressure response in either group E or group L. Total fundoplication increased the intragastric pressure significantly in group E, but this difference disappeared on the 28th postoperative day. Conclusions Partial fundoplication induces less change in gastric motor physiology than TFp. These findings provide background to explain some differences in the postoperative course after PFp and TFp.

Dyspepsia and Irritable Bowel Syndrome After a Salmonella Gastroenteritis Outbreak: One-Year Follow-up Cohort Study

It has been reported that some patients develop functional digestive disorders, particularly irritable bowel syndrome (IBS), after acute gastroenteritis (AGE). However, the presence of dyspepsia has not been specifically addressed. We prospectively evaluated development of dyspepsia and IBS during a 1-year follow-up in a cohort of adult patients affected by a Salmonella enteritidis AGE outbreak. Questionnaires were sent to 1878 potential participants at baseline and 3, 6, and 12 months; 677 had experienced a Salmonella enteritidis AGE on June 23, 2002, and 1201 had not (randomly selected controls, matched for village of residence, age, and sex). At 12 months, 271 patients and 335 controls returned the questionnaires. Data permitted the establishment of dyspepsia and IBS diagnosis by Rome II criteria. Before the AGE outbreak, the prevalence of dyspepsia was similar in cases and controls (2.5% vs 3.8%); the prevalence of IBS was also similar (2.9% vs 2.3%). At 3, 6, and 12 months, the prevalence of both dyspepsia and IBS had increased significantly in exposed compared with unexposed subjects. Overlap between dyspepsia and IBS was frequent. At 1 year, the relative risk for development of dyspepsia was 5.2 (95% confidence interval, 2.7-9.8) and for IBS was 7.8 (95% confidence interval, 3.1-19.7). Prolonged abdominal pain and vomiting during AGE were positive predictors of dyspepsia. No predictive factors for IBS were found. Salmonella gastroenteritis is a significant risk factor not only for IBS but also for dyspepsia; at 1 year of follow-up, 1 in 7 and 1 in 10 subjects developed dyspepsia or IBS, respectively.

Thirteenth International Workshop on Electrogastrography Feinberg Pavillion Northwestern University Medical Center, Chicago, Illinois May 18‐19, 2005

Gastric electrical stimulation (GES) using single channel has been under investigation for its therapeutic potential for gastroparesis. The aim of this study was to study the efficacy and efficiency of multi-channel GES in accelerating gastric emptying in dogs. The study was performed in eight dogs, and gastric emptying of liquid was assessed in three randomized sessions of control, one-channel GES and four-channel GES. It was found that (i) GES of both one-channel and four-channel was able to completely entrain the slow waves in the entire stomach. However, the stimulation energy required by four-channel GES was only 1% of that required by one-channel GES. (ii) Four-channel, but not one-channel, GES significantly and substantially accelerated gastric emptying. An increase of 121.0 and 93.9% was noted with four-channel GES at 30 and 60 min after the meal, respectively. It was concluded that four-channel GES is substantially more efficient and effective than conventional single-channel GES in improving gastric emptying. It is worthy to explore its therapeutic potential for gastroparesis in clinical settings.

Delayed gastric emptying in gastroesophageal reflux disease: the role of malrotation

The association between gastroesophageal reflux (GER) and intestinal malrotation (IM) has been well described. Delayed or impaired gastric emptying in IM is thought to be a contributing factor in the development of gastroesophageal reflux disease (GERD). The current study assessed the role of malrotation in delayed gastric emptying in children with GERD. We also evaluated the interactions between GERD, malrotation, gastric pH abnormalities, and gastric dysmotility. Sixty-seven patients between 1 and 5 years of age (mean 3.08+/-1.2) and with symptoms of GER, such as emesis, reactive or recurrent lung disease, and/or growth retardation, were studied in 2001-2005. Upper and lower gastrointestinal contrast studies were performed for the diagnosis of malrotation. Gastric motility was evaluated with a liquid gastric emptying protocol. GER was documented by upper gastrointestinal studies, scintigraphy, and/or 24-h pH monitoring. In our series of 44 children with GERD, there was an unexpectedly high incidence of IM: 54.5% (24/44). IM has previously been known to occur in 25% of patients with GERD. GERD was found in 24 (82.7%) of 29 patients with IM. Mean nuclear gastric emptying (MNGE) was 51.6+/-8.04 min in patients with isolated GERD and 96.6+/-20.5 min in children with IM and GERD. There was a statistically significant difference in MNGE time (p<0.05) between children with primary GERD and in those with GERD and IM. Esophageal pH monitoring showed that mean fraction time below pH 4 was 7.06+/-1.1% in patients with isolated GERD and 14.7+/-4.1% in patients with IM and GERD. GERD is common in children between 1 and 5 years old. Using gastric emptying studies and esophageal pH monitoring, we have shown that gastric dysmotility and esophageal pH abnormalities are highly prevalent, especially in children with malrotation compared with children with isolated GERD. These findings suggest that malrotation is an important factor responsible for delayed gastric emptying in GERD. Hence, we recommend that all infants and children with GERD and delayed gastric emptying undergo careful evaluation for malrotation.

