The Experts below are selected from a list of 1266 Experts worldwide ranked by ideXlab platform
Jens J. Holst - One of the best experts on this subject based on the ideXlab platform.
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the release of Gastric Inhibitory Peptide glucagon like Peptide i and insulin after oral glucose test in colectomized subjects
Scandinavian Journal of Gastroenterology, 1997Co-Authors: Palnaes C Hansen, Jan Jesper Andreasen, Jens J. HolstAbstract:Background: The physiologic role of the colon as an endocrine organ is not clear. We therefore studied the enteroinsular axis in patients with ulcerative colitis after colectomy. Methods: The subjects included 11 patients with a conventional ileostomy, 10 patients with an ileoanal reservoir, and 10 normal controls. The concentrations of glucose, insulin, Gastric Inhibitory Peptide (GIP), and glucagon-like Peptide-I (GLP-I) were measured in plasma during an oral glucose test. Results: The peak level of glucose and peak levels and area under the curve (AUC) of insulin and GIP were higher in patients (P < 0.05). Neither the peak level nor the AUC of GLP-I differed between patients and controls, but time to peak level was four times longer in patients with an ileoanal reservoir (P<0.05). Conclusion: Colectomy seems to affect the enteroinsular axis, leading to hyperinsulinemia and an impaired glucose tolerance. Moreover, patients with an ileoanal reservoir have a slower GLP-I response after intake of glucose.
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The Release of Gastric Inhibitory Peptide, Glucagon-Like Peptide-I, and Insulin after Oral Glucose Test in Colectomized Subjects
Scandinavian journal of gastroenterology, 1997Co-Authors: C. Palnaes Hansen, Jan Jesper Andreasen, Jens J. HolstAbstract:Background: The physiologic role of the colon as an endocrine organ is not clear. We therefore studied the enteroinsular axis in patients with ulcerative colitis after colectomy. Methods: The subjects included 11 patients with a conventional ileostomy, 10 patients with an ileoanal reservoir, and 10 normal controls. The concentrations of glucose, insulin, Gastric Inhibitory Peptide (GIP), and glucagon-like Peptide-I (GLP-I) were measured in plasma during an oral glucose test. Results: The peak level of glucose and peak levels and area under the curve (AUC) of insulin and GIP were higher in patients (P < 0.05). Neither the peak level nor the AUC of GLP-I differed between patients and controls, but time to peak level was four times longer in patients with an ileoanal reservoir (P
Meike Körner - One of the best experts on this subject based on the ideXlab platform.
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Specific biology of neuroendocrine tumors: Peptide receptors as molecular targets
Best Practice & Research Clinical Endocrinology & Metabolism, 2016Co-Authors: Meike KörnerAbstract:Neuroendocrine tumors (NET) are characterized by a high over-expression of many different Peptide hormone receptors. These receptors represent important molecular targets for imaging and therapy, using either radiolabeled or cold Peptide analogs. The clinically best established example is somatostatin receptor targeting. A relatively new application is glucagon-like Peptide 1 (GLP-1) receptor-targeted imaging of insulinomas, which is highly sensitive. A potential future candidate for Peptide receptor targeting is the Gastric Inhibitory Peptide (GIP) receptor. It was recently found to exhibit a very wide expression in NET and may be a particularly suitable target in somatostatin and GLP-1 receptor negative tumors. With increasing use of Peptide receptor targeting, reliable morphologic in vitro tools to assess Peptide receptors in tissues are mandatory, such as in vitro receptor autoradiography or thoroughly established immunohistochemical procedures.
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Does somatostatin or Gastric Inhibitory Peptide receptor expression correlate with tumor grade and stage in gut neuroendocrine tumors
Neuroendocrinology, 2015Co-Authors: Meike Körner, Beatrice Waser, Jean Claude ReubiAbstract:Background/Aims: Important characteristics of neuroendocrine neoplasms (NEN) for prognosis and therapeutic decisions are the MIB-1 proliferative index (tumor grade) and tumor stage. Moreover, these tumors express Peptide hormone receptors like somatostatin and Gastric Inhibitory Peptide (GIP) receptors which represent important established and potential future targets, respectively, for molecular imaging and radiotherapy. However, the interrelation between tumor proliferation, stage, and Peptide receptor amounts has never been assessed. Methods: In 114 gastrointestinal and bronchopulmonary NEN, the proliferative rate assessed with MIB-1 immunohistochemistry and tumor stage were compared with the somatostatin type 2 receptor (sst2) and GIP receptor expression measured quantitatively with in vitro receptor autoradiography. Results: NEN generally showed high sst2 and GIP receptor expression. GIP receptor but not sst2 expression correlated with the MIB-1 index. GIP receptor levels gradually increased in a subset of insulinomas and nonfunctioning pancreatic NEN, and decreased in ileal and bronchopulmonary NEN with increasing MIB-1 rate. MIB-1 levels were identified, above which GIP receptor levels were consistently high or low. These MIB-1 levels were clearly different from those defining tumor grade. In grade 3 NEN, GIP receptor levels were always low, while sst2 levels were variable and sometimes extremely high. Conversely, sst2 expression correlated more frequently with tumor stage than GIP receptor expression, with metastasized NEN showing higher sst2 levels than localized tumors. Conclusions: sst2, a clinically crucial molecular target, shows variable and unpredictable expression in NEN irrespective of tumor grade. Therefore, each NEN should be tested for sst2 if clinical applications with somatostatin analogs are considered. Conversely, the potential future role of GIP receptors as molecular targets in NEN may be dependent on the MIB-1 level.
