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- Halim, Abdul, 1983-, et al.
(författare)
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Glucagon-like peptide-1 inhibits prandial gastrointestinal motility through myenteric neuronal mechanisms in humans
- 2018
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 103:2, s. 575-585
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Tidskriftsartikel (refereegranskat)abstract
- Context: Glucagon-like peptide-1 (GLP-1) secretion from L-cells and postprandial inhibition of gastrointestinal motility.Objective: Investigate whether physiological plasma concentrations of GLP-1 can inhibit human postprandial gastrointestinal motility; determine target mechanism of GLP-1 and analogue ROSE-010 action.Design: Single-blind parallel study.Setting: University research laboratory.Participants: Healthy volunteers investigated with antroduodenojejunal manometry. Human gastric, intestinal and colonic muscle strips.Interventions: Motility indices (MI) obtained before and during infusion of saline or GLP-1 were compared. Plasma GLP-1 and glucagon-like peptide-2 (GLP-2) measured by radioimmunoassay. Gastrointestinal muscle strips, pre-contracted with bethanechol/electric field stimulation (EFS), investigated for GLP-1- or ROSE-010-induced relaxation. GLP-1, GLP-2 and their receptors localized by immunohistochemistry. Action mechanisms studied employing exendin(9-39)amide, Lω-nitro-monomethylarginine (L-NMMA), 2´,5´-dideoxyadenosine (DDA), tetrodotoxin (TTX).Main outcome measures: Hypothesize postprandial gastric relaxation induced by GLP-1, the mechanism of which intrinsic neuronally-mediated.Results: Food intake increased MI to 6.4±0.3 (antrum), 5.7±0.4 (duodenum) and 5.9±0.2 (jejunum). GLP-1 administered intravenously raised plasma GLP-1, but not GLP-2. GLP-1 0.7 pmol/kg·min significantly suppressed MI to 4.6±0.2, 4.7±0.4 and 5.0±0.2, respectively, while 1.2 pmol/kg·min suppressed corresponding MI to 5.4±0.2, 4.4±0.3 and 5.4±0.3 (p<0.0001-0.005). GLP-1 and ROSE-010 prevented bethanechol- or EFS-induced muscle contractions (p <0.005-0.05). Inhibitory responses to GLP-1 and ROSE-10 were blocked by exendin(9-39)amide, L-NMMA, DDA or TTX (all p <0.005-0.05). GLP-1 and GLP-2 were localized to epithelial cells; GLP-1 also in myenteric neurons. GLP-1R and GLP-2R were localized at myenteric neurons but not muscle, GLP-1R also in epithelial cells.Conclusions: GLP-1 inhibits postprandial motility through GLP-1R at myenteric neurons, involving nitrergic and cAMP-dependent mechanisms.
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| 2. |
- Halim, Md. Abdul, 1983-, et al.
(författare)
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GLP-1 Inhibits Prandial Antro-Duodeno-Jejunal Motility in Humans: Native GLP-1 Compared With Analogue ROSE-010 In Vitro
- 2016
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Ingår i: Gastroenterology. - 0016-5085 .- 1528-0012. ; 150:4, suppl. 1, s. S97-S98
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Tidskriftsartikel (refereegranskat)abstract
- Background: Glucagon-like peptide-1 (GLP-1) is secreted from L-cells after nutrient ingestion, inhibiting motility. Aims: To clarify whether infused GLP-1 inhibits in vivo prandial motility response and determine the likeliest target cell type and mechanism of action of GLP-1 and its analogue ROSE-010 using in vitro human gut muscle strips. Methods: Sixteen healthy volunteers underwent antroduodenojejunal manometry. Recordings of 1 hour infusion of saline or GLP-1 (0.7 or 1.2 pmol/kg/min) were compared. Plasma GLP-1 and GLP-2 were measured by RIA. Gastrointestinal muscle strips from surgical re-sections, pre-contracted with bethanechol or electric field stimulation (EFS), were investigated for GLP-1 or ROSE-010 induced relaxation. GLP-1, GLP-2 and receptors for GLP-1 and GLP-2 (GLP-1R, GLP-2R) were visualized by immunohistochemistry. Mechanisms were studied employing exendin(9-39) amide, Lw-nitro-monomethyl arginine (L-NMMA), 2´5´-dideoxyadenosine (DDA) and tetrodotoxin (TTX). Results: Food-intake increased motility index from 4.0±0.5 to 6.4±0.3 (antrum), 4.2±0.4 to 5.7±0.4 (duodenum) and 4.6±0.3 to 5.9±0.2 (jejunum) ln(Σ(mmHg·s·min-1)). GLP-1 at 0.7 pmol/kg/minwas sufficient to suppress these indexes from 6.2±0.4 to 3.8±0.7, 5.6±0.6 to 3.9±0.6 and 5.8±0.1 to 4.6±0.4 ln(Σ(mmHg·s·min-1)). Both GLP-1 doses raised plasma GLP-1, but not GLP-2. GLP-1 (EC50 40 nM) and ROSE-010 (EC50 50 nM) relaxed bethanechol-induced contractions in muscle strips. Inhibitory responses were blocked by exendin(9-39) amide, L-NMMA, DDA or TTX pre-treatment. GLP-1R and GLP-2R were expressed in myenteric neurons, but not muscle. Conclusions: GLP-1 and ROSE-010 inhibit motility through GLP-1R at myenteric neurons, which also possess GLP-2 receptors. GLP-1 increases more than GLP-2 with meals and does not increase plasma GLP-2. GLP-1 and ROSE-010 relaxations are cAMP and NO dependent.
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