Calcitonin receptor (CALCR) (CALCR)

The Calcitonin receptor (CALCR) is a high-affinity G protein-coupled receptor (GPCR) belonging to the Class B (secretin-like) family, primarily expressed on the surface of osteoclasts and in the kidneys (UniProt P30988; IUPHAR/BPS Guide to Pharmacology). Its primary biological role is the maintenance of calcium homeostasis by responding to the hormone calcitonin, which triggers signaling pathways that inhibit bone resorption and promote renal calcium excretion (StatPearls, Calcitonin). Upon activation, the receptor stimulates adenylate cyclase and phospholipase C, leading to a rapid reduction in the activity and motility of osteoclasts (UniProt P30988). In clinical practice, CALCR is a significant therapeutic target for metabolic bone diseases such as osteoporosis and Paget's disease, where calcitonin mimetics are used to preserve bone density (PubMed, PMID: 25103998). Beyond bone health, the receptor is also involved in central nervous system functions, including appetite regulation and pain modulation (IUPHAR/BPS Guide to Pharmacology). However, long-term therapeutic use of calcitonin agonists is often limited by tachyphylaxis due to receptor internalization and regulatory concerns regarding a potential slight increase in cancer risk (FDA Drug Safety Communication, 2013).

Other names

CTRCTR1CT-RCT receptor

Agonist activation of the receptor leads to increased intracellular cAMP and calcium levels, which inhibits the resorptive activity of osteoclasts and increases renal excretion of calcium (StatPearls; UniProt P30988).