Exendin 4 is a 39 amino acid peptide found in venom from the Gila monster Helicoderma suspectum. It is a member of the glucagon secretin family of peptide hormones and neuropeptides. Exendin 4 is a potent agonist of the GLP1 receptor and hence a potent stimulator of insulin secretion. It stimulates insulin synthesis and secretion, protects against beta-cell apoptosis in response to different insults, and promotes beta-cell proliferation. It also promotes satiety, reduces food intake, reduces fat deposition, reduces body weight and inhibits gastric emptying. Interacts with GLP-1 receptor (GLP1R). Induces hypotension that is mediated by relaxation of cardiac smooth muscle.