Delay of Gastric Emptying Measured by13C-Acetate Breath Test in Neurologically Impaired Children with Gastroesophageal Reflux

Delayed gastric emptying often occurs in patients, including children, with gastroesophageal reflux (GER) due to neurological impairment (NI). The aim of this study was to evaluate gastric emptying of liquids in children with symptomatic GER using the (13)C- acetate breath test (ABT), and to compare the gastric emptying rates between children without and with NI. Thirteen patients were divided into 2 groups: group I without NI (5 patients) and group II with NI (8 patients). The liquid test meal consisted of Racoltrade mark (5 ml/kg) mixed with (13)C- acetate (50 mg for infants, 100 mg for children, and 150 mg for adolescents). Breath samples were collected for (13)CO (2) measurement before the intake of the meal, every 15 minutes during the first 2 hours after the meal and every 30 minutes thereafter to assess the ingestion of (13)C- acetate and Racoltrade mark. (13)CO (2) was measured using a gas chromatograph-isotope ratio mass spectrometer. The results were expressed as % of (13)C expired per hour and cumulative (13)C excretion over a 3-hour period. The half excretion time in (13)C- ABT(t (1/2) ex) was 1.095 hour for group I and 1.817 hour for group II (p = 0.0045). The lag time (t lag), which reflected the initial delay of gastric emptying, was 0.666 h for group I and 1.002 h for group II (p = 0.0045). Gastric emptying studies can be easily and reliably carried out in children with NI using (13)C- ABT. We showed that we were able to determine the gastric emptying rate by (13)C- ABT in patients with GER due to NI.

Reproducibility and reliability of the 13C-acetate breath test to measure gastric emptying of liquid meal in infants

Objective This study assessed the noninvasive 13C-acetate breath test ( 13C-ABT) as a reliable and reproducible method to evaluate gastric emptying in infants Methods Gastric emptying was measured simultaneously by scintigraphy and 13C-ABT in 11 infants with clinical symptoms of gastroesophageal reflux to validate the method compared with the gold standard. Gastric emptying was also measured with 13C-ABT in a separate group of 14 healthy infants on 2 consecutive days to evaluate reproducibility of the method. Half-emptying times obtained with scintigraphy and 13C-ABT were correlated with Pearson’s analysis. The variability of the half-emptying times obtained on 2 consecutive days was analyzed with paired t test and by the coefficient of variation as proposed by Bland and Altman. Results The mean emptying times obtained with scintigraphy and 13C-ABT were not different (89 ± 27 min and 70 ± 39 min, respectively, P = 0.22). Both methods correlated significantly ( r = 0.75, P < 0.05). Half-emptying times measured on 2 consecutive days with 13C-ABT were 69 ± 31 min and 68 ± 30 min, respectively (mean difference = 1.4 ± 12.4 min, P = 0.67). Intraindividual coefficient of variation was 6.3%. Conclusions This study supports the 13C-ABT method as a useful tool to evaluate gastric emptying of liquids in healthy infants and in infants with gastroesophageal reflux in the field of research and in clinical evaluations.

Gastric emptying is slow in chronic fatigue syndrome

BackgroundGastrointestinal symptoms are common in patients with Chronic Fatigue Syndrome (CFS). The objective of this study was to determine the frequency of these symptoms and explore their relationship with objective (radionuclide) studies of upper GI function.MethodsThirty-two (32) patients with CFS and 45 control subjects completed a questionnaire on upper GI symptoms, and the 32 patients underwent oesophageal clearance, and simultaneous liquid and solid gastric emptying studies using radionuclide techniques compared with historical controls.ResultsThe questionnaires showed a significant difference in gastric (p > 0.01) symptoms and swallowing difficulty. Nocturnal diarrhoea was a significant symptom not previously reported.5/32 CFS subjects showed slightly delayed oesophageal clearance, but overall there was no significant difference from the control subjects, nor correlation of oesophageal clearance with symptoms. 23/32 patients showed a delay in liquid gastric emptying, and 12/32 a delay in solid gastric emptying with the delay significantly correlated with the mean symptom score (for each p ≪ 0.001).ConclusionsGI symptoms in patients with chronic fatigue syndrome are associated with objective changes of upper GI motility.

