Calcitonin R: ProductsThe Calcitonin Receptor (CALCR) is a glycosylated 70 kDa seven-transmembrane G protein-coupled receptor that mediates the hypocalcemic effects of the peptide hormone, calcitonin. CALCR activation inhibits osteoclast-mediated bone resorption and enhances renal calcium excretion. CALCR polymorphisms and mutations have been associated with several bone disorders. Alternate splicing of the Calcitonin Receptor results in the deletion of 16 aa in the first cytoplasmic loop or 23 aa in the first extracellular region. Human CALCR shares 70% - 72% aa sequence identity with mouse and rat CACLR.