CCKBR (cholecystokinin B receptor) is a G protein-coupled receptor located on chromosome 11 that functions as both a gastrin and cholecystokinin receptor 1. The receptor activates multiple signaling pathways including Gαq/11-Ca2+, Gαs-cAMP, and β-arrestin-dependent mechanisms 2, with distinct conformations determining G protein selectivity 3. In the gastrointestinal system, CCKBR regulates gastric acid secretion, intestinal motility, and glucose absorption through PI3K/Akt signaling 4 and inhibits renal SGLT2-mediated glucose reabsorption via Erk/NF-κB pathways 5. In the central nervous system, CCKBR expression in the entorhinal cortex modulates memory and learning 3. Clinically, CCKBR variants are associated with peptic ulcer disease susceptibility through effects on Helicobacter pylori infection responses and gastric acid regulation 6. CCKBR+ cancer cells represent a stem cell-like subpopulation in gastric adenocarcinoma associated with poor prognosis and maintained through FOXO-mediated sialyltransferase activation 7. For Alzheimer's disease, selective Gq-biased CCKBR agonists reduce amyloid-β plaques and promote long-term potentiation via ADAM10 upregulation 3, while β-arrestin-biased agonists block potentiation and fear memory formation 2. The intestinal and renal gastrin/CCKBR axis shows therapeutic potential for type 2 diabetes management.