- Peptide (C)EGQTTGELYQRWER,corresponding to amino acid residues 25-38 of rat GIPR (Accession P43219). Extracellular, N-terminus.
- Western blot analysis of rat brain membranes (lanes 1 and 5), mouse brain membranes (lanes 2 and 6), rat pancreas membranes (lanes 3 and 7) and mouse heart membranes (lanes 4 and 8):1-4. Anti-GIPR (extracellular) Antibody (#AGR-025), (1:200).
5-8. Anti-GIPR (extracellular) Antibody, preincubated with GIPR (extracellular) Blocking Peptide (#BLP-GR025).
- Expression of Gastric inhibitory polypeptide receptor in rat hippocampusImmunohistochemical staining of perfusion-fixed frozen rat brain sections using Anti-GIPR (extracellular) Antibody (#AGR-025), (1:400), followed by anti-rabbit-Alexa-488 antibody. GIPR is expressed (green) in the pyramidal layer (P) of the CA1 rat hippocampal region. Nuclei are labeled with DAPI (blue).
- Cell surface detection of GIPR receptor α by indirect flow cytometry in live intact mouse BV-2 microglia cells:___ Cells.
___ Cells + goat-anti-rabbit-FITC.
___ Cells + Anti-GIPR (extracellular) Antibody (#AGR-025), (2.5μg) + goat-anti-rabbit-FITC.
Gastric inhibitory polypeptide (GIP) is a 42-amino acid hormone released from the gastrointestinal tract and was first found to inhibit the secretion of hydrochloric acid from stomach parietal cells. GIP also stimulates postprandial insulin secretion from pancreatic β-cells following a pathway activated by the binding of GIP to its specific receptor thus making GIP, along with GLP-1, a major potentiator of glucose induced insulin secretion1.
The human GIP receptor is a 466 amino-acid G-coupled protein receptor that is 81.5% and 81.2% identical to the hamster and rat receptors comprising seven potential transmembrane domains. This property is shared with glucagon and secretin receptor families.
GIP has an affinity of Kd~0.2 nM to its receptor. GIPR activates several intracellular pathways including MAP kinase, phospholipase A2 but primarily activates adenylyl cyclase causing an increase in cAMP. GIP has been also found to be expressed outside the gut in organs such as the heart, brain and adipose tissue.
In patients with Type 2 Diabetes-Mellitus, GIP levels are normal or at most minimally reduced therefore suggesting that there is a resistance of β-cells to GIP caused by a change in receptor expression signaling or mutation. In addition, mice whose GIPR gene expression is disrupted, following three months of high fat feeding, show reduced weight gain and adipose tissue compared to regular mice suggesting the elimination of this receptor may protect against the onset of severe obesity2.
Species reactivity key:
Anti-GIPR (extracellular) Antibody (#AGR-025) is a highly specific antibody directed against an epitope of the rat Gastric inhibitory polypeptide receptor. The antibody can be used in western blot and immunohistochemistry applications. The antibody recognizes an extracellular epitope and can potentially detect the receptor in living cells. It has been designed to recognize GIPR from rat, human, and mouse samples.