Plasma Motilin Concentrations Research Articles

Effects of Chinese herbal medicine Xiangbin prescription on gastrointestinal motility.

AIMTo investigate the effects of Xiangbin prescription (XBP), a Chinese herbal concoction, on gastrointestinal motility.METHODSForty healthy volunteers were recruited for this randomized controlled trial of XBP. Antroduodenojejunal manometry was used to monitor gastrointestinal motility in these subjects. After the subjects had fasted for at least 12 h, XBP (n = 30) or placebo (n = 10) was orally administrated and gastrointestinal motility was recorded for 4 h. Plasma motilin and ghrelin were measured by enzyme-linked immunosorbent assay.RESULTSOral administration of XBP significantly increased the amplitude of duodenal contractions [19.5 (13.0-26.7) vs 16.9 (12.3-23.9), P < 0.05], jejunal contractions [18.3 (15.3-25.0) vs 15.4 (11.7-23.9), P < 0.01], and the motility index of duodenal contractions [522.0 (146.0-139.0) vs 281.0 (76.5-1006.0), P < 0.01] in phase II of the migratory motor complex (MMC), which subsequently initiated the MMC cycle [74.0 (30.0-118.0) vs 116.5 (24.0-219.0), P < 0.05], shortened the duration of phase I of the MMC [42.0 (0.0-90.0) vs 111.5 (42.0-171.0), P < 0.01], and lengthened the duration of phase II of the MMC [120 (21-240) vs 58 (16-170), P < 0.01] compared to the duration before XBP administration. There were significant differences in the amplitude of jejunal contractions [19.8 (14.0-30.0) vs 18.0 (13.0-28.5), P < 0.05], the motility index of duodenal contractions [236.0 (115.0-306.0) vs 195.0 (109.0-310.0), P < 0.05)], and jejunal contractions [214.0 (95.0-403.0) vs 178.0 (55.0-304.0), P < 0.01] in phase III of the MMC. Oral administration of XBP greatly increased plasma motilin (57.69 ± 9.03 vs 49.38 ± 8.63, P < 0.01) and ghrelin (279.20 ± 104.31 vs 238.73 ± 115.59, P < 0.01) concentrations compared to concentrations after oral administration of the placebo.CONCLUSIONXBP can stimulate duodenal and jejunal motility and increase the concentrations of plasma motilin and ghrelin. The clinical applicability of XBP in treating GDIM deserves investigation.

Efficacy and Safety of Acupuncture for the Treatment of Functional Dyspepsia: Meta-Analysis.

Functional dyspepsia (FD) is a common gastrointestinal disorder. Currently, no established optimal treatment is available. The aim of this study was to assess the efficacy of acupuncture in relieving symptoms and improving quality of life in patients with FD. PubMed, MEDLINE, Web of Science, Sino-Med, China National Knowledge Infrastructure, VIP databases, and Google Scholar engine were searched from inception through April 2014 to identify randomized controlled trials of acupuncture therapy that reported on overall FD symptoms or FD-related quality of life as a primary outcome. The Cochrane Collaboration's risk of bias tool, RevMan 5.0, and Stata 12.0 software were used for meta-analysis. Data were pooled to calculate relative risk (RRs) and 95% confidence intervals (CIs) of substantial improvement after treatment for dichotomous data and mean differences (SMDs) and 95% CIs for continuous data using random-effects models. Twenty-four English- and Chinese-language articles describing randomized, placebo-controlled, clinical trials involving 3097 patients were included. Acupuncture significantly improved FD symptoms in studies reporting outcomes using dichotomous (RR, 1.19; 95% CI, 1.12-1.27; p < 0.001) and continuous (standardized MD [SMD], -0.78; 95% CI, -1.21 to -0.35; p = 0.0004) variables. Pooled analyses showed that acupuncture improved FD-related (weighted MD [WMD], 5.97; 95% CI, 3.14-8.80; p = 0.0002) and health-related (WMD, 6.83; 95% CI, 3.02-10.65; p = 0.004) quality of life, without serious adverse events. However, acupuncture failed to increase plasma motilin concentration (SMD, 0.67; 95% CI, -0.07 to 1.42; p = 0.08). Acupuncture appears to be efficacious in relieving FD symptoms and improving quality of life.

