Enables cholecystokinin receptor activity. Involved in several processes, including positive regulation of somatostatin secretion; reduction of food intake in response to dietary excess; and regulation of metal ion transport. Located in several cellular components, including endosome; lysosome; and terminal bouton. Used to study obesity and type 2 diabetes mellitus. Biomarker of pancreatic cancer. Human ortholog(s) of this gene implicated in obesity. Orthologous to human CCKAR (cholecystokinin A receptor). [provided by Alliance of Genome Resources, Apr 2022]