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Ong ES, Alassas MA, Bogner PN, Bullard Dunn K, Chey WY, Gibbs JF. Total Gastrectomy for Gastric Dysplasia in a Patient With Attenuated Familial Adenomatous Polyposis Syndrome. J Clin Oncol 2008; 26:3641-2. [DOI: 10.1200/jco.2008.16.7056] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Affiliation(s)
- Evan S. Ong
- Roswell Park Cancer Institute, Buffalo, NY; Department of Surgery, University at Buffalo, State University of New York, Buffalo, NY
| | - Mohamed A. Alassas
- Roswell Park Cancer Institute, Buffalo, NY; Department of Surgery, University at Buffalo, State University of New York, Buffalo, NY
| | | | - Kelli Bullard Dunn
- Roswell Park Cancer Institute, Buffalo, NY; Department of Surgery, University at Buffalo, State University of New York, Buffalo, NY
| | - William Y. Chey
- Rochester Institute for Digestive Diseases and Sciences, Rochester, NY
| | - John F. Gibbs
- Roswell Park Cancer Institute, Buffalo, NY; Department of Surgery, University at Buffalo, State University of New York, Buffalo, NY
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Yacyshyn B, Chey WY, Wedel MK, Yu RZ, Paul D, Chuang E. A randomized, double-masked, placebo-controlled study of alicaforsen, an antisense inhibitor of intercellular adhesion molecule 1, for the treatment of subjects with active Crohn's disease. Clin Gastroenterol Hepatol 2007; 5:215-20. [PMID: 17296530 DOI: 10.1016/j.cgh.2006.11.001] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS The aim of this study was to compare the safety and efficacy of alicaforsen, a first-generation antisense inhibitor of intercellular adhesion molecule 1, with placebo in subjects with active Crohn's disease, a disorder in which intercellular adhesion molecule 1 is overexpressed. METHODS In 2 identical double-masked, placebo-controlled studies, 331 subjects with active Crohn's disease were treated with either alicaforsen (221 subjects) or placebo (110 subjects) administered via 2-hour intravenous infusion 3 times a week for 4 weeks. Patients then returned for follow-up every 2 weeks. The primary end point was clinical remission by week 12. Secondary end points included clinical response and remission in relation to previous use of other biologics including tumor necrosis factor-alpha antagonists and presence of fistulous disease. RESULTS The results, whether combined or analyzed individually, failed to demonstrate statistical significance as a measure of its primary outcome (alicaforsen 33.9% vs placebo 34.5%; P = .89). In addition, no statistical differences in response were observed between alicaforsen and placebo in subjects who were previously treated with anti-tumor necrosis factor-alpha therapy or had baseline fistulizing disease. There were no significant differences in adverse events from placebo apart from a higher infusion reaction rate. CONCLUSIONS In the subject population studied, alicaforsen failed to demonstrate efficacy in any of its primary outcome measures. Alicaforsen was well-tolerated.
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Affiliation(s)
- Bruce Yacyshyn
- Rochester Institute for Digestive Diseases and Science, Rochester, New York, USA.
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Burakoff R, Barish CF, Riff D, Pruitt R, Chey WY, Farraye FA, Shafran I, Katz S, Krone CL, Vander Vliet M, Stevens C, Sherman ML, Jacobson E, Bleday R. A phase 1/2A trial of STA 5326, an oral interleukin-12/23 inhibitor, in patients with active moderate to severe Crohn's disease. Inflamm Bowel Dis 2006; 12:558-65. [PMID: 16804392 DOI: 10.1097/01.ibd.0000225337.14356.31] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Intestinal inflammation associated with Crohn's disease is characterized by a type 1 helper T cell response and elevated levels of interleukin (IL)-12. We report our clinical experience with a novel oral IL-12/IL-23 inhibitor (STA 5326) for the treatment of active Crohn's disease. MATERIALS AND METHODS We conducted an open-label, dose-escalating trial of the orally delivered small molecule immunomodulator STA 5326 in 73 patients with active Crohn's disease (Crohn's disease activity index [CDAI] 220-450, inclusive). Five cohorts of patients were treated for up to 4 weeks with 14 mg twice a day (bid), 35 mg daily (qd), 28 mg bid, 35 mg bid, or 70 mg qd. The endpoints of the study included safety and improvement in clinical activity measured by the CDAI and the Crohn's disease endoscopic index of severity. RESULTS STA 5326 was well tolerated. Reported adverse events were similar across dose cohorts. The most common (>15%) drug-related adverse events observed were dizziness, nausea, headache, and fatigue. Clinical activity at day 28/29 was observed at qd doses of 28 mg and above for the clinical endpoints of response and remission: 70 points or greater decrease in CDAI (range 42%-82% of patients); 100 points or greater decrease in CDAI (range 38%-64% of patients), and CDAI <150 (range 15%-36%). CONCLUSIONS Oral qd dosing of STA 5326 for 4 weeks was well tolerated in doses up to 70 mg qd in patients with active moderate to severe Crohn's disease. Clinical activity was observed at qd doses of 28 mg and above.
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Chey WY, Shah A. Infliximab for ulcerative colitis. J Clin Gastroenterol 2005; 39:920; author reply 920. [PMID: 16208122 DOI: 10.1097/01.mcg.0000180804.49328.69] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
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Chey WD, Chey WY, Heath AT, Dukes GE, Carter EG, Northcutt A, Ameen VZ. Long-term safety and efficacy of alosetron in women with severe diarrhea-predominant irritable bowel syndrome. Am J Gastroenterol 2004; 99:2195-203. [PMID: 15555002 DOI: 10.1111/j.1572-0241.2004.30509.x] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES To assess long-term safety and efficacy of alosetron in women with severe, chronic diarrhea-predominant IBS and in a subset having more frequent urgency (i.e., bowel urgency at least 10 of 14 days during screening). METHODS Randomized patients received either alosetron 1 mg (n = 351) or placebo (n = 363) twice daily during a 48-wk, double-blind study. The primary endpoint was the 48-wk average rate of adequate relief of IBS pain and discomfort. Secondary endpoints included 48-wk average satisfactory control rates of urgency, stool frequency, stool consistency, and bloating. Other efficacy endpoints were average monthly adequate relief and urgency control rates and impact of provided rescue medication. RESULTS Alosetron-treated patients had significantly greater 48-wk average adequate relief (p= 0.01) and urgency control (p < 0.001) rates, regardless of rescue medication use, compared with placebo. Results in subjects with more frequent urgency were more robust than those in the overall population (p= 0.005). In weeks without rescue medication use, satisfactory control rates for stool frequency and stool consistency were significantly greater in alosetron-treated patients than placebo. Alosetron-treated patients had significantly greater adequate relief than placebo-treated patients (p < 0.05) in 9 of 12 months and significantly greater urgency control (p < 0.001) in all months. Adequate relief and urgency control were maintained throughout the treatment. Adverse events and serious adverse events were similar between treatment groups, except for constipation. Neither ischemic colitis nor serious events related to bowel motor dysfunction was reported. CONCLUSIONS Long-term use of alosetron is effective and well-tolerated in women with chronic, diarrhea-predominant IBS, including those with more frequent urgency.
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Affiliation(s)
- William D Chey
- University of Michigan Medical Center, Ann Arbor, Michigan, USA
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Burt RW, Leppert MF, Slattery ML, Samowitz WS, Spirio LN, Kerber RA, Kuwada SK, Neklason DW, Disario JA, Lyon E, Hughes JP, Chey WY, White RL. Genetic testing and phenotype in a large kindred with attenuated familial adenomatous polyposis. Gastroenterology 2004; 127:444-51. [PMID: 15300576 DOI: 10.1053/j.gastro.2004.05.003] [Citation(s) in RCA: 144] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND & AIMS An attenuated form of familial adenomatous polyposis has been described, but the phenotype remains poorly understood. METHODS We performed genetic testing on 810 individuals from 2 attenuated familial adenomatous polyposis kindreds harboring an identical germline adenomatous polyposis coli gene mutation. Colonoscopy was performed on mutation-positive persons. RESULTS The disease-causing mutation was present in 184 individuals. Adenomatous polyps were present in 111 of 120 gene carriers who had colonoscopy at an average age of 41 years. The median number of adenomas was 25 (range, 0-470), with striking variability of polyp numbers and a proximal colonic predominance of polyps. Colorectal cancer occurred in 27 mutation carriers (average age, 58 years; range, 29-81 years), with 75% in the proximal colon. The cumulative risk of colorectal cancer by age 80 was estimated to be 69%. An average of 3.4 recurrent polyps (range, 0-29) were found in the postcolectomy rectal remnant over a mean of 7.8 years (range, 1-34 years), with 1 rectal cancer. CONCLUSIONS This investigation shows that attenuated familial adenomatous polyposis in the kindreds examined shows a much smaller median number of polyps than typical familial adenomatous polyposis, a wide variability in polyp number even at older ages, and a more proximal colonic location of polyps and cancer, yet it is associated with an extremely high risk of colon cancer. The phenotype of attenuated familial adenomatous polyposis mimics typical familial adenomatous polyposis in some cases but in others is difficult to distinguish from sporadic adenomas and colorectal cancer, thus making genetic testing particularly important.
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Affiliation(s)
- Randall W Burt
- Department of Medicine, University of Utah, Salt Lake City, USA.
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Abstract
One hundred years have elapsed since the discovery of secretin by Bayliss and Starling in 1902. In the past century, the research of secretin has gone by many milestones including isolation, purification and structural determination, chemical synthesis, establishment of its hormonal status by radioimmunoassay and immunoneutralization, identification of the specific receptor, cloning of secretin and its receptor, and identification of a secretin-releasing peptide. It has become clear that secretin is a hormone-regulating pancreatic exocrine secretion of fluid and bicarbonate, gastric acid secretion, and gastric motility. The release and actions of secretin is regulated by hormone-hormonal and neurohormonal interactions. The vagus nerve, particularly its afferent pathway, plays an essential role in the physiological actions of secretin. Substantial information about the property of the secretin receptor has been accumulated, but a potent secretin receptor-specific antagonist remains to be formulated. The neural regulatory mechanisms of the release and action of secretin await further elucidation. The physiological role of secretin in intestinal secretions and motility and extragastrointestinal organs remains to be defined. The presence of secretin and its receptor in the central nervous system is well documented, but its function as a neuropeptide has been recognized gradually and requires extensive study in the future.
