Enzyme Immunoassay (E), Immunoprecipitation (IP), Radioimmunoassay (R)
Exendin-3 stimulates vasoactive intestinal peptide (VIP) receptors in high concentrations (>100 nM), resulting in both an increase in cAMP and amylase secretion from pancreatic acini, although at low concentrations (between 0.3 and 3 nM) it increases cAMP without stimulating amylase release. It stimulates the GLP-1 receptor (GLP1R). Induces hypotension that is mediated by relaxation of cardiac smooth muscle.Exendin-3 is expressed by the venom gland. [Lys40(68Ga-DOTA)]exendin-3 is a promising tracer to visualize insulinomas (neuroendocrine tumors derived from pancreatic beta-cells in which GLP1R is expressed at >90%) with PET imaging.
"Exendin-3, a novel peptide from Heloderma horridum venom, interacts with vasoactive intestinal peptide receptors and a newly described receptor on dispersed acini from guinea pig pancreas. Description of exendin-3(9-39) amide, a specific exendin receptor antagonist." Raufman J.P., Singh L., Eng J. J. Biol. Chem. 266:2897-2902(1991)
"Novel venom proteins produced by differential domain-expression strategies in beaded lizards and gila monsters (genus Heloderma)." Fry B.G., Roelants K., Winter K., Hodgson W.C., Griesman L., Kwok H.F., Scanlon D., Karas J., Shaw C., Wong L., Norman J.A. Mol. Biol. Evol. 27:395-407(2010)
"68Ga-labelled exendin-3, a new agent for the detection of insulinomas with PET." Brom M., Oyen W.J., Joosten L., Gotthardt M., Boerman O.C. Eur. J. Nucl. Med. Mol. Imaging 37:1345-1355(2010)