Researches on Gastric Interdigestive Pressure Activity: Methods, Analysis and Interpretation.

Aims: To give researches on gastric interdigestive pressure activity, including gastrointestinal (GI) physiological motility recording method, data processing and analysis method, as well as to give reasonable interpretation on how to generate such gastric pressure activity. Study design: Basic application study. Place and Duration of Study: School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology (USST), between June 2010 and October 2011. Methodology: We introduced a telemetric method to get the gastric physiological pressure activity inside the GI tract and the general process for processing such gastric Migrating Motor Complex (MMC) pressure activity including the process of abnormal value removing, medians of five-three-Hanning (53H) weighted average smoothing, and the fluctuation frequency estimation. Results: Using the process of abnormal value removing, medians of five-three-Hanning (53H) weighted average smoothing, and the fluctuation frequency estimation, we well obtained gastric interdigestive pressure activity (MMC). Conclusion: The methods introduced in the paper including abnormal value removing, the 53H weighted average smoothing, and the fluctuation frequency estimation were helpful for researches on gastric interdigestive pressure activity.

Effect of thyroidal motilin on gastric motility and central modulation in rat thyroid / 中华内分泌代谢杂志

Objective To research the functional role of thyroidal motilin and the effects of electric excitation of the paraventricular nuclei(PVN) on gastric motility and the levels of motilin in thyroid and plasma.Methods The expression of motilin in rat and human thyroid was detected by immunofluorescence staining.A phase Ⅲ-like contraction was recorded before and after thyroidectomy and after PVN excitation.The changes in concentrations of plasma FT3,FT4 and motilin were determined via radioimmunoassay (RIA).c-Fos expression of PVN after thyroidectomy and motilin expression in thyroid after PVN excitation were observed by immunohistochemical staining.Results There were motilin immunoreactive cells in rat and human thyroid.The phase Ⅲ-like contraction and concentration of motilin in plasma decreased significantly when measured on the second and fourth days after thyroidectomy(2d,P＜0.01 ;4d,P＜0.05).The expression of c-Fos in PVN after thyroidectomy was significantly increased(P＜0.05).An electric excitation of PVN could increase the concentration of motilin in plasma and thyroid and increase corresponding gastric motility in rats (P ＜0.05).The increased phase Ⅲ-like contraction by PVN excitation could be partially inhibited by administration of motilin receptor antagonist,GM-109 (P＜0.05).Excitation of PVN in thyroidectomized rats resulted in lower plasma motilin and less intense phase Ⅲ-like contraction of stomach,as compared with the sham operated control group(P＜0.05).Conclusion Motilin from the thyroid may be secreted into the peripheral plasma to affect gastric motility and PVN may modulate gastric motility and motilin expression in the thyroid.

Changes in Migrating Motor Complex after Bowel Obstruction in the Murine Ileum

PURPOSE: Partial obstruction of the small bowel causes hypertrophy of smooth muscle cells and enteric neurons. After small bowel obstruction, slow waves have also been reported to disappear or to be greatly reduced at the oral site of the obstruction in the murine ileum. The purpose of this research was to study the changes in migrating motor complexes (MMCs) after partial obstruction in order to compensate for the attenuated function of slow waves. METHODS: A ring of film (6 mm in length, 4 mm in internal diameter) was placed over the small intestine 5-6 cm oral to the ileocecal valve in 8-10 wk old female ICR mice. These rings resulted in a partial obstruction of the intestine after 2 wk. The mechanical activities of the small intestine were recorded and the amplitude, interval, and half-duration of the MMCs were analyzed. RESULTS: The MMCs from a partially obstructed ileum occurred every 1.58+/-1.06 min and had a half-duration of 6.90+/-5.54 sec. The interval and the half-duration of the control MMCs were 3.60+/-1.11 min and 31.5+/-11.4 sec, respectively. The difference in interval and the half-duration of the MMCs reached statistical significance (P=0.03; P=0.00). The amplitude and the area under the curve (AUC) of the MMCs of the obstructed ileum were much higher than those of the control (31.3+/-8.86 vs. 6.05+/-1.92 mN; 161.18+/-44.09 vs. 72.95+/-2.45 mN . sec/MMC wave; P=0.00, 0.02). CONCLUSION: The MMCs with higher amplitude and AUC, with shorter interval, and with shorter half-duration, compared with those of the control, were recorded from the partially obstructed murine ileum, reflecting efforts to overcome the effect of obstruction by increasing the power of contractions.