T Masuhara - One of the best experts on this subject based on the ideXlab platform.
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Effects of vasoactive intestinal Peptide and its homologues on the acetylcholine-mediated secretion of fluid and protein from the rat submandibular gland.
General pharmacology, 1995Co-Authors: Y Iwabuchi, T MasuharaAbstract:1. Acetylcholine-mediated (ACh-mediated) secretion of fluid and protein from rat submandibular glands was enhanced by intravenous injection of vasoactive intestinal Peptide (VIP) and of secretin but not of Peptide histidine isoleucine (PHI) or Gastric Inhibitory Peptide (GIP). 2. When VIP and ACh were administered together, the enhancement of fluid secretion was inhibited by pretreatment with atropine or 4-DAMP and the enhancement of protein secretion was inhibited by pretreatment with atropine or phentolamine. 3. The enhancement of the ACh-induced secretion of fluid by secretin was strongly inhibited by pretreatment with atropine, and it was weakly inhibited by pretreatment with phentolamine or haloperidol. 4. These results suggest that the synergistic effects of VIP, PHI, secretin and GIP on the ACh-mediated secretion of fluid and protein from the rat submandibular gland do not reflect the extent of the structural homology of each Peptide to VIP.
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Effects of vasoactive intestinal Peptide and its homologues on the noradrenaline-mediated secretion of fluid and protein from the rat submandibular gland.
General pharmacology, 1994Co-Authors: Y Iwabuchi, T MasuharaAbstract:1. Noradrenaline-mediated secretion of fluid and protein from rat submandibular glands was enhanced by vasoactive intestinal Peptide (VIP) and secretin but not by Peptide histidine isoleucine (PHI) or Gastric Inhibitory Peptide (GIP). 2. The synergistic effect of the combination of VIP with noradrenaline (NA) was antagonized by pretreatment with prazosin or phentolamine but not by pretreatment with yohimbine or propranolol. 3. These results suggest that VIP and secretin but not PHI and GIP can significantly enhance the secretion of fluid and protein that is mediated by NA in rat submandibular gland and that the synergistic effect of VIP and NA involves both alpha 1-adrenergic receptors and receptors for VIP.
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Effects of vasoactive intestinal Peptide and its homologues on the substance P-mediated secretion of fluid and protein from the rat submandibular gland.
General pharmacology, 1994Co-Authors: Y Iwabuchi, T MasuharaAbstract:1. Acetylcholine-mediated (ACh-mediated) secretion of fluid and protein from rat submandibular glands was enhanced by intravenous injection of vasoactive intestinal Peptide (VIP) and of secretin but not of Peptide histidine isoleucine (PHI) or Gastric Inhibitory Peptide (GIP). 2. When VIP and ACh were administered together, the enhancement of fluid secretion was inhibited by pretreatment with atropine or 4-DAMP and the enhancement of protein secretion was inhibited by pretreatment with atropine or phentolamine. 3. The enhancement of the ACh-induced secretion of fluid by secretin was strongly inhibited by pretreatment with atropine, and it was weakly inhibited by pretreatment with phentolamine or haloperidol. 4. These results suggest that the synergistic effects of VIP, PHI, secretin and GIP on the ACh-mediated secretion of fluid and protein from the rat submandibular gland do not reflect the extent of the structural homology of each Peptide to VIP.
A. Weyns - One of the best experts on this subject based on the ideXlab platform.
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A stereological evaluation of secretin and Gastric Inhibitory Peptide-containing mucosal cells of the perinatal small intestine of the pig.
Journal of anatomy, 2004Co-Authors: C. Van Ginneken, A. WeynsAbstract:Stereological methods were used to quantify secretin and Gastric Inhibitory Peptide (GIP)-immunoreactivity (GIP-IR) in paraffin sections of the duodenum, jejunum and ileum of fetal and neonatal piglets. In addition, sections were processed for GLP-1-immunohistochemistry. The volume density of the tunica mucosa increased after birth, giving rise to a decreased volume density of the tela submucosa and tunica muscularis. Generally known region-specific morphological distinctions were reflected in differing volume densities of the various layers. The highest volume density of GIP-IR epithelial cells was observed in the jejunum of the neonate. In contrast, the volume density of secretin-IR epithelial cells was highest in the duodenum of both fetal and neonatal piglets. The volume occupied by GIP-IR and secretin-IR epithelial cells increased in the jejunum after birth. Additionally, ileal secretin-IR epithelial cells were more numerous in the neonatal piglet. In conclusion, the quantitative and qualitative presence of GIP-IR and secretin-IR epithelial cells agree with earlier reports of their presence and co-localization between GIP-IR and GLP-1-IR, in the pig small intestine. Furthermore, the differences suggest that age- and region-related functional demands are temporally and probably causally related with the morphological diversification of the intestine and its endocrine cells.
John N Forrest - One of the best experts on this subject based on the ideXlab platform.
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Gastric Inhibitory Peptide serotonin and glucagon are unexpected chloride secretagogues in the rectal gland of the skate leucoraja erinacea
American Journal of Physiology-regulatory Integrative and Comparative Physiology, 2014Co-Authors: Catherine A Kelley, Sarah E Decker, Patricio Silva, John N ForrestAbstract:Since the discovery of the rectal gland of the dogfish shark 50 years ago, experiments with this tissue have greatly aided our understanding of secondary active chloride secretion and the secretago...