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Affiliation(s)
- William Y Chey
- Rochester Institute for Digestive Diseases and Sciences, 222 Alexander Street, Suite 3100, Rochester, NY 14607, USA
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Sands BE, Anderson FH, Bernstein CN, Chey WY, Feagan BG, Fedorak RN, Kamm MA, Korzenik JR, Lashner BA, Onken JE, Rachmilewitz D, Rutgeerts P, Wild G, Wolf DC, Marsters PA, Travers SB, Blank MA, van Deventer SJ. Infliximab maintenance therapy for fistulizing Crohn's disease. N Engl J Med 2004; 350:876-85. [PMID: 14985485 DOI: 10.1056/nejmoa030815] [Citation(s) in RCA: 1476] [Impact Index Per Article: 73.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Infliximab, a monoclonal antibody against tumor necrosis factor, is an effective maintenance therapy for patients with Crohn's disease without fistulas. It is not known whether infliximab is an effective maintenance therapy for patients with fistulas. METHODS We performed a multicenter, double-blind, randomized, placebo-controlled trial to evaluate the efficacy of infliximab maintenance therapy in 306 adult patients with Crohn's disease and one or more draining abdominal or perianal fistulas of at least three months' duration. Patients received 5 mg of infliximab per kilogram of body weight intravenously on weeks 0, 2, and 6. A total of 195 patients who had a response at weeks 10 and 14 and 87 patients who had no response were then randomly assigned to receive placebo or 5 mg of infliximab per kilogram every eight weeks and to be followed to week 54. The primary analysis was the time to the loss of response among patients who had a response at week 14 and underwent randomization. RESULTS The time to loss of response was significantly longer for patients who received infliximab maintenance therapy than for those who received placebo maintenance (more than 40 weeks vs. 14 weeks, P<0.001). At week 54, 19 percent of patients in the placebo maintenance group had a complete absence of draining fistulas, as compared with 36 percent of patients in the infliximab maintenance group (P=0.009). CONCLUSIONS Patients with fistulizing Crohn's disease who have a response to induction therapy with infliximab have an increased likelihood of a sustained response over a 54-week period if infliximab treatment is continued every 8 weeks.
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Affiliation(s)
- Bruce E Sands
- Gastrointestinal Unit, Massachusetts General Hospital, and Harvard Medical School, Boston 02114, USA
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Chey WY, Chang TM. Neural control of the release and action of secretin. J Physiol Pharmacol 2003; 54 Suppl 4:105-12. [PMID: 15075453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 11/15/2003] [Accepted: 12/18/2003] [Indexed: 04/29/2023]
Abstract
The release and physiological actions of secretin on pancreatic exocrine secretion and gastric secretion of acid and motility are regulated by neuro-hormonal control. The release of secretin by duodenal acidification is mediated by a secretin releasing peptide (SRP). The release and action of SRP are neurally mediated depending on vagal afferent pathway. SRP activity in acid perfusate of the duodenum was substantially decreased when rats were treated with tetradotoxin (TTX), perivagal application of capsaicin, a beta-adrenergic blocker, Met-enkephalin (MEK) or vagotomy. The release of secretin by SRP was abolished in rats treated with TTX, mucosal or perivagal application of capsaicin, MEK or vagotomy. Both release of secretin and pancreatic exocrine secretion (PES) elicited by duodenal acidification were also inhibited dose-dependently by Met-enkepahlin, 5-HT(2) antagonist, ketanserin and 5-HT(3) antagonist, ondansetron. Stimulation of PES and inhibition of gastric acid secretion and motility by secretin in a physiological dose are also dependent on the vagal afferent pathway as these effects of secretin are abolished by perivagal capsaicin treatment or vagotomy. In conscious rats, vagotomy, vagal ligation, or perivagal colchicine but not capsaicin treatment reduced the number of secretin binding sites in the forestomach suggesting another mode of neural regulation that affects gastric motility. Except in the rat, stimulation of PES by secretin in a physiological dose is profoundly inhibited by atropine indicating the importance of a cholinergic input. In isolated and perfused rat pancreas, electrical field stimulation potentiated secretin-stimulated PES that was suppressed by atropine and anti-GRP serum, suggesting the roles of intrapancreatic cholinergic and GRP-containing neurons. In rats, secretin-stimulated PES was inhibited by a NO synthase inhibitor suggesting mediation by NO. However, the neuropeptides and neurotransmitters involved in regulation of the release and action of secretin and their sites of action remain to be elucidated.
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Affiliation(s)
- W Y Chey
- Rochester Institute for Digestive Diseases and Sciences, Rochester, NY 14607, USA.
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Abstract
We tested the hypothesis that the release of cholecystokinin (CCK) and peptide YY (PYY) may be independent of the region of the small intestine exposed to fat. In five dogs equipped with duodenal and midgut fistulas, the small intestine was compartmentalized so that fat was confined to either the proximal or distal one-half of the gut. Plasma CCK and PYY levels were measured by radioimmunoassay and compared by the square root of the area under the curve (sqrt AUC), representing the plasma peptide concentration over time. CCK was released similarly whether fat was delivered into the proximal (69.9+/-4.7 pM) or distal (71.0+/-5.5 pM) gut, but significantly more CCK (88.9+/-5.6 pM; p<0.05) was released when both the proximal and distal gut were perfused simultaneously with fat. PYY was released similarly whether fat was delivered into the proximal (34.9+/-2.6 pM) or distal (40.0+/-1.2 pM) gut or both (38.6+/-2.2 pM). We conclude that CCK and PYY are released by fat in either the proximal or distal one-half of the small intestine.
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Affiliation(s)
- Henry C Lin
- Department of Medicine, Cedars-Sinai Medical Center, Burns and Allen Research Institute, 8635 W. 3rd Street, #770 W, Los Angeles, CA 90048, USA.
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Chey WY, Chang CH, Pan HJ, Chang C, Kim BM, Park IS, Chang TM. Evidence on the presence of secretin cells in the gastric antral and oxyntic mucosa. Regul Pept 2003; 111:183-90. [PMID: 12609767 DOI: 10.1016/s0167-0115(02)00286-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Secretin is released from upper small intestinal mucosa to drive pancreatic secretion of fluid and bicarbonate and inhibit gastric acid secretion. Recently, we found that, in isolated, vascularly perfused rat stomach model, the inhibition of acid secretion by pituitary adenylate cyclase activating polypeptide (PACAP) was mediated in part via local release of secretin. However, the presence of secretin-producing cells and mRNA in gastric mucosa, particularly in oxyntic mucosa, has not been established. The present study was carried out to establish the presence of secretin cells by immunohistochemical and mRNA by biochemical methods in gastric mucosa. Secretin cells were identified in antral mucosa (27.8 +/- 2.0 cells/mm(2)) and corpus (4.7 +/- 0.5 cells/mm(2)). They were distinguishable, through double immunostaining, from gastrin and somatostatin cells in the antrum and from somatostatin cells in the corpus. The results of reverse transcription (RT)-PCR and Southern blot indicated that a secretin gene transcript of 454 bp was present in the mRNA extracts of both antral and corpus mucosae. The results indicated that secretin mRNA is present in gastric mucosa. In conclusion, secretin-producing cells and mRNA are present in gastric mucosa and the locally released secretin may exert a paracrine effect to inhibit acid secretion.
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Affiliation(s)
- William Y Chey
- Konar Center for Digestive and Liver Diseases, Department of Medicine, University of Rochester Medical Center, Rochester, NY, USA.
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12
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Chey WY. Joy of scientific pursuance and medical practice, an art. Nihon Naika Gakkai Zasshi 2002; 91 Suppl:167-71. [PMID: 12426763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
Affiliation(s)
- William Y Chey
- Rochester Institute for Digestive Diseases and Sciences, USA
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Abstract
Exocrine pancreatic secretion is regulated by hormone-hormonal and neural-hormonal interactions involving several regulatory peptides and neurotransmitter from the gut, the pancreas and the vagus nerve. The roles of the gastrointestinal peptides including secretin, CCK, neurotensin, motilin, PYY and pancreatic islet hormones including insulin, pancreatic polypeptide and somatostatin have been established. Interactions among secretin, CCK and neurotensin produce synergistic stimulatory effect. Motilin modulates the cyclic pattern of pancreatic secretion while local insulin provides a permissive role for the action of secretin and CCK at physiological concentration. Somatostatin, PYY and pancreatic polypeptide are inhibitory regulators, acting either on the release of secretin and CCK or on the action of the two stimulatory hormones. The vagal afferent-efferent pathway mediates the actions of many of these regulatory peptides, particularly of secretin and CCK. Acetylcholine and nitric oxide are the neurotransmitters known to mediate the actions of secretin and CCK. Serotonin (5-HT) released from enterochromaffin cells in the intestinal mucosa and nerve terminals of the enteric nervous system and intrapancreatic nerves may be involved in both stimulatory and inhibitory mechanism through its various receptor subtypes. 5-HT also mediates the action of secretin and CCK. The regulatory roles of neuropeptides, PACP and GRP, are now established, whereas those of others are being uncovered. Pancreatic juice provides both positive and negative feedback regulation of pancreatic secretion through mediation of both secretin- and CCK-releasing peptides. Three CCK-releasing peptides have been purified: monitor peptide from pancreatic juice, diazepam-binding inhibitor from porcine intestine, and luminal CCK-releasing factor from rat intestinal secretion. All have been shown to stimulate CCK release and pancreatic enzyme secretion. Pancreatic phospholipase A2 from pancreatic juice and intestinal secretion appears to function as a secretin-releasing peptide. However, the detailed map of neurohormonal regulatory pathways of exocrine pancreatic secretion is yet to be constructed.