Effect of thyroid motilin on migrating motor complex in fasting rats / 第二军医大学学报

Objective: To investigate the effects of thyroid motilin (MTL) on migrating motor complex (MMC) in fasting rats. Methods: The distribution and quantitative expression of motilin in the thyroids were detected by immunohistochemistry and radioimmunoassay. We also observed the effect of thyriod motilin on the MMC by recording the gastrointestinal motility in conscious rats. Results: Tail vein injection of MTL increased MMC in antrum and duodenum in a dose-dependent manner, as manifested by increased contraction frequency and amplitude (P<0.05, P<0.01). However, the contraction frequency and amplitude were significantly decreased after injection of MTL-R antagonist GM109(P<0.05). GM109 could obviously block the promoting effect of MTL on MMC. Removing left thyroid significantly increased MMC cycle, contraction amplitude, and decreased contraction frequency (P<0.05). Injection of anti-MTL serum into the thyroids could significantly promote MMC and increase the frequency and amplitude of contraction (P<0.05). Immunohistochemistry demonstrated that motilin immunoreactive (MTL-IR) cells, together with calcitonin (CT) ,were observed in the thyroids, indicating the expression of MTL in thyroid C-cells. Radioimmunoassay analyses displayed that MTL level in the duodenal mucosa was 128.02 and 100.57 times those in the antrum and thyroid, respectively. Conclusion: MTL is expressed in the thyroid C-cell and participates in the regulation of MMC.

A research of migrating motor complex in patients with irritable bowel syndrome / 中华内科杂志

Objectives To compare the migrating motor complex (MMC) in irritable bowel syndrome (IBS) patients with that in healthy controls. To explore whether discrete clustered contractions (DCC) are connected with abdominal pain in IBS patients. To improve the method of measuring gastroenteric motility (esp. jejunum). Methods By using 16-channel water-perfused catheter and manometry instruments, MMC in 16 cases of IBS with constipation (IBS-C), 18 cases of IBS with diarrhea (IBS-D) and 18 cases of healthy controls were monitored. Results The MMC durations of IBS-C and IBS-D patients were (127.5±25.5) min and (74.5±18.7) min, respectively. Comparision with those in the control group [(87.5±24.2) min]showed significant differences (P<0. 001). The contraction amplitudes of stage Ⅲ in different sites of IBS-C patients decreased significantly as compared with those in the controls [jejunum, (39.8±11.7) mm Hg vs. (61.1±14.1) mm Hg,P<0.001,1 mm Hg=0.133 kPa]. The propagation velocities of stage Ⅲ in different sites of IBS-C patients also decreased significantly as compared with those in the controls [jejunum, (1.8±0.9) cm/min vs. (2.6±0.8) cm/min,P<0.01].The contraction amplitudes of stage Ⅲ in different sites of IBS-D patients increased significantly as compared with those in the controls [jejunum, (69.7±20.5) mm Hg vs. (61.1±14.1) mm Hg, P<0.01]. The propagation velocities of stage Ⅲ in different sites of IBS-D patients also increased significantly as compared with those in the controls [jejunum, (4.1±2.5) cm/min vs. (2.6±0.8) cm/min, P < 0. 01]. DCC incidences of IBS-C and IBS-D were 87.5% and 88. 8%, respectively. Comperision with those in the normal group (83.3%) did not show significant difference (P>0.05). The prevalences of abnormal stage Ⅲ contractions (include disturbances and interferences of stage Ⅲ contractions) in IBS-C and IBS-D patients were 68.8% and 66. 7%, respectively; there were no significant differences between the two groups (P > 0. 05). However abnormal stage Ⅲ contractions did not exist in healthy controls. Conclusions (1) The MMC of IBS-C and IBS-D patients are changed, as compared with that in healthy people; this implies that small intestinal motility dysfunction is one of the pathogenetic factors of IBS. The abnormal stage Ⅲ contractions in jejunum may be a predominant change in IBS gastroenteric motility. (2) No apparent connection is found between DCC and pain in IBS. (3) By using 16-channel water-perfused catheter, we first carried out the method of monitoring jejunum contractions in China. Parameters of MMC in Chinese healthy people were investigated, esp. those of jejunum.

Percutaneous Transhepatic Biliary Manometry / 대한소화기학회지

Perendoscopic biliary manometry may not represent the overall sphincter of Oddi (SO) motility, as the recording time is relatively short and it is possibly influenced by the presence of an endoscope in duodenum and air inflation. Percutaneous transhepatic biliary manometry of SO permits long-term recordings without patient discomfort and risk of complications. We investigated the change of human SO motility and the correlation between SO motility and migrating motor complex (MMC) of the small bowel in a fasting state by long-term simultaneous manometric examination of SO and small bowel. During long-term manometry, MMC-like cyclic activities of SO were observed, which consiered to be MMC of SO. It coordinated well with MMC of the small bowel, except that SO was not quiescent during phase I MMC of the small bowel. In addition, the basal pressure of SO changed in accordance with the phases of SO motility. Percutaneous transhepatic biliary manometry also permits prolonged manometric studies to investigate normal physiologic reflexes such as gastroduodeno-sphincteric, cholecysto-sphincteric and choledocho-sphincteric reflexes, and the influence of cholecystectomy on SO motility in humans.