Ghrelin and motilin levels in hyperemesis gravidarum

Ghrelin, an endogenous ligand for the growth hormone secratogogue receptor, and its receptors are found in the reproductive organs and placenta. Motilin is produced from the endocrine cells of the duodeno jejunal mucosa and considered to be a regulator of interdigestive migrating contractions. Aim of this study is to investigate ghrelin and motilin levels in patients with hyperemesis gravidarum. A total of 56 patients with singleton pregnancies in the first trimester were recruited in the study, 39 with hyperemezis gravidarum and 17 normal pregnant women. Patients with medical complications and body mass index <18 or >25 were excluded. Fasting plasma ghrelin and motilin concentrations were measured. Fasting blood glucose, liver enzymes, blood urea nitrogen, creatinin, estradiol, progesterone, human chorionic gonadotropin, and thyroid function tests were also investigated. Ghrelin levels were significantly higher in patients with hyperemesis group than the normal pregnant women (p = 0.025). Serum estradiol levels were also higher in the hyperemesis group (p = 0.001). No significant difference was observed in plasma motilin levels between the two groups. In correlation analyses, maternal ghrelin was positively correlated with estradiol (r = 0.29, p = 0.029) in the whole cohort. There are a few studies about the course of circulating ghrelin levels during human pregnancy. Ghrelin administration increases food intake through central mechanisms but its effects on appetite in relation to human pregnancy is unknown. The increased levels of ghrelin in hyperemesis gravidarum might be a compensatory mechanism to restore the energy metabolism of the pregnant women.

Effect of ginger on gastric motility and symptoms of functional dyspepsia.

To evaluate the effects of ginger on gastric motility and emptying, abdominal symptoms, and hormones that influence motility in dyspepsia. Eleven patients with functional dyspepsia were studied twice in a randomized double-blind manner. After an 8-h fast, the patients ingested three capsules that contained ginger (total 1.2 g) or placebo, followed after 1 h by 500 mL low-nutrient soup. Antral area, fundus area and diameter, and the frequency of antral contractions were measured using ultrasound at frequent intervals, and the gastric half-emptying time was calculated from the change in antral area. Gastrointestinal sensations and appetite were scored using visual analog questionnaires, and blood was taken for measurement of plasma glucagon-like peptide-1 (GLP-1), motilin and ghrelin concentrations, at intervals throughout the study. Gastric emptying was more rapid after ginger than placebo [median (range) half-emptying time 12.3 (8.5-17.0) min after ginger, 16.1 (8.3-22.6) min after placebo, P≤0.05]. There was a trend for more antral contractions (P=0.06), but fundus dimensions and gastrointestinal symptoms did not differ, nor did serum concentrations of GLP-1, motilin and ghrelin. Ginger stimulated gastric emptying and antral contractions in patients with functional dyspepsia, but had no impact on gastrointestinal symptoms or gut peptides.

Motilin concentrations in relation to gastro intestinal dysmotility in diabetes mellitus

Aim Dysmotility in the upper gastro intestinal (GI) tract are common problems in diabetics. Many peptides are involved in the regulation of the motility. The aim of this study was to examine whether plasma levels of motilin were related to dysfunction in the oesophagus and stomach in a well-defined diabetic patient group. Methods Nineteen patients with symptoms from the GI tract who had been examined with oesophageal manometry, gastric emptying scintigraphy and deep-breathing test were included. They received a fat-rich meal, after which blood samples were collected and analysed for motilin concentrations. Results Symptoms of abdominal fullness and gastro oesophageal reflux significantly associated with delayed gastric emptying, whereas no symptom correlated to oesophageal dysmotility. Plasma levels of motilin were increased after the fat-rich meal ( p = 0.000), with no difference between the groups. Abnormal manometry was characterized by aperistalsis and/or simultaneous contractions. The percentage of simultaneous contractions correlated to basic and peak motilin values ( r s = 0.898, p = 0.006 and r s = 0.842, p = 0.017, respectively). Gastric emptying did not influence motilin concentrations. Conclusion Plasma motilin concentrations vary with abnormalities of oesophageal motility in diabetics, but not with abnormalities of gastric emptying.

