Definition

A recombinant form of a mature, N-terminal secretory peptide derived from a parathyroid hormone-related protein (PTHrP) preprohormone through posttranslational endoproteolytic processing with vasodilating, myorelaxant, and parathyroid hormone (PTH)-like calciotropic activities. Expressed throughout the cardiovascular system, parathyroid hormone-related protein (1-36) [PTHrP (1-36)] was first identified as the PTH-like hypercalcemic factor of humoral hypercalcemia of malignancy; however, its sequence differs significantly from that of PTH (1-34) although both proteins share the same N-terminal end which accounts for the calciotropic activity. Both PTHrP (1-36) and PTH (1-34) bind to the type 1 parathyroid hormone receptor (PTH1R), a specific seven-transmembrane-helix-containing G protein-coupled receptor mainly located in bone and kidney cells.