Neuroendocrine peptide which is produced by a subset of neurons in the hypothalamus. Activates the G-protein coupled receptors pth1ra, pth1rb and pth2r with similar affinity. Receptor binding stimulates intracellular cAMP production. Plays a role in bone mineralization by regulating expression of factors involved in phosphate homeostasis. Important for embryonic bone development. Specifically expressed in a bilateral cluster of neurons in the dorsal region of the periventricular hypothalamus. Their axons project through the midbrain and hindbrain and down the spinal cord. Detected at 0-3 hours post-fertilization (hpf), probably due to inheritance of maternal transcripts. Expression then declines, and increases again from 12 hpf onwards. Detected in the developing hypothalamus from 24 hpf. At 3 days post-fertilization (dpf), found in two subsets of neurons in the lateral hypothalamus. Up-regulated by runx2a. Belongs to the parathyroid hormone family.