Effect of penehyclidine on small intestinal motility in mice and rats

Objective To investigate the effect of penehyclidine on small intestinal propulsion in mice and plasma level of motilin in rats.Methods The experiment was performed in 2 parts. In experiment Ⅰ , twenty-four healthy Kunming mice of both sexes weighing 17-22 g were randomly divided into 3 groups (n = 8 each): group control (C1), group Ⅱ received intraperitoneal (IP) atropine 0.3 mg/kg (A1) and group Ⅲ received IP penehyclidine 0.3 mg/kg (P1). Nutritional semi-solid cataplasm 0.8 ml was given into the stomach at 15 min after IP injection. The mice were killed 20 min later. The abdomen was cut open. The length of the small intestine and the distance between the pylorus and the nutritional semi-solid cataplasm in the small intestine were measured. The rate of intestinal propulsion was calculated. In experiment Ⅱ , twenty-four Wistar rats of both sexes weighing 170-220 g were randomly divided into 3 groups (n=8 each);group Ⅰ control (C2);group Ⅱ received IP atropine 2 mg/kg (A2) and groupⅢ received IP penchyclidine 2 mg/kg (P2). Blood samples were taken at 30 min after IP drug administration for determination of plasma motilin concentration (by radio-immuno-aasay). Results The rate of small intestinal propulsion was significantly lower in group A1 than in group C1. There was no significant difference in the intestinal propulsion between group C1 and P1. The plasma concentration of motilin was significantly lower in group A2 than in group C2 but there was no difference in plasma motilin concentration between group P2 and C2. The plasma concentration of motilin was significantly lower in group A2 than in group P2. Conclusion Penehyclidine has no effect on small intestine motility. Key words: Quinuclidines; Gastrointestinal motility; Intestine, small

Erythromycin lacks colon prokinetic effect in children with functional gastrointestinal disorders: a retrospective study

BackgroundMotilin, a peptide hormone has a direct excitatory effect on circular smooth muscle strips derived from the human colon. Reduced plasma motilin concentration has been reported in adults with chronic constipation. Erythromycin, a non-peptide motilin receptor agonist, induces phase 3 of the migrating motor complex (MMC) in the antro-duodenum and also reduces oro-cecal transit time. A pediatric study has reported an improvement in clinical symptoms of constipation following erythromycin administration, but the effect on colon motility in children has not been formally evaluated. We used colon manometry to study the effect of intravenous erythromycin lactobionate at 1 mg/kg on colon motiltiy in ten children.MethodsWe selected patients with normal antroduodenal and colon manometry studies that were performed simultaneously. All studies were performed for clinically indicated reasons. We quantified the effect of erythromycin on colon contraction by calculating the area under the curve (AUC).ResultsThe mean (SE of mean) AUC in the colon during the fasting, post-erythromycin and postprandial phases of the study was 2.1 mmHg/sec (0.35), 0.99 mmHg/sec (0.17) and 3.05 mmHg/sec (0.70) respectively. The AUC following erythromycin was significantly less compared to the fasting phase of the study (p < 0.01).ConclusionErythromycin lacks colon prokinetic effect in children with chronic constipation evaluated by colon manometry.

Nonsteroidal anti‐inflammatory drugs induce hypermotilinemia and disturbance of interdigestive migrating contractions in instrumented dogs

Nonsteroidal anti-inflammatory drugs (NSAIDs) induce gastric ulcers due to inhibition of prostaglandin production. Prostaglandins have an influence on physiological gastrointestinal motility, but the relationships between NSAID-induced gastric ulcer, gastrointestinal motility and motilin are unknown. Fifteen dogs were allocated randomly to three groups in which either gelatin, meloxicam or indomethacin was administered. Fecal occult blood and gastrointestinal motility were monitored continuously for 6 days. In addition, analyses of the plasma motilin concentration, gastrointestinal endoscopy and gastric emptying, and detection of motilin cells were performed. Gastrointestinal motility was disturbed in the indomethacin group, presenting as disappearance of interdigestive migrating contractions (IMCs) 3 days before gastric ulcers were detected. Delayed gastric emptying and hypermotilinemia were observed significantly more often in the indomethacin group compared with the other groups. Motilin cell-crypt/villi ratio in the indomethacin group significantly decreased in the duodenum and jejunum, compared with the other groups. No significant changes in any tests were observed in the meloxicam group, when compared with the gelatin group. These findings suggest that the disturbance of IMCs caused by hypermotilinemia, with changes in motilin cell distribution, and delayed gastric emptying induced by indomethacin may contribute to the development of gastric ulcers.

