Receptor for prostaglandin F2-alpha (PGF2-alpha). The activity of this receptor is mediated by G proteins which activate a phosphatidylinositol-calcium second messenger system. Initiates luteolysis in the corpus luteum. Highest expression in pregnant ovary. Also found in a low extent in the kidney. In the brain, expressed in astrocytes and oligodendrocytes, and meningeal fibroblasts, but not in migroglia cells. Belongs to the G-protein coupled receptor 1 family.