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Affiliation(s)
- W Y Chey
- Rochester Institute for Digestive Diseases and Sciences, 222 Alexander Street, Suite 3100, Rochester, NY 14607, USA.
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Yacyshyn BR, Chey WY, Goff J, Salzberg B, Baerg R, Buchman AL, Tami J, Yu R, Gibiansky E, Shanahan WR. Double blind, placebo controlled trial of the remission inducing and steroid sparing properties of an ICAM-1 antisense oligodeoxynucleotide, alicaforsen (ISIS 2302), in active steroid dependent Crohn's disease. Gut 2002; 51:30-6. [PMID: 12077088 PMCID: PMC1773277 DOI: 10.1136/gut.51.1.30] [Citation(s) in RCA: 175] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND AIMS To evaluate the safety and efficacy of the intercellular adhesion molecule 1 (ICAM-1) antisense phosphorothioate oligonucleotide alicaforsen (ISIS 2302) in Crohn's disease. METHODS Active (Crohn's disease activity index (CDAI) 200-350), steroid dependent (prednisone 10-40 mg) Crohn's patients were randomised into three treatment groups: placebo versus ISIS 2302 (2 mg/kg intravenously three times a week) for two or four weeks. Patients were treated in months 1 and 3, with steroid withdrawal attempted by week 10. The primary end point (steroid free remission) was a CDAI <150 off steroids at the end of week 14. RESULTS A total of 299 patients were enrolled, with a mean baseline CDAI of 276 and steroid dose of 23 mg/day. Rates of steroid free remission were equivalent for the two and four week ISIS 2302 groups (20.2% and 21.2%) and the placebo group (18.8%). At week 14, steroid withdrawal was successful in more ISIS 2302 patients compared with placebo treated patients (78% v 64%; p=0.032). Steroid free remission was highly correlated with exposure (p=0.0064). Other clinical responses were correlated with exposure, with significant results versus placebo being observed in the highest area under the curve subgroup. CDAI scores decreased by 136 (112) at week 14 versus 52 (107) for placebo (p=0.027) and inflammatory bowel disease score questionnaire improved by 43 (31) versus 15 (36) for placebo (p=0.027). CONCLUSIONS Although the primary outcomes failed to demonstrate efficacy, pharmacodynamic modelling suggests that alicaforsen (ISIS 2302) may be an effective therapy for steroid dependent Crohn's disease.
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Affiliation(s)
- B R Yacyshyn
- Division of Gastroenterology, University of Alberta, Edmonton, Alberta, Canada.
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16
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Abstract
OBJECTIVE The most important goal in the management of photosensitive drug eruptions, as in other types of drug eruptions is identification of the causative drugs to prevent reexposure to them. CASE SUMMARIES Seven patients whose lesions were mainly distributed on sun-exposed areas underwent laboratory tests, phototests, and photopatch tests with suspected drugs. Phototests were done with ultraviolet A (UVA), UVB, and visible light. Drugs used in the photopatch tests were usually prepared as 10% concentrations in petroleum base, which did not produce reactions in 10 control subjects, followed by irradiation of suberythema doses of UVA. Systemic provocation by oral administration of small doses of causative drugs with irradiation of suberythema doses of UVA was performed to confirm the results of skin tests in four patients. Two patients were not rechallenged with the causative drugs. None of the patients had systemic lupus erythematosus, porphyria, or pellagra. All showed positive reactions to photopatch testing. Systemic provocation confirmed the results of photopatch tests in four patients. The two patients who were not rechallenged had no recurrence of lesions. One patient ingested only one drug at the time of eruptions, and provocation or avoidance was not attempted. A photoallergic mechanism was considered in five cases. CONCLUSIONS Although there is no information about the appropriate concentrations or vehicles for suspected drugs, photopatch testing could be reliable for identification of causes of photosensitive drug eruptions. Besides piroxicam (a well-known photosensitizer) and carbamazepine, isoniazid and triflusal were identified as the causes of the reactions.
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Affiliation(s)
- A Y Lee
- Department of Dermatology, Eulji Hospital University of Medicine, 280-1, Hagye-1-dong, Nowon-gu, Seoul 139-711, South Korea.
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17
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Abstract
The exocrine pancreas is regulated by various hormonal factors derived from the gut through hormone-hormonal and neurohormonal interactions. Physiologic stimuli entering the upper small intestine elicit the release of intestinal hormones and activate sensory reflex mechanisms from the intestinal mucosa to stimulate or inhibit exocrine pancreatic secretion. In addition, the endocrine pancreas, intrapancreatic nerves, and some extrapancreatic neural pathways, with or without mediation by the vagus nerve, are known to participate in regulation of exocrine pancreatic secretion. It has been established that two key intestinal hormones, secretin and cholecystokinin (CCK), in physiologic doses, act through the vagal afferent pathway and interact with each other as well as with other gut hormones. The releases of these two hormones are mediated through the corresponding releasing peptides. In the past few years, the roles of secretin- and CCK-releasing peptides have become more clearly defined. The participation of several neurotransmitters and regulatory peptides in the regulation of exocrine pancreatic secretion has also been established. In addition, neurotransmitters and neuropeptides released from the central nervous system may participate in the regulation of pancreatic secretion. It is conceivable that a few neurotransmitters and neuropeptides are involved in each neural regulatory pathway. However, their roles and sites of action in each pathway remain to be determined.
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Affiliation(s)
- T M Chang
- Rochester Institute for Digestive Diseases and Sciences, Rochester, New York 14607, USA
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18
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Abstract
Eight patients with active ulcerative colitis (UC), refractory to usual combination medical therapy, were treated with a single i.v. dose of chimeric monoclonal antibody to recombinant human tumor necrosis factor alpha; many of these patients were scheduled for surgical colectomy because of their active disease. All patients responded extremely well to a single 5 mg/kg infusion of infliximab, with marked improvement after the infusion clinically, colonoscopically, and histologically on colonic biopsy. There were no significant complications or side effects; mean duration of remission has not been determined because none of the patients have relapsed. Infliximab appears to be a potent agent for inducing remission in refractory patients with ulcerative colitis.
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Affiliation(s)
- W Y Chey
- Konar Center for Digestive and Liver Diseases, Rochester, New York, USA
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Abstract
A secretin-releasing activity exists in the upper small intestine and pancreatic juice in the rat and the dog. Group I pancreatic phospholipase A2 (PLA2) in canine pancreatic juice and porcine pancreatic PLA2 stimulate the release of secretin from both STC-1 cells and a secretin-producing cell (S cell)-enriched preparation isolated from rat duodenal mucosa. We investigated the distribution and release of pancreatic PLA2-like immunoreactivity in the gastrointestinal tract and the role of PLA2 on the release of secretin and pancreatic exocrine secretion in response to duodenal acidification in anesthetized rats. PLA2-like immunoreactivity was detected in the mucosa throughout the gastrointestinal tract. High concentrations of PLA2 were found in both the small intestine and the pancreas. Duodenal acidification significantly increased the release of PLA2 from the upper small intestine (385% over basal secretion). Intravenous infusion of an anti-PLA2 serum (anti-PLA2) dose-dependently inhibited the release of secretin and pancreatic exocrine secretion in response to duodenal acid perfusion. Preincubation of the concentrate of intestinal acid perfusate (10-fold) from donor rats with the anti-PLA2 significantly suppressed its stimulation of secretin release and pancreatic exocrine secretion in recipient rats. We conclude that pancreatic PLA2 also functions as a secretin-releasing factor in the small intestine that mediates acid-stimulated release of secretin in rats.
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Affiliation(s)
- J P Li
- Konar Center for Digestive and Liver Diseases, University of Rochester Medical Center, Rochester, New York 14624, USA
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20
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Camilleri M, Chey WY, Mayer EA, Northcutt AR, Heath A, Dukes GE, McSorley D, Mangel AM. A randomized controlled clinical trial of the serotonin type 3 receptor antagonist alosetron in women with diarrhea-predominant irritable bowel syndrome. Arch Intern Med 2001; 161:1733-40. [PMID: 11485506 DOI: 10.1001/archinte.161.14.1733] [Citation(s) in RCA: 245] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
BACKGROUND Irritable bowel syndrome (IBS) is a common gastrointestinal disorder seen in primary care practice. The symptoms of IBS, including abdominal pain, discomfort, and abnormal bowel function, may be modulated by activity of the serotonin type 3 receptor (5-HT(3)). The efficacy and tolerability of the 5-HT(3) receptor antagonist alosetron hydrochloride in nonconstipated female patients with IBS were evaluated in a double-blind, randomized, placebo-controlled trial. METHODS Patients received either 1 mg of alosetron hydrochloride (n = 309) or placebo (n = 317) twice daily for 12 weeks, followed by a 4-week posttreatment period. Adequate relief of IBS pain and discomfort was the primary end point. Secondary end points included improvements in urgency, stool frequency, stool consistency, incomplete evacuation, and bloating. RESULTS Seventy-one percent of patients were classified as having diarrhea-predominant IBS. Forty-three percent of alosetron-treated patients with diarrhea-predominant IBS reported adequate relief for all 3 months compared with 26% of placebo-treated patients (P<.001; percentage point difference = 17; 95% confidence interval, 8.0-25.4). Improvement with alosetron compared with placebo was observed by the end of the fourth week of treatment and persisted throughout the remainder of treatment. Alosetron significantly decreased urgency and stool frequency and caused firmer stools within 1 week of starting treatment. Effects were sustained throughout treatment and symptoms returned following treatment cessation. No significant improvement in the percentage of days with sense of incomplete evacuation or bloating was observed compared with placebo during the first month of treatment. Constipation was the most commonly reported adverse event. CONCLUSION Alosetron hydrochloride, 1 mg twice daily for 12 weeks, is effective in relieving pain and some bowel-related symptoms in diarrhea-predominant female patients with IBS.
