Description |
Pancreatic Polypeptide, rat is an agonist of NPY receptor, with high affinity at NPYR4.
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Related Catalog |
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Target |
NPYR4[1]
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In Vitro |
Pancreatic Polypeptide, rat is an agonist of NPY receptor, with high affinity at NPYR4. Pancreatic Polypeptide (1 μM) does not alter proliferation in BRIN BD11 or 1.1B4 beta-cells, but reverses the decreased cell viability in BRIN BD11 cells induced by streptozotocin. Pancreatic Polypeptide (0.1 nM-1 μM) shows no effect on insulin secretion from isolated mouse islets, and does not affect the membrane potential and (Ca2+)i levels in BRIN BD11 cells at 1 μM[1].
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In Vivo |
Pancreatic Polypeptide (25 nmol/kg bw, i.p.) reduces glucose-stimulated insulin concentrations but shows no effect on acute feeding behaviour in overnight fasted mice[1].
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Cell Assay |
To assess the effects of NPY and Pancreatic Polypeptide on rodent BRIN-BD11 and human 1.1B4 beta-cell proliferation, cells are seeded at a density of 150,000 cells per well and cultured overnight in the presence of NPY or Pancreatic Polypeptide (1 μM), and compared to positive control GLP-1 (1 μM). Cells are washed with PBS and fixed using 4% paraformaldehyde. After antigen retrieval with citrate buffer at 95°C for 20 min, tissue is blocked using 2% BSA for 45 min. The slides are then incubated with rabbit anti-Ki-67 primary antibody, and subsequently with Alexa Fluor® 594 secondary antibody. Slides are viewed using fluorescent microscope and photographed by DP70 camera adapter system. Proliferation frequency is determined in a blinded fashion and expressed as % of total cells analysed. Approximately 150 cells per replicate are analysed. For analysis of ability of NPY and Pancreatic Polypeptide to protect against streptozotocin-induced DNA damage, BRIN-BD11 and 1.1B4 cells are seeded. Cells are then exposed to streptozotocin (5 mM) in the presence or absence of NPY or Pancreatic Polypeptide (1 μM) for 2 h, with GLP-1 (1 μM) as positive control. Cells are then harvested and a comet assay is performed. Resulting gels are stained using DAPI (4′,6-diamidino-2-phenylindole) (100 μg/mL) and slides are viewed under appropriate filter. Comet score software is used for the analysis of % tail DNA (100 cells per gel) and olive tail moment[1].
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Animal Admin |
Mice[1] Plasma glucose and insulin responses are evaluated after intraperitoneal (i.p.) injection of glucose alone (18 mmol/kg body weight) or in combination with test peptides (Pancreatic Polypeptide, etc.; 25 nmol/kg body weight) in overnight (18 h) fasted C57BL/6 mice. In a second series of experiments, 18 h fasted mice are used to assess the effects of respective test peptides on food intake. Mice receive an i.p. injection of saline alone (0.9% (w/v) NaCl) or in combination with test peptides (25 nmol/kg body weight) and food intake measured at 30 min intervals for 180 min. A dose of 25 nmol/kg is chosen with other NPYR modulators on glucose homeostasis, insulin secretion and feeding at this dose[1].
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References |
[1]. Khan D, et al. Influence of neuropeptide Y and pancreatic polypeptide on islet function and beta-cell survival. Biochim Biophys Acta. 2017 Apr;1861(4):749-758.
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