Altered Gastrointestinal and Metabolic Function in the GPR39-Obestatin Receptor–Knockout Mouse

The G-protein-coupled receptor GPR39 is a member of a family that includes the receptors for ghrelin and motilin. Recently the peptide obestatin was identified as a natural ligand for GPR39. The objective of this study was to gain insight into the biological function of the GPR39 receptor. GPR39(-/-) mice were generated and analyzed. Endogenous GPR39 expression was detected in the brain (septum-amygdala) and the gastrointestinal system (parietal cells, enterocytes, neurons, and pancreas). Gastric emptying of a solid meal (measured by the (14)C octanoic breath test) in GPR39(-/-) mice was accelerated significantly with a gastric half-emptying time of 49.5 +/- 2.2 minutes compared with 86.9 +/- 8.4 minutes in GPR39(+/+) mice. A more effective expulsion of distally located pellets (30%-75% of length) was observed in the colon of GPR39(-/-) mice. Four hours after pylorus ligation, the volume of gastric secretion was increased significantly (GPR39(-/-): 638 +/- 336 microL; GPR39(+/+): 225 +/- 170 microL), but gastric acid secretion was unchanged. The mature body weight and body fat composition of GPR39(-/-) mice was significantly higher compared with GPR39(+/+) mice, but this was not related to hyperphagia because 24-hour food intake did not differ between both genotypes. In contrast, deficiency of the GPR39 receptor led to reduced hyperphagia after fasting. The cholesterol levels were increased significantly in the GPR39(-/-) mice. Our data partially confirm and extend the described in vivo effects of obestatin and suggest that this peptide plays a functional role in the regulation of gastrointestinal and metabolic function through interaction with the GPR39 receptor.

Prokinetic therapy with erythromycin has no significant impact on blood pressure and heart rate in critically ill patients

Prokinetic therapy with erythromycin has no significant impact on blood pressure and heart rate in critically ill patients

Effects of acute hypobaric hypoxia on gastric emptying and intestinal propulsion: experiment with rats

To investigate the impact of acute hypobaric hypoxia on the gastrointestinal motility. Eighty Wistar rats were randomly divided into 4 equal groups to be fed with (99)Tc(m)-labeled test food: ground level control group, put in the hypobaric chamber for 30 minutes; 3000 m simulated altitude group, exposed to the environment of simulated altitude of 3000 m for 30 minutes; 5000 m simulated altitude group, exposed to the environment of simulated altitude of 5000 m for 30 minutes; and mosapride + 5000 m simulated altitude group, fed with mosapride 2 mg/kg by perfusing stomach and fed with isotope-labeled test food 30 minutes later, and then exposed to 5000 m simulated altitude for 30 minutes. By the end of experiment the rats were killed, their stomachs were taken out to calculate the gastric emptying rate. Their intestine from pylorus to ileocecum was taken out to measure the intestinal propulsion function by using charcoal particle method. At the beginning and at the end of experiment abdominal arterial blood samples were collected to detect the plasma motilin and nitric oxide (NO) concentrations. The gastric emptying rate of the 5000 m simulated altitude group was 41% +/- 10%, significantly lower than that of the ground level group (62% +/- 12%, P < 0.01), and the charcoal transit rate of the 5000 m simulated altitude group was 37% +/- 8%, significantly lower than that of the ground level group (61% +/- 13%, P < 0.01). The gastric emptying rate and intestine propulsion rate of the 3000 m simulated altitude group were not significantly different from those of the ground level group. The gastric emptying rate of the mosapride + 5000 m simulated altitude group was 55% +/- 12%, significantly higher than that of the 5000 m simulated altitude group (P < 0.05), however, the intestine propulsion rate of the mosapride + 5000 m simulated altitude group was not significantly different from that of the 5000 m simulated altitude group (P > 0.05). The plasma motilin level of the 5000 m simulated altitude group was 88 pg/ml +/- 19 pg/ml, significantly lower than that of the ground level group (123 pg/ml +/- 28 pg/ml, P < 0.01), in contrast, the plasma NO level of the 5000 m simulated altitude group was 106 micromol/L +/- 24 micromol/L, significantly higher than that of the ground level group (80 micromol/L +/- 18 micromol/L, P < 0.01). Acute exposure to hypobaric hypoxia at the height of 5000 m inhibits the gastric emptying and intestinal propulsion. Mosapride may alleviate the inhibitory effect of hypobaric hypoxia on gastric emptying. Decrease of plasma motilin and elevation of NO level may be the main mechanism of inhibition of gastrointestinal motility by hypobaric hypoxia.