Effect of SC-435 on the gastrointestinal migrating myoelectric complex in guinea pigs / 中南大学学报(医学版)

Objective To determine whether SC-435, a new ileal apical sodium-codependent bile acid transporter (IBAT) inhibitor, can alter the gastrointestinal motility in guinea pigs. Methods Sixty guinea pigs received regular diet or IBAT inhibitor (SC-435) diet for 2, 4, and 8 weeks, respectively. At the end of the feeding period, the gallbladder motility was assessed and then four bipolar silver electrodes were implanted on the antrum, duodenum, jejunum, and ileum. Seven days later, migrating motor complex (MMC) was recorded and the total bile acid pool size was measured according to the isotope dilution principle in the meantime. Results After feeding SC-435, the gallbla-dder motility was declined in the 4-week group and the 8-week group. The bile acid pool size decreased by 17.11% (P<0.05) in the 4-week group and 48.35% (P<0.05) in the 8-week group. The places of origin of MMC were changed where antral origins (37%) and duodenal origins (46%) decreased whereas jejunal origins (17%) increased. The MMC cycle period was prolonged in the duodenum (1.16 times in the 4-week group, P< 0.05; 1.38 times in the 8-week group, P<0.05) whereas MMC amplitude fell in the duodenum (10.58% in the 4-week group, P<0.05; 49.17% in the 8-week group, P<0.05). There were not significant differences in all parameters of MMC between the control group and the 2-week group in guinea pigs. Conclusion The IBAT inhibitor (SC-435) reduces the bile acid pool size and inhibits the MMC cycle activity. MMC is related to the enterohepatic circulation of bile acids, which is consistent with the changes of the bile acid pool size in guinea pigs.

Changes of 24-hour gastric motility and myoelectric activity in patients with functional dyspepsia / 中华消化杂志

Objective To investigate the changes of 24 hour gastric motility and myoelectric activity in patients with functional dyspepsia (FD) and to compare the differences of these changes among the different clinical types of FD. Methods 24 hour gastric and duodenal manometry combined with 24 hour electro gastrography was carried out in 31 patietns with FD and 20 normal controls. Results Compared with normal controls, patients with FD had less frequency and longer duration of migrating motor complex (MMC), and phase Ⅰ plus phase Ⅱ duration were also greatly increased ( P

Experimental study on regulation of bile duct motility by gastrointestinal migrating motor complex / 中华消化杂志

Objective In order to elucidate the mechanism of migrating motor complex (MMC) in prophylaxis and treatment of cholelithiasis,the relationship and interaction between MMC and the bile duct motility were investigated. Methods Forty five adult guinea pigs were allocated into three groups with 15 each. The guinea pigs in control,prucalopride and dibazol groups were fed with saline (0.15 ml/100 g),prucalopride (0.01 mg/100 g) or dibazol (0.6 mg/100 g),respectively. The myoelectrical activities of antrum,duodenum,gallbladder(GB) and sphincter of Oddi(SO) of guinea pigs were recorded simultaneously before and after administration via implanted silver electrodes of the muscle layer. Results Positive correlation in frequency and strength of spontaneous myoelectrical activity was demonstrated among antrum,duodenum,GB and SO before administration( P

Effect of thyroid motilin on migrating motor complex in fasting rats / 第二军医大学学报

Objective:To investigate the effects of thyroid motilin(MTL) on migrating motor complex(MMC) in fasting rats.Methods: The distribution and quantitative expression of motilin in the thyroids were detected by immunohistochemistry and radioimmunoassay.We also observed the effect of thyriod motilin on the MMC by recording the gastrointestinal motility in conscious rats.Results: Tail vein injection of MTL increased MMC in antrum and duodenum in a dose-dependent manner,as manifested by increased contraction frequency and amplitude(P

Effect of erythromycin on interdigestive and postprandial gastrointestinal contractile activity and its mechanism in dogs / 中国药理学通报

AIM To observe the effect of intra- venous injection of erythromycin (EM) on interdigestive migrating motor complex (MMC) and postprandial gastrointestinal contraction in conscious dogs, and to study its possible mechanism. METHODS Gastrointestinal contractile activity was recorded using low compliance capillary water per fusion manometric system. EM was administered intravenously during phase I and after meal, and blood samples were drawn for measuring plasma motilin concentra- tions. RESULTS ①Plasma motilin levels showed cyclical fluctuations in different phases of MMC, and plasma motilin reached peak during phaseⅢ and lowest during phase Ｉ. ②EM induced phase Ⅲ -like contractions in the antrum and duodenum, which was not accompanied by a peak in plasma motilin level. The optimum dose of EM for resulting in a premature phaseⅢ with the same characteristics as the spontaneously occurring phaseⅢ was established to be 0. 5 mg.kg-1. The dose of 10 mg.kg-1 EM induced gas- trointestinal continuous contractions and duodeno-gas-tric retrograde peristalsis which was associated with retching and vomiting. ③Atropine obviously inhibited EM-induced phase Ⅲ activity in the antrum and duodenum. GEM powerfully enhanced postprandial gastrointestinal contractile activity. CONCLUSIONS The results suggests that EM is a potent prokinetic agent. The mechanism is not related to the release of motilin, but may be mediated partially by cholinergic pathway.