Calcitonin Receptor (CT)

The calcitonin receptor (CT or CTR) is a G protein-coupled receptor (GPCR) that binds the peptide hormone calcitonin. It plays a central role in maintaining calcium homeostasis, particularly influencing bone formation and metabolism. The receptor is primarily expressed on osteoclasts, kidney cells, and certain brain regions. It may also have effects in reproductive organs such as the ovaries and testes. Interaction with RAMPs alters the pharmacology of the CT receptor, enabling binding to additional ligands such as amylin beyond just calcitonin itself. Calcitonins are clinically approved drugs for treating bone diseases like osteoporosis.

Other names

CTRCALCR

Calcitonin binds to the calcitonin receptor (CT or CTR), a G protein-coupled receptor, leading to activation of adenylate cyclase (cAMP pathway) or phospholipase C (PLC), respectively. This results in an increase in intracellular cAMP levels or mobilization of intracellular Ca²⁺ stores and promoting external calcium influx, ultimately inhibiting osteoclast-mediated bone resorption and regulating calcium homeostasis.