Ghrelin, motilin, insulin concentration in healthy infants in the first months of life: relation to fasting time and anthropometry

This study aimed to investigate: (i) the relation between fasting time and serum ghrelin, motilin and insulin concentrations and (ii) the correlations between these hormones and anthropometrical parameters of infants in the first 18 months of life. A cross-sectional study on 62 term infants was performed. Blood samples for hormonal assay were obtained at least 1 h after feeding. Weight, length and head circumference were recorded. Plasma ghrelin, motilin and insulin concentrations were determined by radioimmunoassay. Ghrelin and motilin had a significant direct correlation with fasting time (r = 0.447; P < 0.001 and r = 0.36; P = 0.004, respectively). We observed a negative influence of insulin on ghrelin levels (beta = -0.32; P = 0.036). Plasma ghrelin levels correlated significantly with age (r = 0.45, P < 0.001), weight (r = 0.31, P = 0.013), head circumference (r = 0.35, P = 0.006) and length (r = 0.39, P = 0.001). A significant correlation emerged between motilin and age (r = 0.45, P < 0.001), weight (r = 0.43, P = 0.001), head circumference (r = 0.47, P < 0.001) and length (r = 0.48, P < 0.001). Fasting influence on serum ghrelin concentration confirms the role of this hormone as a physiological meal initiator also in infancy. The correlation between ghrelin, anthropometrical parameters and age supports the hypothesis that this hormone could exert an important influence on growth in the first months of life. Considering motilin, age and weight might play a role in determining its secretion; motilin could be considered one of the numerous factors involved in long-term regulation of energy balance.

Advances in mechanisms of postsurgical gastroparesis syndrome and its diagnosis and treatment

Postsurgical gastroparesis syndrome (PGS) is a complex disorder characterized by post-prandial nausea and vomiting, and gastric atony in the absence of mechanical gastric outlet obstruction, and is often caused by operation at the upper abdomen, especially by gastric or pancreatic resection, and sometimes also by operation at the lower abdomen, such as gynecological or obstetrical procedures. PGS occurs easily with oral intake of food or change in the form of food after operation. These symptoms can be disabling and often fail to be alleviated by drug therapy, and gastric reoperations usually prove unsuccessful. The cause of PGS has not been identified, nor has its mechanism quite been clarified. PGS after gastrectomy has been reported in many previous studies, with an incidence of approximately 0.4-5.0%. PGS is also a frequent complication of pylorus-preserving pancreatoduodenectomy (PPPD), and the complication occurs in the early postoperative period in 20-50% of patients. PGS caused by pancreatic cancer cryoablation (PCC) has been reported about in 50-70% of patients. Therefore, PGS has a complex etiology and might be caused by multiple factors and mechanisms. The frequency of this complication varies directly with the type and number of gastric operations performed. The loss of gastric parasympathetic control resulting from vagotomy contributes to PGS via several mechanisms. It has been reported that the interstitial cells of Cajal (ICC) may play a role in the pathogenesis of PGS. Recent studies in animal models of diabetes suggest specific molecular changes in the enteric nervous system may result in delayed gastric emptying. The absence of the duodenum, and hence gastric phase III, may be a cause of gastric stasis. It was thought that PGS after PPPD might be attributable, at least in part, to delayed recovery of gastric phase III, due to lowered concentrations of plasma motilin after resection of the duodenum. The damage to ICC might play a role in the pathogenesis of PGS after PCC, for which multiple factors are possibly responsible, including ischemic and neural injury to the antropyloric muscle and the duodenum after freezing of the pancreatoduodenal regions or reduction of circulating levels of motilin. As the treatment of gastroparesis is far from ideal, non-conventional approaches and non-standard medications might be of use. Multiple treatments are better than single treatment. This article reviews almost all the papers related to PGS from various journals published in English and Chinese in recent years in order to facilitate a better understanding of PGS.