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Affiliation(s)
- M Camilleri
- Glaxo Wellcome Inc, 5 Moore Dr, Research Triangle Park, NC 27709, USA
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21
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Abstract
We investigated the mechanism of action of methionine enkephalin (MEK) on HCl-stimulated secretin release and pancreatic exocrine secretion. Anesthetized rats with pancreatobiliary cannulas and isolated upper small intestinal loops were perfused intraduodenally with 0.01 N HCl while bile and pancreatic juice were diverted. The effect of intravenous MEK on acid-stimulated secretin release and pancreatic exocrine secretion was then studied with or without coinfusion of naloxone, an anti-somatostatin (SS) serum, or normal rabbit serum. Duodenal acid perfusate, which contains secretin-releasing peptide (SRP) activity, was collected from donor rats with or without pretreatment with MEK, MEK + naloxone, or MEK + anti-SS serum, concentrated by ultrafiltration, and neutralized. The concentrated acid perfusate (CAP), which contains SRP bioactivity, was infused intraduodenally into recipient rats. MEK increased plasma SS concentration and inhibited secretin release and pancreatic fluid and bicarbonate secretion dose-dependently. The inhibition was partially reversed by naloxone and anti-SS serum but not by normal rabbit serum. In recipient rats, CAP increased plasma secretin level and pancreatic secretion. CAP SRP bioactivity decreased when it was collected from MEK-treated donor rats; this was partially reversed by coinfusion with naloxone or anti-SS serum. These results suggest that in the rat, MEK inhibition of acid-stimulated pancreatic secretion and secretin release involves suppression of SRP activity release. Thus the MEK inhibitory effect appears to be mediated in part by endogenous SS.
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Affiliation(s)
- J P Li
- Konar Center for Digestive and Liver Diseases, University of Rochester Medical Center, Rochester, NY 14642, USA
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22
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Abstract
Conventional treatment options for patients with severe corticosteroid-refractory ulcerative colitis (UC) include intravenous cyclosporine, which is frequently limited by toxicity, or colectomy. The efficacy of infliximab was investigated in the treatment of 16 patients with severely active UC refractory to conventional therapy; 7 of these patients were considered for colectomy pending medical failure. All patients received a single infusion of infliximab, 5 mg/kg; 6 of 16 patients (38%) received a second infusion approximately 5 months later. Efficacy was assessed by clinical response (defined as the lack of symptoms) as well as endoscopic and histologic outcomes. Clinical, endoscopic, and histologic improvement was observed in 14 of 16 patients (88%) after treatment with infliximab. Surgery was avoided in six of seven surgical candidates (86%). Clinical remission was maintained in 14 of 16 patients (88%) for > or = 4 months, and 4 of 16 patients (25%) for 7-10 months. Most of the treated patients were completely withdrawn from corticosteroid therapy. Treatment with infliximab induced endoscopic remission at 30 days and a significant improvement from baseline in mean histologic score (p < 0.001). In conclusion, infliximab improved clinical, endoscopic, and histologic outcomes in patients with severely active UC refractory to conventional therapy, allowing corticosteroid sparing and reducing the need for colectomy.
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Affiliation(s)
- W Y Chey
- Rochester Institute for Digestive Disease and Sciences, New York 14607, USA
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23
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Abstract
OBJECTIVES Although colon dysmotility is recognized as a pathophysiological factor in irritable bowel syndrome (IBS), it has not been characterized. We have investigated motility patterns in IBS patients with abdominal pain and frequent defecation or diarrhea and in healthy volunteers. METHODS A recording catheter that had six polyvinyl tubes with infusion ports was placed in the transverse, descending, and sigmoid colon under fluoroscopy. After 2-h basal recordings, motility responses to cholecystokinin octapeptide (CCK-8) and a meal were studied for 3 h. The motility index (MI) and number of high amplitude propagating contractions (HAPCs) in 10 IBS patients were compared with those of 10 controls. HAPCs were correlated with abdominal pain, and colon transit time using radio-opaque markers was determined. Using human colon muscle strips, the effect of CCK-8 on muscle contractions was also studied. RESULTS The MI and mean number and peak amplitude of HAPCs in IBS patients were significantly greater than in controls. These abnormalities paralleled markedly shortened colonic transit time. Abdominal pain coincided with >90% of HAPCs. Dose-dependent muscle contraction by CCK-8 was profoundly suppressed both by loxiglumide and atropine. CONCLUSIONS The dysmotility in this subset of IBS patients was characterized by significantly increased occurrences of powerful HAPCs that paralleled rapid colon transit and were accompanied by abdominal pain. Thus, it is suggested that this powerful contraction is one of the causes of abdominal pain. The action of CCK-8 seems to be mediated via the colon enteric nervous system.
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Affiliation(s)
- W Y Chey
- Rochester Institute for Digestive Diseases and Sciences, University of Rochester Medical Center, New York 14607, USA
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24
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Abstract
5-Hydroxytryptamine (serotonin, 5-HT) is a hormone and neurotransmitter regulating gastrointestinal functions. 5-HT receptors are widely distributed in gastrointestinal mucosa and the enteric nervous system. Duodenal acidification stimulates not only the release of both 5-HT and secretin but also pancreatic exocrine secretion. We investigated the effect of 5-HT receptor antagonists on the release of secretin and pancreatic secretion of water and bicarbonate induced by duodenal acidification in anesthetized rats. Both the 5-HT(2) receptor antagonist ketanserin and the 5-HT(3) receptor antagonist ondansetron at 1-100 microg/kg dose-dependently inhibited acid-induced increases in plasma secretin concentration and pancreatic exocrine secretion. Neither the 5-HT(1) receptor antagonists pindolol and 5-HTP-DP nor the 5-HT(4) receptor antagonist SDZ-205,557 affected acid-evoked release of secretin or pancreatic secretion. None of the 5-HT receptor antagonists affected basal pancreatic secretion or plasma secretin concentration. Ketanserin or ondansetron at 10 microg/kg or a combination of both suppressed the pancreatic secretion in response to intravenous secretin at 2.5 and 5 pmol x kg(-1) x h(-1) by 55-75%, but not at 10 pmol x kg(-1) x h(-1). Atropine (50 microg/kg) significantly attenuated the inhibitory effect of ketanserin on pancreatic secretion but not on the release of secretin. These observations suggest that 5-HT(2) and 5-HT(3) receptors mediate duodenal acidification-induced release of secretin and pancreatic secretion of fluid and bicarbonate. Also, regulation of pancreatic exocrine secretion through 5-HT(2) receptors may involve a cholinergic pathway in the rat.
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Affiliation(s)
- J P Li
- Konar Center for Digestive and Liver Diseases, School of Medicine and Dentistry, University of Rochester, Rochester, New York 14642, USA
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25
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Wolfe SG, Chey WY, Washington MK, Harding J, Heath AT, McSorley DJ, Dukes GE, Hunt CM. Tolerability and safety of alosetron during long-term administration in female and male irritable bowel syndrome patients. Am J Gastroenterol 2001; 96:803-11. [PMID: 11280555 DOI: 10.1111/j.1572-0241.2001.03626.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Alosetron (Lotronex) is a new therapeutic agent for irritable bowel syndrome (IBS) in women with diarrhea-predominant IBS. This multicenter randomized, double-blind, placebo-controlled study assessed the safety and tolerability of alosetron during long-term (< or = 12 months) treatment. METHODS A total of 859 subjects (637 female and 222 male) with IBS were enrolled from 130 sites in the United States and were randomized 3:1 to receive 1 mg alosetron or placebo b.i.d. for 48 wk; of the subjects, 649 (76%) were randomized to the alosetron group and 212 (24%) to the placebo group. Of the original group, 850 subjects received at least one dose of alosetron (n = 640) or placebo (n = 210). RESULTS In all, 59% of the subjects completed the study. Safety data were similar in treatment groups and within age, sex, racial origin, and hormone use. Adverse events were reported by 83% (530/640) and 76% (159/210) of subjects in the alosetron and placebo groups, respectively, (p < 0.05) and were similar with the exception of constipation; 32% of subjects receiving alosetron reported constipation, compared to 5% in the placebo group (p < 0.001). Most reports (72%) of constipation were of mild or moderate severity, and 66% of subjects with constipation had single episode of 8 days median duration. Constipation occurred a median of 13 days after initiating treatment and resolved spontaneously, with laxative, or after a brief interruption of therapy. Of the subjects, 4% (11/210) in the alosetron and 5% (28/ 640) in the placebo group experienced serious adverse events. Two deaths occurred in subjects with pre-existing cardiovascular risk factors; neither death was attributed to the study drug. CONCLUSIONS Alosetron 1 mg b.i.d. for 12 months was well tolerated. Constipation is the most frequent adverse event, with a higher incidence of transient constipation in alosetron-treated patients, typically occurring in the first month of treatment.
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Affiliation(s)
- S G Wolfe
- Gastroenterology Clinical Development, Glaxo Wellcome, Research Triangle Park, North Carolina, USA
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26
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Abstract
We tested the hypothesis that the release of PYY by fat confined to the proximal small intestine is dependent on CCK. Using a multi-fistulated model, plasma PYY levels were compared in 6 dogs after 60 mM oleate was perfused into the proximal one-half of the small intestine following i.v. administration of saline or devazepide, a CCK-A antagonist. Plasma PYY increased with fat (P < 0. 05), but plasma PYY level was lower following devazepide at 60 min and 90 min (P < 0.05). We conclude that CCK serves as a foregut signal linking fat in the proximal gut with the release of distal gut PYY.
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Affiliation(s)
- H C Lin
- Department of Medicine, Burns & Allen Research Institute, Cedars-Sinai Medical Center, Los Angeles, California 90048, USA.
