PTH1R, also known as PTHR1, is a protein that belongs to the G-protein coupled receptor 2 family. PTH1R is a receptor for parathyroid hormone and for parathyroid hormone-related peptide. The activity of this receptor is mediated by G proteins which activate adenylyl cyclase, and phosphatidylinositol-calcium second messenger system. Diseases associated with PTH1R include Jansen type metaphyseal chondrodysplasia and Blomstrand type Chondrodysplasia. Among its related pathways are endochondral ossification with skeletal dysplasias and GPCR downstream signaling.