| [ Summary ] |
PTH-1 receptors and PTH-2 receptors that belong to the type-II G-protein coupling receptor superfamily were identified as human parathyroid hormone receptors. Those receptors are intensely localized in the kidneys and bones, however, they are also distributed in the brain, vascular walls, muscle, skin, liver, blood and other tissues, Therefore, all these tissues are potential targets for PTH. The related peptide (PTHrP) is another ligand for PTH-1 receptors, It may be considered to be a tuberoinfundibular peptide of 39 residues (TIP39) for PTH-2 receptors. Thus, we must consider the interactions with those other ligands and the effect of calcium / phosphate metabolic changes to investigate the extrarenal and extraskeletal action of PTH. |