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27
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Abstract
Long-chain fatty acids are potent stimulants of secretin and CCK release. The cellular mechanisms of fatty acid-stimulated secretion of these two hormones are not clear. We studied the stimulatory effect and mechanism of sodium oleate (SO) on secretin- and CCK-producing cells. SO stimulated the release of secretin or CCK from isolated rat mucosal cell preparations enriched in either secretin- or CCK-producing cells, respectively. SO also time- and dose-dependently stimulated secretin and CCK release from STC-1 cells. In STC-1 cells, SO-stimulated secretin and CCK release was potentiated by IBMX and inhibited by a protein kinase A-selective inhibitor and a cAMP-specific antagonist. SO-stimulated releases of the two hormones were also inhibited by downregulation or inhibitors of protein kinase C, a calmodulin antagonist and an inhibitor of calmodulin-dependent protein kinase II. Chelating of extracellular Ca(2+) or addition of an L-type calcium channel blocker diminished SO-stimulated hormone releases. SO caused an increase in intracellular Ca(2+) concentration that was partially reversed by diltiazem but had no effect on production of cAMP, cGMP, or inositol-1,4,5-triphosphate. These results indicate that SO acts on secretin- and CCK-producing cells. Its stimulatory effect is potentiated by endogenous protein kinase A and mediated by activation of Ca(2+) influx through the L-type channels and of protein kinase C and Ca(2+)/calmodulin-dependent protein kinase II.
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Affiliation(s)
- C H Chang
- Konar Center for Digestive and Liver Diseases, Department of Medicine, University of Rochester School of Medicine and Dentistry, New York 14642, USA
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28
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Abstract
This case details the development of a rapidly growing polypoid mass in the proximal stomach in a patient with known attenuated familial adenomatous polyposis. Surgical resection was required and histology showed hyperplasia with extensive areas of dysplastic adenomatous change. This case illustrates that patients with the attenuated form of familial adenomatous polyposis are at risk for multiple neoplasia distinct from those patients with the classic form of familial adenomatous polyposis.
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Affiliation(s)
- T J McGarrity
- Department of Medicine, The Milton S. Hershey Medical Center, The Pennsylvania State University College of Medicine, 17033, USA
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29
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Abstract
Nitric oxide (NO) is one of the important biologic mediators in regulation of gastrointestinal (GI) functions, but the influence of NO on the release of secretin and cholecystokinin (CCK) and exocrine pancreatic secretion has not been adequately investigated in the rat. The aim of this study was to determine the role of NO on endogenous and exogenous secretin- or CCK-stimulated pancreatic exocrine secretion both in anesthetized and conscious rats. Experiments were carried out in four different groups of rats with duodenal pancreatobiliary cannulas and jugular vein catheters. Group 1: During duodenal infusion of 0.05N HCl or 15% casein (pH 7.0), N-nitro-L-arginine (NNA), an inhibitor of NO-synthase in graded doses (2.5, 5, 10 mg/kg/h), was infused intravenously. Group 2: One hour after starting intravenous secretin at 5 pmol/kg/h or intravenous CCK-8 at 0.06 microg/kg/h, NNA in graded doses was administered intravenously. Group 3: In conscious rats, NNA (5 mg/kg/h) was given intravenously for 1 hour after a meal. Group 4: L-Arginine at 100 mg/kg/h was infused intravenously during the period of NNA (5 mg/kg/h) infusion in groups 1, 2, and 3. Pancreatic juice was collected at 30-minute intervals to measure volume, as well as output of bicarbonate and protein. At the end of the experiment, plasma secretin, vasoactive intestinal polypeptide (VIP) and CCK levels were determined by radioimmunoassay (RIA). NNA dose dependently inhibited the pancreatic secretion of fluid and bicarbonate stimulated by duodenal acidification, exogenous secretin, and a meal. NNA dose dependently inhibited the pancreatic secretion of protein stimulated by duodenal infusion of casein, exogenous CCK, and a meal. L-Arginine significantly reversed the NNA-induced inhibition of pancreatic secretion in all experiments. NNA did not alter significantly the plasma levels of secretin, VIP, and CCK. Our results indicated that endogenous NO plays a significant role in the regulation of pancreatic exocrine secretion stimulated by secretin and CCK. However, NO does not influence the release of secretin, VIP, or CCK in the rat.
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Affiliation(s)
- S Jyotheeswaran
- W. B. Konar Center for Digestive and Liver Diseases, University of Rochester Medical Center, New York 14642, USA
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30
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Abstract
Effects of intrapancreatic gastrin-releasing peptide (GRP)-containing neurons on secretin-induced pancreatic secretion were investigated in the totally isolated perfused rat pancreas. Electrical field stimulation (EFS) increased secretin (12 pM)-induced pancreatic secretions of fluid and amylase. EFS induced a twofold increase in GRP concentration in portal effluent, which was completely inhibited by tetrodotoxin but not modified by atropine. An anti-GRP antiserum inhibited the EFS-enhanced secretin-induced secretions of fluid and amylase by 12 and 43%, respectively, whereas a simultaneous infusion of the antiserum and atropine completely abolished them. Exogenous GRP dose-dependently increased the secretin-induced pancreatic secretion with an additive effect on fluid secretion and a potentiating effect on amylase secretion, which was not affected by atropine. In conclusion, excitation by EFS of GRPergic neurons in the isolated rat pancreas results in the release of GRP, which exerts an additive effect on fluid secretion and a potentiating effect on amylase secretion stimulated by secretin. The release and action of GRP in the rat pancreas are independent of cholinergic tone.
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Affiliation(s)
- H S Park
- Department of Physiology, College of Medicine, Hallym University, Chunchon, Kangwon-Do, 200-702, Republic of Korea
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31
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Abstract
Canine pancreatic juice has been shown to stimulate exocrine pancreatic secretion in the dog. In the present study we investigated whether there is a secretin-releasing peptide in canine pancreatic juice. Pancreatic juice was collected from the dogs with Thomas gastric and duodenal cannulas while pancreatic secretion was stimulated by intravenous administration of secretin at 0.5 microg/kg/h and CCK-8 at 0.2 microg/kg/h, respectively. The pancreatic juice was separated into three different molecular weight (MW) fractions (Fr) by ultrafiltration (Fr 1; MW > 10,000, Fr 2; MW=10,000-4,000 and Fr 3; MW < 4,000), respectively. All the fractions were bioassayed in anesthetized rats. Fraction 3 dose-dependently and significantly stimulated pancreatic juice flow volume from 78.0% to 99.4% (p<0.05) and bicarbonate output from 128.9% to 202.1% (p<0.01), respectively. Plasma secretin concentration also increased from 1.2 +/- 0.5 pM to 5.0 +/- 0.8 pM and 6.0 +/- 1.0 pM (p<0.05). None of these fractions increased pancreatic protein secretion or plasma CCK level. The stimulatory effect of Fraction 3 on pancreatic secretion and the release of secretin was completely abolished by treatment with trypsin (1 mg/ml for 60 min at 37 degrees C) but not by heating (100 degrees C, 10 min). Intravenous injection of a rabbit anti-secretin serum, which rendered plasma secretin almost undetectable in rat plasma, also abolished Fr 3-stimulated pancreatic secretion of fluid and bicarbonate secretion. These observations suggest that a secretin-releasing peptide exists in the canine pancreatic juice. It is trypsin-sensitive and heat-resistant. This peptide may play a significant physiological role on the release of secretin and regulation of exocrine pancreatic secretion.
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Affiliation(s)
- P Li
- The William and Sheila Konar Center for Digestive and Liver Diseases, University of Rochester Medical Center, NY 14642, USA
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32
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Chang TM, Thagesen H, Lee KY, Roth FL, Chey WY. Canine vagus nerve stores cholecystokinin-58 and -8 but releases only cholecystokinin-8 upon electrical vagal stimulation. Regul Pept 2000; 87:1-7. [PMID: 10710281 DOI: 10.1016/s0167-0115(99)00090-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Cholecystokinin-58 has been shown to be the major form of cholecystokinin (CCK) released to the circulation upon lumenal stimulation of the small intestine in humans and dogs. In anesthetized dogs, electrical vagal stimulation evokes pancreatic exocrine secretion that is in part mediated through the release of CCK. We studied the molecular form of CCK stored in canine vagus nerves and that released into circulation upon electrical vagal stimulation. Gel filtration and radioimmunoassay of the water and acid extracts of canine vagus nerves indicated CCK-8 (35%) and CCK-58 (65%) as the major molecular forms in the vagus nerve. Both forms of CCK isolated from the vagal extracts were equally bioactive as the standard CCK-8 and CCK-58, respectively, in stimulation of amylase release from isolated rat pancreatic acini. Analysis of plasma collected after electrical vagal stimulation indicated that CCK-8 is the only form released into the circulation. The release of CCK-8 upon electrical vagal stimulation was not affected by application of lidocaine to the upper small intestinal mucosa, suggesting that it was released from vagal nerve terminals.
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Affiliation(s)
- T M Chang
- Konar Center for Digestive and Liver Diseases, Department of Medicine, University of Rochester School of Medicine and Dentistry, NY 14642, USA.