Save the Pylori

Save the Pylori

Effects of surface gastric pacing on gastric myoelectrical activity and plasma motilin in a canine model of gastric motility disorders

To investigate the effects of surface gastric pacing on gastric myoelectrical activity and plasma motilin concentration in a canine model of gastric motility disorders. Ten healthy mongrel dogs were divided into two groups: an experimental group of six dogs and control group of four dogs. The model of gastric motility disorders was established in the experimental group with truncal vagotomy combined with injection of glucagon. Gastric serosal myoelectrical activity was recorded with a four-channel computer analysis device. Plasma motilin concentration was measured with a radioimmunoassay (RIA) kit. Surface gastric pacing at 1.1-1.2-fold the intrinsic slow-wave frequency superimposed with a series of high frequency pulses (10-30 Hz) was performed for 45 min daily for 1 month in the conscious dogs. The basic electrical rhythm (BER) amplitude (2.32 +/- 0.35 mV) and propagation velocity (4.06 +/- 0.40 cm/s) of the dogs with bilateral truncal vagotomy in the fed state decreased more significantly than those of the controls (4.25 +/- 0.12 mV, 6.92 +/- 0.24 cm/s) (P < 0.03). After long-term surface gastric pacing, the BER amplitude (3.97 +/- 0.19 mV) and propagation velocity (5.57 +/- 0.48 cm/s) was increased significantly compared with before pacing (P < 0.05). Postprandial gastric dysrhythmias were provoked by large doses of glucagon; the percentage of regular slow waves of the dogs with vagotomy was markedly reduced from 67.4 +/- 6.2% at baseline to 10.0 +/- 6.7% (P < 0.001), and that of the control was also decreased from 87.1 +/- 6.9% to 35.0 +/- 11.0% (P < 0.01), but the entrainment of gastric slow waves was 100% by means of gastric pacing at optimal parameters. There was a significant increase in the plasma concentration of motilin at the phase III of the interdigestive myoelectrical complex (IMC III) in the dogs with bilateral truncal vagotomy (baseline vs vagotomy, 184.29 +/- 9.81 pg/mL vs 242.09 +/- 17.22 pg/mL; P< 0.01). However, the plasma motilin concentration (212.55 +/- 11.20 pg/mL; P < 0.02) was decreased significantly after long-term gastric pacing. Before gastric pacing the plasma motilin concentration showed an equally negative correlation with the BER amplitude, and propagation velocity in the dogs with vagotomy in the fed state (r = -0.473, r = -0.807, P < 0.04), but after long-term gastric pacing, the plasma motilin concentration showed an equally positive correlation with the BER amplitude and propagation velocity (r = 0.523, r = 0.896, P < 0.02). Surface gastric pacing with optimal pacing parameters is able to entrain completely propagated slow waves, improve the parameters of gastric myoelectrical activity and normalize gastric dysrhythmias induced by a pharmacological agent. Surface gastric pacing might be useful in the treatment of gastric dysrhythmia. The gastric myoelectrical activity correlated well with the plasma motilin concentration before and after pacing, which suggests that motilin could modulate the effect of gastric pacing through alteration of the gastric myoelectrical parameters.

Effects of gastric pacing on gastric emptying and plasma motilin.