Gastric scintigraphy with a liquid–solid radiolabelled meal: performances of solid and liquid parameters

To assess the clinical performance of parameters of liquid-solid gastric emptying (GE) scintigraphy. Fifty-three controls and 476 patients underwent GE scintigraphy using a liquid-solid test meal (non-ulcer dyspepsia, n=180; gastro-oesophageal reflux disease, n=123; dyspepsia after anti-reflux surgery, n=29; diabetes mellitus, n=96; cystic fibrosis prior to heart-lung transplantation, n=48). Time-activity curves were fitted by a power exponential function and half-emptying times (T1/2) were computed. The lag phase (Tlag) and constant emptying (TRE) times of solid emptying were also calculated using a mathematical method (maximum slope tangent method). TRE and T1/2 of solids were higher in each subgroup of patients vs. controls (P=0.0001) and in cystic fibrosis patients vs. gastro-oesophageal reflux patients (P=0.0001). Tlag was significantly higher only in non-ulcer dyspepsia patients vs. controls (P=0.001). There was no significant difference for liquid parameters. Using the mean+/-1.96 SD of the solid and liquid T1/2 values obtained in controls, GE was normal (n=251; 53%), delayed (n=183; 38%), accelerated (n=33; 7%) or mixed (n=9; 2%). Delayed solid T1/2 was the most prominent alteration (n=189), and alterations of liquid GE alone were present in only 24 (5%) patients. A good correlation was found between solid T1/2 and TRE (r=0.88), but no correlation between Tlag and TRE, suggesting that these estimates represent independent phases of GE. In 26 patients, all GE parameters of solids and liquids were normal except Tlag (n=8) or TRE (n=18). The lack of significant differences between the different patient subgroups did not allow emptying profiles to be drawn according to patient pathology. Liquid GE scintigraphy provided poor and unreliable information in terms of patient discrimination and the drawing of pathophysiological profiles of abnormal GE. Tlag and TRE may confirm GE alteration, especially when solid T1/2 values are at the superior limit of normality, and may improve the performance of GE scintigraphy, rather than using liquid parameters.

Influence of sildenafil on gastric sensorimotor function in humans

After a meal, the proximal stomach relaxes probably through the activation of nitrergic neurons in the gastric wall. Nitric oxide-induced smooth muscle relaxation involves activation of soluble guanylate cyclase, with cGMP production, which is then degradated by phosphodiesterase-5 (PDE-5). The aim of this study was to investigate the effect of sildenafil, a selective PDE-5 inhibitor, on fasting and postprandial proximal gastric volume and on gastric emptying rates in humans. A gastric barostat was used to study gastric compliance and perception to isobaric distension in healthy subjects before and after placebo (n = 13) or sildenafil, 50 mg (n = 15). In 10 healthy subjects, two gastric barostat studies were performed in randomized order to study the effect of placebo or sildenafil on postprandial gastric relaxation. Similarly, solid and liquid gastric emptying rates were studied in 12 healthy subjects. Sildenafil significantly increased fasting intragastric volume (141 +/- 15 vs. 163 +/- 15 ml, P < 0.05) and volumes of first perception. Sildenafil induced a higher and prolonged gastric relaxation either at 30 min (357 +/- 38 vs. 253 +/- 42 ml, P < 0.05) or 60 min (348 +/- 49 vs. 247 +/- 38 ml, P < 0.05) after the meal. Sildenafil did not alter solid half-emptying time but significantly delayed liquid emptying (43 +/- 4 vs. 56 +/- 4 min, P < 0.01). In conclusion, sildenafil significantly increases postprandial gastric volume and slows liquid emptying rate, confirming that meal-induced accommodation in humans involves the activation of a nitrergic pathway. The effect of sildenafil on gastric fundus suggests a therapeutic potential for phosphodiesterase inhibitors in patients with impaired gastric accommodation.