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33
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Abstract
Pituitary adenylate cyclase-activating polypeptide (PACAP), existing in two variants, PACAP-27 and PACAP-38, is found in the enteric nervous system and regulates function of the digestive system. However, the regulatory mechanism of PACAP on gastric acid secretion has not been well elucidated. We investigated the inhibitory action of PACAP-27 on acid secretion and its mechanism in isolated vascularly perfused rat stomach. PACAP-27 in four graded doses (5, 10, 20, and 50 microg/h) was vascularly infused to determine its effect on basal and pentagastrin (50 ng/h)-stimulated acid secretion. To study the inhibitory mechanism of PACAP-27 on acid secretion, a rabbit antisecretin serum, antisomatostatin serum, or indomethacin was administered. Concentrations of secretin, somatostatin, PGE(2), and histamine in portal venous effluent were measured by RIA. PACAP-27 dose-dependently inhibited both basal and pentagastrin-stimulated acid secretion. PACAP-27 at 10 microg/h significantly increased concentrations of secretin, somatostatin, and PGE(2) in basal or pentagastrin-stimulated state. The inhibitory effect of PACAP-27 on pentagastrin-stimulated acid secretion was reversed 33% by an antisecretin serum, 80.0% by an antisomatostatin serum, and 46.1% by indomethacin. The antisecretin serum partially reduced PACAP-27-induced local release of somatostatin and PGE(2). PACAP-27 at 10 microg/h elevated histamine level in portal venous effluent, which was further increased by antisomatostatin serum. However, antisomatostatin serum did not significantly increase acid secretion. It is concluded that PACAP-27 inhibits both basal and pentagastrin-stimulated gastric acid secretion. The effect of PACAP-27 is mediated by local release of secretin, somatostatin, and PGE(2) in isolated perfused rat stomach. The increase in somatostatin and PGE(2) levels in portal venous effluent is, in part, attributable to local action of the endogenous secretin.
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Affiliation(s)
- P Li
- Konar Center for Digestive and Liver Diseases, University of Rochester Medical Center, Rochester, New York 14642, USA
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34
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Abstract
We previously showed that canine pancreatic juice contains a secretin-releasing factor activity. In this study, we carried out isolation of two secretin-releasing peptides (SRPs) from canine pancreatic juice. Through ultrafiltration, anion and cation exchange, and reverse-phase high-performance liquid chromatography (HPLC) steps and an in vitro bioassay in STC-1 cells, two SRPs, SRP-1 and SRP-2, were isolated and purified to homogeneity. Both SRPs dose-dependently stimulated secretin release from STC-1 cells. The results of mass spectral analysis indicated that SRP-1 and SRP-2 had molecular masses of 14,061 Da and 14,053 Da, respectively. N-terminal amino acid sequence analysis indicated that SRP-1 was identical to canine pancreatic PLA2 in the 25 residues determined; whereas SRP-2 had 71% sequence homology to the enzyme in the first 21 residues. Commercially available porcine pancreatic PLA2 dose-dependently stimulated secretin release from STC-1 cells. Porcine pancreatic PLA2 also stimulated secretin release from a secretin-producing cells-enriched preparation isolated from rat duodenal mucosa. These results suggest that pancreatic PLA2 and its related peptide may participate in regulation of secretin secretion.
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Affiliation(s)
- T M Chang
- Konar Center for Digestive and Liver Diseases, Department of Medicine, University of Rochester School of Medicine and Dentistry, New York 14642, USA.
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35
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Abstract
A secretin-releasing factor (SRF) was found in canine pancreatic juice that increases plasma secretin and stimulates pancreatic secretion in rats, suggesting that a positive feedback mechanism may be involved in the regulation of pancreatic secretion. In the present study, we investigated to determine whether or not SRF releases endogenous secretin and stimulates exocrine pancreatic secretion in conscious dogs. Fresh pancreatic juice was collected from four dogs by intravenous administration of secretin at 0.5 microg. kg(-1). h(-1) and CCK at 0.2 microg. kg(-1). h. The juice was boiled for 10 min at 100 degrees C. Experiments were carried out in phase I of spontaneous cycle of interdigestive pancreatic secretion. The testing solutions were infused intraduodenally in separate experiments: NaHCO3 solution (0.1 M, 4.5 ml/min, 60 min), a corn oil (Lipomul, 2 ml/min, 10 min), boiled pancreatic juice (BPJ, 4.5 ml/min, 60 min), and mixture of BPJ and Lipomul. Pancreatic secretion of fluid and bicarbonate was significantly increased by either BPJ or a mixture of BPJ and Lipomul (34- and 31-fold or 41- and 38-fold, respectively). Plasma secretin level also significantly increased by 164.7 +/- 13.4% and 223.1 +/- 35.0%, respectively, from basal concentration of 1.7 +/- 0.5 pM. In contrast, neither bicarbonate solution nor Lipomul influenced the plasma secretin level or pancreatic secretion. In addition, when Lipomul was incubated with BPJ, no fatty acid was produced. Thus the increased pancreatic secretion in the dog infused with a combination of BPJ and Lipomul was caused by SRF in BPJ, which released endogenous secretin. Moreover, the increases by BPJ of both plasma secretin level and bicarbonate secretion were completely blocked by intravenous administration of an antisecretin antibody in these dogs. The observations suggest that SRF in pancreatic juice exerts a positive feedback effect on exocrine pancreatic secretion that is mediated by the release of secretin in the interdigestive state in dogs.
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Affiliation(s)
- Y Song
- The William B. and Sheila Konar Center for Digestive and Liver Diseases, University of Rochester Medical Center, Rochester, New York 14642, USA
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36
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Hofgärtner WT, Thorp M, Ramus MW, Delorefice G, Chey WY, Ryan CK, Takahashi GW, Lobitz JR. Gastric adenocarcinoma associated with fundic gland polyps in a patient with attenuated familial adenomatous polyposis. Am J Gastroenterol 1999; 94:2275-81. [PMID: 10445562 DOI: 10.1111/j.1572-0241.1999.01312.x] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Familial adenomatous polyposis (FAP) is a rare autosomal dominant precancerous condition of the colon caused by mutations in the adenomatous polyposis coli (APC) tumor suppressor gene. FAP is characterized by the appearance of innumerable adenomatous polyps throughout the large bowel. Fundic gland polyps are the most common gastric lesion in FAP. It is generally believed that fundic gland polyps have little or no potential for malignant transformation in the population at large, and only a few case reports describe the development of high grade dysplasia or gastric adenocarcinoma associated with diffuse fundic gland polyposis in patients with FAP. We report the second case of gastric adenocarcinoma intimately associated with fundic gland polyposis in a family with an attenuated form of FAP. The patient had undergone routine screening per current guidelines because of his known mutation in the APC gene. This suggests that malignant transformation of fundic gland polyps in patients with FAP occur more frequently than previously believed. Current screening recommendations may not be sufficient for patients with FAP or its attenuated forms.
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Affiliation(s)
- W T Hofgärtner
- Department of Medicine, Providence St. Vincent Medical Center, Portland, Oregon, USA
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37
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Abstract
We have isolated, from canine pancreatic juice, two 14-kDa proteins with secretin-releasing activity that had N-terminal sequence homology with canine pancreatic phospholipase A2 (PLA2). In this study we have obtained evidence that secretin-releasing activity is an intrinsic property of pancreatic PLA2. Porcine pancreatic PLA2 from Sigma or Boehringer Mannheim was fractionated into several peaks by reverse phase high performance liquid chromatography. They were tested for stimulation of secretin release from murine neuroendocrine intestinal tumor cell line STC-1 and secretin cells enriched mucosal cell preparations isolated from rat upper small intestine. Each enzyme preparation was found to contain several components of secretin-releasing activity. Each bioactive fraction was purified to homogeneity by rechromatography and then subjected to mass spectral analysis and assays of PLA2 and secretin-releasing activities. It was found that the fraction with highest enzymatic activity also had the highest secretin-releasing activity and the same Mr as porcine pancreatic PLA2. Moreover, it also had the same N-terminal amino acid sequence (up to 30 residues determined) as that of porcine pancreatic PLA2, suggesting that it was identical to the enzyme. Purified porcine pancreatic PLA2 also stimulated secretin release concentration-dependently from both STC-1 cells and a mucosal cell preparation enriched in secretin-containing endocrine cells isolated from rat duodenum. Abolishment of the enzymatic activity by pretreatment with bromophenacyl bromide did not affect its secretin-releasing activity. The stimulatory effect of purified pancreatic PLA2 on secretin secretion from STC-1 cells was inhibited by an L-type Ca2+ channel blocker, by down-regulation of protein kinase C or by pretreatment of the cell with pertussis toxin. It is concluded that porcine pancreatic PLA2 possesses an intrinsic secretin-releasing activity that was independent of its enzymatic activity. This action is pertussis toxin-sensitive and is in part dependent on Ca2+ influx through the L-type channel and activation of protein kinase C.
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Affiliation(s)
- T M Chang
- Konar Center for Digestive and Liver Diseases, Department of Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642, USA.
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Abstract
Secretin is well known for its inhibitory action on gastric motility. It has been reported that secretin in a physiological dose inhibits gastric motility through mediation by the vagal afferent pathway. Secretin also elicited relaxation of carbachol-stimulated rat forestomach muscle strips by binding to its receptors, suggesting a direct action on this peripheral tissue. We hypothesized that vagal input may affect the action of secretin by modulating the level of secretin receptor in the forestomach. Several treatments, including vagal ligation, vagotomy, perivagal application of capsaicin or colchicine, intravenous infusion of tetrodotoxin, and intraperitoneal injection of atropine, were performed to investigate their effects on secretin receptor binding to forestomach membranes. Specific binding of 125I-labeled secretin to forestomach membranes was significantly decreased (45%) by vagal ligation, vagotomy (50%), or perivagal colchicine treatment (40%). On the contrary, specific binding of 125I-secretin was not affected by perivagal capsaicin treatment, intravenous infusion of tetrodotoxin, or intraperitoneal injection of atropine. By Scatchard analysis of the binding data, the capacity of the high-affinity binding sites in forestomach membranes was found to decrease significantly after vagal ligation compared with membranes from the sham-operated group. However, the affinity at the high-affinity binding sites, the binding parameters of the low-affinity binding sites, and binding specificity were not changed. Vagal ligation but not perivagal capsaicin treatment reduced the inhibitory effect of secretin on bethanechol-stimulated contraction of isolated forestomach muscle strips, causing a right shift in the dose-response curve. These results suggest that vagal input through axonal transport plays a significant role on secretin action by modulating the capacity of secretin binding sites (but not affinity or specificity), at least in rat forestomach.