To investigate the effects of gastric pacing on gastric emptying and plasma motilin level in a canine model of gastric motility disorders and the correlation between gastric emptying and plasma motilin level. Ten healthy Mongrel dogs were divided into: experimental group of six dogs and control group of four dogs. A model of gastric motility disorders was established in the experimental group undergone truncal vagotomy combined with injection of glucagon. Gastric half-emptying time (GEt(1/2)) was monitored with single photon emission computerized tomography (SPECT), and the half-solid test meal was labeled with an isotope-(99m)Tc sulfur colloid. Plasma motilin concentration was measured with radioimmunoassay (RIA) kit. Surface gastric pacing at 1.1-1.2 times the intrinsic slow-wave frequency and a superimposed series of high frequency pulses (10-30 Hz) was performed for 45 min daily for a month in conscious dogs. After surgery, GEt(1/2) in dogs undergone truncal vagotomy was increased significantly from 56.35+/-2.99 min to 79.42+/-1.91 min (P<0.001), but surface gastric pacing markedly accelerated gastric emptying and significantly decreased GEt(1/2) to 64.94+/-1.75 min (P<0.001) in animals undergone vagotomy. There was a significant increase of plasma level of motilin at the phase of IMCIII (interdigestive myoelectrical complex, IMCIII) in the dogs undergone bilateral truncal vagotomy (baseline vs vagotomy, 184.29+/-9.81 pg/ml vs 242.09+/-17.22 pg/ml; P<0.01). But plasma motilin concentration (212.55+/-11.20 pg/ml; P<0.02) was decreased significantly after a long-term treatment with gastric pacing. Before gastric pacing, GEt(1/2) and plasma motilin concentration of the dogs undergone vagotomy showed a positive correlation (r=0.867, P<0.01), but after a long-term gastric pacing, GEt(1/2) and motilin level showed a negative correlation (r=-0.733, P<0.04). Surface gastric pacing with optimal pacing parameters can improve gastric emptying parameters and significantly accelerate gastric emptying and can resume or alter motor function in a canine model of motility disorders. Gastric emptying is correlated well with plasma motilin level before and after pacing, which suggests that motilin can modulate the mechanism of gastric pacing by altering gastric motility.

Motilin kinetics and effects on proximal stomach in patients with functional dyspepsia (FD) and healthy volunteers

Motilin is involved in the regulation of upper gastrointestinal (GI) motility and it has been suggested that motilin may play a role in the pathogenesis of poorly understood clinical entities such as FD. The present study was performed in order to further investigate the effects of exogenous motilin on the proximal stomach of healthy volunteers and patients with FD. Eight healthy volunteers and 12 FD patients (Rome II, early satiety) were infused with synthetic motilin (4 pmol kg−1 min−1) or placebo over 90 min in a double-blind, randomized, cross-over study. Proximal gastric volume was measured with a barostat device at a predefined pressure and during isobaric distensions. Abdominal symptoms such as fullness, nausea and abdominal pain were scored by Visual Analogue Scales (VAS). Gallbladder volume was measured by ultrasonography and plasma motilin concentrations were measured with an radioimmuno-assay. Treatment effect within a patient group was estimated with paired Student's t-test, and differences between the two groups were investigated using unpaired Student's t-test. Data are given as mean (± s.d.) and differences are expressed with the corresponding 95% confidence intervals (95% CI). The plasma concentration–time curves for motilin were similar between healthy volunteers and patients. Baseline gastric volumes were similar for both groups; 269 ± 147 ml (healthy volunteers) and 265 ± 98 ml (FD patients). Compared with placebo, motilin reduced proximal gastric volume by 112 ml (95% CI: 29, 195 ml) in FD patients and by 96 ml (95% CI: −7.3, 200) in healthy volunteers (Figure 1). Figure 1 Mean (s.d.) proximal gastric volume (ml) during the constant pressure procedure (MDP + 3 mmHg), corrected for baseline volume in dyspeptic patients (n = 12) during motilin (▪) and placebo (□) and in healthy volunteers (n = 8) during motilin ... In the FD-patients, motilin decreased maximal compliance by 76.1 ml mm Hg−1 (95% CI: 8.8, 143.4) compared with placebo, and was similar to that observed in healthy volunteers. Patients were significantly more nauseous (p = 0.04) during motilin compared with placebo, whereas healthy volunteers did not experience nausea. Motilin reduced gall bladder volume by 33% (95% CI: 20, 45) in the FD patients and by 6% (95% CI: −13, 25) in the healthy volunteers. The difference in gall bladder volume was significant between the groups. Motilin significantly reduced proximal gastric volume and compliance in dyspeptic patients and healthy volunteers by a similar magnitude. In dyspeptic patients, motilin induced nausea, and evoked a greater gall bladder volume reduction.

