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Proximal Jejunum (proximal + jejunum)
Selected AbstractsIndirect evidence for increased mechanosensitivity of jejunal secretomotor neurones in patients with idiopathic bile acid malabsorptionACTA PHYSIOLOGICA, Issue 2 2009A. Bajor Abstract Aim:, The interdigestive motor rhythm, the migrating motor complex (MMC), is accompanied by active secretion of chloride during periods of distally propagating maximal motor activity (MMC phase III). We studied the behaviour of this system in bile acid malabsorption (BAM), a relative common cause of chronic diarrhoea. We measured motor activity and transmucosal potential difference (PD, reflecting active chloride secretion), in the proximal jejunum in healthy controls (n = 18) and in a group of patients with BAM (n = 11). The phase III-generated voltage was related to the degree of BAM quantified by the 75SeHCAT test. Methods:, We used a multi-channel intestinal infusion system to simultaneously measure jejunal pressure and PD. Saline passing calomel half-cells was infused into the jejunum and subcutaneously. Pressure and PD were recorded in the fasting state and after a test meal. Results:, In the absence of motor activity, jejunal PD was not significantly different from zero in either group. During MMC phase III, PD reached significantly higher mean and peak levels in BAM patients. The product of MMC phase III length multiplied by voltage, over 3 h, was also significantly higher in BAM patients (controls: median 307 mV × cm, range 70,398; BAM: median 511, range 274,2271, P < 0.01). This value was also significantly correlated with the degree of BAM as reflected by the 75SeHCAT test (P < 0.05). Conclusion:, Phase III induced jejunal secretion may be upregulated in BAM patients, resulting in overload of colonic reabsorption capacity. [source] PARTIAL REGRESSION OF DUODENAL LESIONS OF INTESTINAL FOLLICULAR LYMPHOMA AFTER ANTIBIOTIC TREATMENTDIGESTIVE ENDOSCOPY, Issue 4 2010Tomonori Yaguchi A 51-year-old man was referred to our hospital because of duodenal lesions of lymphoma. Endoscopy showed multiple tiny smooth whitish granules in the second portion of the duodenum including the papilla of Vater. Biopsy specimens showed medium-sized centrocyte-like cells forming lymphoid follicles, and immunohistology showed positive staining for bcl-2 and CD10. A small bowel series showed multiple granular lesions extending from the second portion of the duodenum to the proximal jejunum and the proximal ileum. On the basis of these findings, the tumor was diagnosed as stage I follicular lymphoma (FL). Although the patient was negative for Helicobacter pylori, he underwent antibiotic treatment. The lesions improved 3 months after antibiotic treatment, but biopsy specimens showed residual lymphoma cells. The patient therefore received combination chemotherapy with rituximab. Endoscopy 4 months later showed regression of FL, and there was no evidence of recurrence during 3 years of follow up. The partial regression of duodenal lesions of intestinal FL may be due to the effect of antibiotic treatment. [source] Influence of deoxynivalenol on the D -glucose transport across the isolated epithelium of different intestinal segments of laying hensJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5-6 2007W. A. Awad Summary Deoxynivalenol (DON) decreases glucose absorption in the proximal jejunum of laying hens in vitro and this effect is apparently mediated by the inhibition of the sodium d -glucose co-transporter. DON could modulate the sugar transport of other intestinal regions of chickens. For this purpose, we have measured the effects of DON on the Na+d -glucose co-transporter, by addition of DON after and before a glucose addition in the isolated epithelium from chicken duodenum, jejunum, ileum, caecum and colon by using the Ussing chamber technique in the voltage clamp technique. The data showed in all segments of the gut that the addition of d -glucose on the mucosal side produced an increase in the current (Isc) compared with the basal values, the Isc after glucose addition to the small intestine was greater than the Isc of the large intestine