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Affiliation(s)
- H Y Kwon
- Konar Center for Digestive and Liver Diseases, University of Rochester School of Medicine and Dentistry, Rochester, New York 14624, USA
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Qiao W, Sun HH, Chey WY, Lee KY. Continuous wavelet analysis as an aid in the representation and interpretation of electrogastrographic signals. Ann Biomed Eng 1998; 26:1072-81. [PMID: 9846945 DOI: 10.1114/1.27] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
This paper presents an application of the continuous wavelet transform (CWT) in the analysis of electrogastrographic (EGG) signals. Due to the nonstationary nature of EGG signals, the CWT method, which uses multiresolution scaled windows, gives a better time-frequency resolution than the short-time Fourier transform, which uses a fixed window. Spike activity due to gastric contraction was investigated through experiments on dogs. During spike activity we observed an increase in magnitude of the slow wave and the appearance of a low frequency component with half the frequency of the slow wave. Studies of the EGG signals from the small intestine are also presented to investigate the hypothesis that its slow wave might be confounded with spike activity in the stomach due to the similarity of their frequency ranges.
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Affiliation(s)
- W Qiao
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, USA
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40
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Kalogeris TJ, Qin X, Chey WY, Tso P. PYY stimulates synthesis and secretion of intestinal apolipoprotein AIV without affecting mRNA expression. Am J Physiol 1998; 275:G668-74. [PMID: 9756495 DOI: 10.1152/ajpgi.1998.275.4.g668] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We tested whether exogenous peptide YY (PYY) can stimulate synthesis and lymphatic secretion of intestinal apolipoprotein AIV (apo AIV). Rats with mesenteric lymph fistulas and right atrial cannulas were given continuous intravenous infusions of control vehicle or PYY at 25, 50, 75, 100, or 200 pmol . kg-1 . h-1. PYY (75-200 pmol . kg-1 . h-1) stimulated lymphatic apo AIV output from 1.5- to 3.5-fold higher than basal output. In separate experiments, PYY (100 pmol . kg-1 . h-1) produced a 60% increase in jejunal mucosal apo AIV synthesis but had no effect on mucosal apo AIV mRNA levels at doses up to 200 pmol . kg-1 . h-1. Finally, exogenous PYY infusion (100 pmol . kg-1 . h-1) produced a plasma PYY increment of 30 pM compared with an increment of 18.7 pM in response to ileal infusion of lipid. These results support the hypothesis that PYY may be an endocrine mediator of the effects of distal gut lipid on production and release of intestinal apo AIV, likely via a posttranscriptional mechanism of action.
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Affiliation(s)
- T J Kalogeris
- Department of Surgery, Louisiana State University Medical Center, Shreveport, Louisiana 71130, USA
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41
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Abstract
Nerve fibers containing bombesin (BB)/gastrin-releasing polypeptide (GRP), pituitary adenylate cyclase-activating polypeptide (PACAP), vasoactive intestinal polypeptide (VIP), or galanin are known to innervate the mucosa of the upper small intestine. Both BB/GRP and PACAP have been shown to elicit secretin secretion in vivo. We studied whether the above-mentioned neuropeptides can act directly on secretin-producing cells, including the murine neuroendocrine cell line STC-1 and a secretin cell-enriched preparation isolated from rat upper small intestinal mucosa. Secretin release from both cell types was stimulated by various agents known to elicit secretin release and by the neuropeptides BB, GRP, and PACAP, suggesting a comparable response between the two cell preparations. The effects of neuropeptides were further studied in STC-1 cells. BB, GRP, and PACAP stimulated secretin release time and concentration dependently. VIP also stimulated secretin release concentration dependently. Stimulation by BB/GRP or PACAP was accompanied by elevation of inositol-1,4,5-trisphosphate (IP3) or cAMP, respectively. The stimulatory effect of PACAP on secretin release was synergistically enhanced by BB without any synergistic increase in IP3 or cAMP production, suggesting cross talk between different signal transduction pathways downstream of the production of these two second messengers. The L-type Ca2+ channel blocker diltiazem (10 microM) and the Ca2+ chelator EGTA (1 mM) significantly inhibited BB-stimulated secretin release by 64% and 59%, respectively, and inhibited PACAP-stimulated release by 75% and 55%, respectively. The protein kinase A-specific inhibitor Rp-cAMPS (100 microM) also inhibited both BB- and PACAP-stimulated secretin release by 30% and 62%, respectively. Galanin inhibited BB- and PACAP-stimulated secretin release and production of second messengers in a concentration-dependent and pertussis toxin-sensitive manner. These results suggested that the neuropeptides BB/GRP, PACAP, VIP, and galanin can modulate secretin release in secretin-producing cells and that STC-1 cells can serve as a useful model for studying the cellular mechanism of secretin secretion elicited by luminal secretagogues and neuropeptides.
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Affiliation(s)
- C H Chang
- The Konar Center for Digestive and Liver Diseases, Department of Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642, USA
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42
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Abstract
Secretin is an enterogastrone that inhibits gastric acid secretion and motility. Recently, it was reported that secretin inhibited gastric emptying via a capsaicin (Cap)-sensitive vagal afferent pathway. However, a possible role of the sensory afferent pathway in secretin-inhibited acid secretion has not been clarified. We investigated whether or not the acid secretion suppressed by secretin is modulated by a vagal and/or splanchnic afferent pathway in rats. Subdiaphragmatic perivagal (PV) or periceliac ganglionic (PCG) application of Cap (10 mg/ml) or vehicle was performed in both conscious and anesthetized rats 2 wk before experiments. Bilateral vagotomy was performed in some conscious rats 5 days before studies. Pentagastrin was administered intravenously at 0.6 microg . kg-1 . h-1. Secretin (20 pmol . kg-1 . h-1 iv) or 0.03 N HCl (4.32 ml/h id) was infused in conscious rats with gastric cannulas or anesthetized rats with ligation of the pylorus, respectively. A rabbit antisecretin serum was injected in some anesthetized rats before duodenal acidification. Secretin significantly inhibited pentagastrin-stimulated acid secretion by 63% (P < 0.01), which was abolished by both vagotomy and PV treatment of Cap in conscious rats. In anesthetized rats, duodenal infusion of 0.03 N HCl suppressed pentagastrin-induced acid secretion by 59.4% (P < 0.01), which was reversed not only by antisecretin serum but also by PV application of Cap. However, PCG treatment with Cap did not influence the inhibition by secretin or duodenal acidification in either awake or anesthetized rats. These results indicate that the inhibition by secretin of pentagastrin-stimulated acid secretion is mediated by a Cap-sensitive vagal afferent pathway but not via a splanchnic afferent pathway in rats.
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Affiliation(s)
- P Li
- Konar Center for Digestive and Liver Diseases, University of Rochester Medical Center, Rochester, New York 14626, USA
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Lee ST, Lee KY, Li P, Coy D, Chang TM, Chey WY. Pituitary adenylate cyclase-activating peptide stimulates rat pancreatic secretion via secretin and cholecystokinin releases. Gastroenterology 1998; 114:1054-60. [PMID: 9558296 DOI: 10.1016/s0016-5085(98)70326-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Pituitary adenylate cyclase-activating polypeptide (PACAP) stimulates protein and/or amylase secretion from isolated rat pancreatic acini. The effect of PACAP on pancreatic secretion in vivo and its mechanism of action were studied. METHODS Rats were prepared with pancreatic duct cannulation, pyloric ligation, and bile diversion into duodenum, and 2.5, 5, and 10 nmol/kg PACAP-27 was administered intravenously while pancreatic juice was collected for 30 minutes. In other groups of rats, the effect of 10 nmol/kg PACAP-27 was studied under the influence of either atropine; loxiglumide, an antisecretin serum; a combination of both loxiglumide and the antiserum; or a PACAP antagonist (PACAP 6-38). Plasma secretin and cholecystokinin concentrations were measured by radioimmunoassay. RESULTS (1) PACAP dose-dependently increased pancreatic secretion of fluid, bicarbonate, and protein; (2) the increase in pancreatic secretion paralleled that of plasma secretin and cholecystokinin; (3) a combination of loxiglumide and antisecretin serum eliminated the PACAP-stimulated pancreatic secretion, whereas loxiglumide or antisecretin serum alone partially but significantly blocked pancreatic secretion; (4) atropine failed to influence PACAP-induced pancreatic secretion; and (5) PACAP antagonist profoundly suppressed the PACAP action. CONCLUSIONS PACAP-27 dose-dependently stimulates pancreatic secretion of fluid, bicarbonate, and protein in rats. This effect is mediated by release of both secretin and cholecystokinin and is independent of cholinergic tone.