Biliary sphincter motility after neural isolation of the pancreatoduodenal region in conscious dogs

Background. Several neural and hormonal factors are known to affect the motility of the sphincter of Oddi. However, the precise mechanisms of the control of sphincter motility have not been completely explored. We investigated the relationship of canine biliary sphincter motility when it is extrinsically denervated by neural isolation of the pancreatoduodenal region. Methods. Interdigestive and postprandial sphincter motility in a denervated pancreatoduodenal segment and effects of cholecystokinin-octapeptide were studied in 7 conscious dogs. Data were compared with those of 7 neurally intact control dogs. Results. After extrinsic denervation of the pancreatoduodenal region, sphincter motility exerted a cyclic change in concert with the duodenal myoelectric cycles; this change involved short cyclic bursts of motor activity, which gradually increased in intensity. The increase in the cyclic bursts of motor activity was also cyclic and associated with an increase in the plasma motilin concentration. Neural isolation of the pancreatoduodenal region increased sphincter basal pressure and motility index (integral per minute). In the denervated biliary sphincter, the feeding pattern and temporary inhibitory effect of feeding, as seen in controls, were absent, which suggests the role of extrinsic nerves in delivering bile into the duodenum after feeding. In the denervated dogs, cholecystokinin-octapeptide caused excitation of the sphincter activity, instead of relaxation observed in controls. Conclusions. Extrinsic innervation to the pancreatoduodenal region has an inhibitory effect on biliary sphincter motility. Abnormalities in extrinsic innervation to the biliary sphincter might increase the resistance of the sphincter to the bile flow and induce bile stagnation. (Surgery 2002;131:139-48.)

MOTILIN LEVELS AND ELECTROGASTROENTEROGRAM STUDIES IN HYPOTHYROIDISM

To study the relationship between gastrointestinal dysfunction and motilin in patients with hypothyroidism. The plasma motilin concentration was measured by radiommunoassay (RIA) in 30 patients with hypothyroidism and also in 30 controls. At the same time, the electrogastroenterogram was also taken. Among the hypothyroidism patients, 56.6% had decreased gastric motility, especially in gastric body and greater gastric curvature; 86.6% had decreased colonic motility, especially in the left half of the colon. There were no significant differences of plasma motilin concentration between patients with hypothyroidism and controls (P>0.05). There were also no differences between pre-treatment and post-treatment individuals, but significant differences were observed in the electrogastroenterogram. We conclude that the plasma motilin concertration in hypothyroidism patients was the same as that in normal patients, and that electrogastroenterogram studies in patients with gastrointestinal dysfunction may be valuable.

Effect of electroacupuncture in Weijing points on gastrointestinal interdigestive migrating motor complex and brain gut peptides release in dogs

Interdigestive gastrointestinal migrating motor complex (MMC) activities were recorded by strain gauge implanted on the serosa in 7 conscious dogs. We studied the effects of electroacupuncture (EAP) Weijing points Zusanli (S36), Tianshu (S25), Liangmen (S21) on MMC and release of motilin and gastrin, and compared them with that of EAP Pangguangjing points. The results indicated that EAP Weijing points could not only strengthen MMC contractions in antrum, duodenum and proximal jejunum, but also increase plasma concentration of motilin and gastrin. Anti-motilin serum, proglumide, atropine, or hexamethonium could markedly block the effect of EAP on reinforcing MMC contraction and release of motilin and gastrin. We could get the conclusions that such enhancing effect of EAP Weijing points on MMC and brain-gut peptides release is mediated by motilin and gastrin, on which both cholinergic nerve and sympathetic nerve play important roles.