compared with the basal values, specially of the jejunum (p < 0.002), indicating that the jejunum is the segment that is the best prepared for Na+ - d -glucose co-transport. Further addition of 10 ,g DON/ml to the mucosal solution decreased the Isc in all segments and the Isc returned to the basal value, especially in the duodenum and mid jejunum (p < 0.05). In contrast, the addition of 5 mmol d -glucose/l on the mucosal side after incubation of the tissues with DON in all segments had no effect on the Isc (p > 0.05), suggesting that DON previously inhibited the Na+d -glucose co-transport. The blocking effects of DON in duodenum and jejunum were greater than the other regions of the gut. It can be concluded that the small intestine of laying hens has the most relevant role in the carrier mediated glucose transport and the large intestine, having non-significant capacity to transport sugars, appears to offer a minor contribution to glucose transport because the surface area is small. The effect of d -glucose on the Isc was reversed by DON in all segments, especially in the duodenum and jejunum, suggesting that DON entirely inhibited Na+ - d -glucose co-transport. This finding indicates that the inhibition of Na+ co-transport system in all segments could be an important mode of action for DON toxicity of hens. Zusammenfassung Deoxynivalenol (DON) erniedrigt in vitro die Glukoseabsorption im proximalen Jejunum von Legehennen. Dieser Effekt ist vermutlich durch eine Hemmung des Natrium- d -Glukose-Cotransportsystems bedingt. DON könnte außerdem den Glukosetransport in anderen Segmenten des Darms beeinflußen. Zu diesem Zweck haben wir Wirkungen von DON auf das Natrium- d -Glukose-Cotransportsystem gemessen, indem wir DON nach und vor einer Glukosezugabe auf isolierte Darmepithelien des Duodenums, Jejunums, Ileums, Caecums und des Kolons mittels der Ussing-Kammer-Technik in der Volt-Klemmtechnik einwirken ließen. Die erzielten Daten wiesen in allen Segmenten des Darms verglichen mit den Basalwerten einen Anstieg im Strom (Isc) auf, wobei die Isc des Dünndarms bei Glukosegabe signifikant größer als die des Dickdarms waren, was darauf hinweist, dass das Jejunum am besten für den Glukosetransport geeignet war. Eine DON-Zugabe von 10 ,g/ml zur mukosalen Lösung schwächte den Isc in allen Segmenten, wobei die Isc speziell im Duodenum und mittleren Jejunum zum Ausgangswert zurück kehrten. Im Gegensatz dazu brachte die mukosale Glukosezugabe nach der DON-Inkubation keinen signifikanten Anstieg der Isc (p > 0,05), was auf eine durch DON hervorgerufene Blockade des Natrium- d -Glukose-Cotransportsystems schließen ließ. Es kann daraus geschlossen werden, dass der Dünndarm von Legehennen den bedeutendsten Einfluß im Glukosetransportmechanismus nimmt und der Dickdarm aufgrund einer kleineren Oberfläche einen geringeren Beitrag zum Glukosetransport leistet. Dem Isc steigernden Effekt der Glukose konnte signifikant durch DON in den Darmsegmenten besonders im Duodenum und im Jejunum entgegen gewirkt werden, was auf eine umfassende Hemmung des Natrium- d -Glukose-Cotransportsystems hinweist. Die Resultate weisen darauf hin, dass eine Hemmung des Natrium- d -Glukose-Cotransportsystems in allen Darmsegmenten eine wichtige Rolle in der DON-Toxizität für die Henne darstellen könnte. [source] Dual pulse intestinal electrical stimulation normalizes intestinal dysrhythmia and improves symptoms induced by vasopressin in fed state in dogsNEUROGASTROENTEROLOGY & MOTILITY, Issue 5 2007H. Qi Abstract, To assess effects of dual pulse intestinal electrical stimulation (DPIES) on intestinal dysrhythmia and motility, and symptoms induced by vasopressin in conscious dogs. The study was performed in three postprandial sessions (control; vasopressin; DPIES) in six dogs with two pairs of electrodes chronically implanted on the serosal surface of the proximal jejunum and with a chronic duodenal fistula. A manometric catheter was advanced into the small intestine via the intestinal cannula. Motility and intestinal slow waves were recorded. Symptoms were assessed. During vasopressin infusion, the percentage of normal intestinal slow wave frequency was decreased (P < 0.01), reflected as a significant increase in the percentage of both bradygastria and tachygastria; the motility index decreased (P < 0.01) and the symptom score increased (P < 0.01). In the session of DPIES, the percentage of normal slow wave frequency was recovered (P < 0.05 vs vasopressin), attributed to a reduction in both bradyarrhythmia and tachyarrhythmia; the symptom score was reduced (P < 0.05 vs vasopressin); the motility index was not significantly increased. These results suggest that vasopressin induces intestinal dysrhythmia and emetic symptoms and inhibits intestinal motility. Dual pulse intestinal electrical stimulation is capable of improving intestinal dysrhythmia and emetic symptoms but not impaired intestinal motility induced by vasopressin. [source] Effects of 1,,25-dihydroxyvitamin D3 on transporters and enzymes of the rat intestine and kidney in vivoBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 1 2010Edwin C. Y. Chow Abstract 1,,25-Dihydroxyvitamin D3 (1,25(OH)2D3), the natural ligand of the vitamin D receptor (VDR), was found to regulate bile acid related transporters and enzymes directly and indirectly in the rat intestine and liver in vivo. The kidney is another VDR-rich target organ in which VDR regulation on xenobiotic transporters and enzymes is ill-defined. Hence, changes in protein and mRNA expression of nuclear receptors, transporters and enzymes of the rat intestine and kidney in response to 1,25(OH)2D3 treatment (0 to 2.56,nmol/kg/day intraperitoneally in corn oil for 4 days) were studied. In the intestine, protein and not mRNA levels of Mrp2, Mrp3, Mrp4 and PepT1 in the duodenum and proximal jejunum were induced, whereas Oat1 and Oat3 mRNA were decreased in the ileum after 1,25(OH)2D3 treatment. In the kidney, VDR, Cyp24, Asbt and Mdr1a mRNA and protein expression increased significantly (2- to 20-fold) in 1,25(OH)2D3 -treated rats, and a 28-fold increase of Cyp3a9 mRNA but not of total Cy3a protein nor Cyp3a1 and Cyp3a2 mRNA was observed, implicating that VDR played a significant, renal-specific role in Cyp3a9 induction. Additionally, renal mRNA levels of PepT1, Oat1, Oat3, Ost,, and Mrp4, and protein levels of PepT1 and Oat1 were decreased in a dose-dependent manner, and the ,50% concomitant reduction in FXR, SHP, HNF-1, and HNF-4, mRNA expression suggests the possibility of cross-talk among the nuclear receptors. It is concluded that the effects of 1,25(OH)2D3 changes are tissue-specific, differing between the intestine and kidney which are VDR-rich organs. Copyright © 2009 John Wiley & Sons, Ltd. [source] The effect of equicaloric medium-chain and long-chain triglycerides on pancreas enzyme secretionCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 5 2002T. Symersky Summary It has been shown previously that medium chain triglycerides (MCT) do not affect gallbladder emptying and cholecystokinin (CCK) release. The effect of MCT on exocrine pancreas secretion in humans is unknown. We have compared the effect of enteral administration of MCT versus long chain triglycerides (LCT) on exocrine pancreatic secretion. Eight healthy subjects (three female, five male; mean age 22 ± 1·9 years) participated in two experiments, performed in random order. Duodenal contents, obtained by aspiration, were used to calculated the output of pancreatic enzymes and bilirubin. An equicaloric amount of either MCT or LCT (2 kcal min,1) oil was continuously administered in the proximal jejunum for 2 h. Gallbladder volume was measured by ultrasonography and blood samples were drawn for determination of CCK. The experiments consisted of 1 h basal secretion, 2 h of continuous oil administration and 1 h poststimulation. During the LCT feeding the pancreatic enzyme secretion, bilirubin output, gallbladder emptying and CCK release increased significantly (P<0·05) over basal levels. MCT had no effect on pancreatic enzyme secretion nor gallbladder emptying or CCK release. We conclude that enteral administration of MCT in the proximal jejunum does not stimulate exocrine pancreatic secretion nor gallbladder contraction or CCK release, in contrast to an equicaloric amount of LCT. [source] | |||||||||||||