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Affiliation(s)
- S T Lee
- Konar Center for Digestive and Liver Diseases, University of Rochester Medical Center, Rochester, New York 14642, USA
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Jyotheeswaran S, Shah AN, Jin HO, Potter GD, Ona FV, Chey WY. Prevalence of Helicobacter pylori in peptic ulcer patients in greater Rochester, NY: is empirical triple therapy justified? Am J Gastroenterol 1998; 93:574-8. [PMID: 9576450 DOI: 10.1111/j.1572-0241.1998.167_b.x] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVES Among patients with peptic ulcer disease, the prevalence of Helicobacter pylori has been reported to range from 80% to 90%. Thus empirical cost-effective therapy has been suggested. We surveyed patients with peptic ulcer disease in Rochester, NY. METHODS From two teaching hospitals all patients who had duodenal ulcers (DU) and/or gastric ulcers (GU) on esophagogastroduodenoscopy (EGD) with antral biopsy for histology for H. pylori and for rapid urease (CLO) test were included in the study. We examined a total of 160 patients with DU and 145 patients with GU, age range 18-92 yr, obtaining clinical data, race, medication profile, and history of use of nonsteroidal antiinflammatory drugs (NSAIDs). An ulcer was defined if the lesion with loss of mucosal integrity was > or = 0.5 cm, with apparent depth. H. pylori was considered present if CLO test and/or histology were positive for H. pylori. To confirm the reliability of nonuse of NSAIDs, we randomly checked blood samples of 90 such patients from the ambulatory clinic for the presence of salicylates. To identify the sensitivity of the CLO test, we performed a serology test for H. pylori antibody in 100 subjects to compare the CLO test results. Also, 500 CLO test results were compared to the histology results for H. pylori. RESULTS Among 160 DU patients, 16 were NSAID users with negative H. pylori and excluded from the prevalence study. Of the remaining 144 patients with DU, H. pylori was present in 88 patients (61%). When these data were analyzed according to race, H. pylori was present in 54 (52%) of 104 whites compared to 34 of 40 (85%) nonwhites (blacks, Hispanics, Asians) (p < 0.01). Among 145 GU patients 18 were NSAID users with negative H. pylori and excluded from the prevalence analysis. Of the remaining 127 patients with GU, H. pylori was present in 87 patients (61%). Among them, H. pylori was present in 46 of 87 (53%) whites, whereas 31 of 40 nonwhites (78%) were H. pylori-positive (p < 0.01). Antral histology and CLO test for H. pylori were in agreement in 92% of cases. Serology and CLO test for H. pylori were in agreement in 87% of cases. None of the randomly screened patients, including 16 ulcer patients with negative H. pylori, showed presence of salicylate in blood. CONCLUSION In greater Rochester, NY, where the majority of our patients with EGD were whites, the prevalence of H. pylori among ulcer patients was lower compared to other regions, particularly among whites. This suggests that an additional causative factor or factors for peptic ulcers may be present. Hence, empirical antibiotic therapy of ulcer patients without confirming the presence of H. pylori may not be justified.
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Affiliation(s)
- S Jyotheeswaran
- The Konar Center for Digestive and Liver Diseases, University of Rochester Medical Center, New York 14642, USA
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Park HS, Lee YL, Kwon HY, Chey WY, Park HJ. Significant cholinergic role in secretin-stimulated exocrine secretion in isolated rat pancreas. Am J Physiol 1998; 274:G413-8. [PMID: 9486197 DOI: 10.1152/ajpgi.1998.274.2.g413] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Effects of intrapancreatic cholinergic activation by electrical field stimulation (EFS) on secretin-stimulated pancreatic exocrine secretion were investigated in the totally isolated perfused rat pancreas. EFS at 15 V, 2 ms, and 8 Hz for 45 min markedly increased spontaneous pancreatic secretion. This increase was completely inhibited by tetrodotoxin (1 microM) but not by hexamethonium (100 microM). Atropine (2 microM) significantly reduced the EFS-evoked volume flow and amylase output by 52% and 80%, respectively. EFS further increased the secretin (12 pM)-stimulated pancreatic secretion of fluid and amylase. The increases of the two parameters were significantly suppressed by atropine by 28% and 72%, respectively. Interestingly, EFS significantly increased concentrations of somatostatin-like immunoreactivity in portal venous effluents. When pertussis toxin (200 ng/ml) or rabbit antisomatostatin serum (0.1 ml/10 ml; titer of 1:50,000) was intra-arterially administered, EFS further increased the secretin-stimulated pancreatic secretion. In conclusion, the activation of intrapancreatic cholinergic neurons potentiated the secretin action on pancreatic exocrine secretion in the rat. This potentiating effect was significantly reduced by local somatostatin released during EFS that activated intrapancreatic cholinergic tone.
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Affiliation(s)
- H S Park
- Department of Physiology, College of Medicine, Hallym University, Chunchon, Korea
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Shimizu K, Kato Y, Shiratori K, Ding Y, Song Y, Furlanetto R, Chang TM, Watanabe S, Hayashi N, Kobayashi M, Chey WY. Evidence for the existence of CCK-producing cells in rat pancreatic islets. Endocrinology 1998; 139:389-96. [PMID: 9421438 DOI: 10.1210/endo.139.1.5691] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Although the existence of cholecystokinin-like immunoreactivity (CCK-LI) in rat pancreas had been reported previously, it was never clearly demonstrated whether CCK is produced in rat pancreatic islets. AIMS The purpose of this study was to elucidate the source of the CCK-LI, the molecular properties of CCK, and the expression of the CCK gene in islet cells. METHODS Immunohistochemical studies of rat pancreas were carried out with different rabbit antisera against CCK-8 and CCK-related peptide including N-terminal CCK-33 (1-22) and gastrin-17, and colocalization with known islet hormones including insulin, glucagon, somatostatin, and pancreatic polypeptide was investigated. The major molecular form of CCK in the islets was determined by HPLC. RT-PCR and in situ hybridization were performed to demonstrate the presence of the CCK transcript in the pancreas. RESULTS CCK-LI was found in the center of the islets, colocalized with insulin in B cells. The major molecular form of CCK in the islets was CCK-8. A 350-nucleotide fragment of PCR-amplified CCK cDNA was detected in the islet as well as the duodenum by RT-PCR. In situ hybridization showed that CCK messenger RNA was located in a large portion of the islets, and this was consistent with the immunohistochemical findings. CONCLUSION CCK messenger RNA and immunoreactivity are expressed in adult rat pancreatic islets, indicating that CCK-producing cells are present in adult rat islets.
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Affiliation(s)
- K Shimizu
- Department of Gastroenterology, Tokyo Women's Medical College, Japan
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47
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Abstract
BACKGROUND & AIMS A nongastrin acid-stimulating peptide (NGASP) has been found in ulcerogenic pancreatic tumor syndrome without hypergastrinemia. The mechanism of gastric acid hypersecretion by NGASP was investigated in rats. METHODS In vivo, gastric acid secretion and in vitro histamine release from enterochromaffin-like (ECL) cells in responses to tumor extract (TE) and synthetic human gastrin-17 I or pentagastrin (PG) were studied. Whether the 2 secretagogues potentiate each other was determined. RESULTS TE dose-dependently stimulated histamine release, which was not blocked by a cholecystokinin (CCK)-B receptor antagonist. When TE was incubated with trypsin, the activity was abolished but was not affected by antibody. However, when rats were pretreated with antigastrin serum or CCK-B receptor antagonist, the acid secretion by TE was virtually abolished. The dose response of acid secretion to TE in the rats receiving PG in a threshold dose was significantly greater than that achieved by TE alone. Similarly, the dose response to PG combined with a threshold dose of TE was significantly greater than that produced by PG alone. CONCLUSIONS NGASP stimulates histamine release from ECL cells, but the release is not mediated via CCK-B/gastrin receptor. NGASP and gastrin may potentiate each other to produce acid hypersecretion in ulcerogenic pancreatic tumor syndrome.
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Affiliation(s)
- Y Song
- Department of Medicine, William B. and Sheila Konar Center For Digestive and Liver Diseases, University of Rochester Medical Center, New York, USA
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Zwick A, Munir M, Ryan CK, Gian J, Burt RW, Leppert M, Spirio L, Chey WY. Gastric adenocarcinoma and dysplasia in fundic gland polyps of a patient with attenuated adenomatous polyposis coli. Gastroenterology 1997; 113:659-63. [PMID: 9247488 DOI: 10.1053/gast.1997.v113.pm9247488] [Citation(s) in RCA: 129] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Gastric adenocarcinoma has been previously recognized as a potential complication of familial adenomatous polyposis coli (APC) and attenuated forms of APC (AAPC). This tumor has only been reported to originate from adenomatous polyps of the gastric mucosa in these clinical conditions. There have been no previous case reports of gastric adenocarcinoma arising from the more commonly found fundic gland polyps associated with AAPC or APC. We report the first definitive case of gastric adenocarcinoma arising from a hyperplastic polyp of the fundis of a patient with AAPC.
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Affiliation(s)
- A Zwick
- William B. and Shella Konar Center for Digestive and Liver Diseases, University of Rochester Medical Center, New York, USA
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Song CW, Lee KY, Kim CD, Chang TM, Chey WY. Effect of cisapride and renzapride on gastrointestinal motility and plasma motilin concentration in dogs. J Pharmacol Exp Ther 1997; 281:1312-6. [PMID: 9190867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The effects of cisapride and renzapride (BRL 24924), on plasma concentration of motilin and gastroduodenal motility were studied in seven dogs with implanted force transducers in the antrum and duodenum. In the interdigestive state, the i.v. administration of cisapride (5 mg) or renzapride (5 mg) administered in phase I resulted in a prompt and marked increase in plasma motilin concentration and in gastroduodenal motility. Mean plasma motilin levels during the first 30 min after cisapride and after renzapride injection were 85.0 +/- 6.5 (+/- S.E.) and 96.1 +/- 6.3 pM., respectively. These values were significantly greater (P < .001) than those for the corresponding time period of the control cycle, 52.2 +/- 5.6 and 57.4 +/- 5.3 pM (mean phase III level, 120 +/- 8.1 pM), respectively. The increases in the motilin level after cisapride or renzapride coincided with significant increases in contractile activities of the antrum to 43.2 +/- 5.3% and 44.9 +/- 4.6% and of the duodenum to 28.4 +/- 3.1% and 34.2 +/- 2.2% of phase III activity (100%) from that in the corresponding control period, 0.7 +/- 0.4% and 0.2 +/- 0.1%, respectively. The changes in both plasma motilin and motility in response to the two drugs were abolished completely by the i.v. administration of atropine. The drugs also enhanced the meal-induced contractile activities of the antrum as well as the duodenum but failed to influence the postprandial plasma motilin concentration. We conclude that cisapride and renzapride have similar effects on plasma motilin and gastroduodenal motility: 1) the two drugs increase plasma motilin levels and stimulate gastroduodenal motility in the interdigestive state, and 2) in the digestive state, both drugs enhance motility without influencing the plasma motilin levels.
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Affiliation(s)
- C W Song
- Konar Center for Digestive and Liver Diseases, Department of Medicine, University of Rochester Medical Center, New York 14642, USA
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50
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Affiliation(s)
- D Joseph
- William B. and Sheila Konar Center for Digestive and Liver Diseases, Rochester, New York, USA
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