Description
Parathyroid hormone is the most important endocrine regulator of calcium and phosphorus concentration inextracellular fluid. This hormone is secreted from cells of the parathyroid glands and finds its major target cellsin bone and kidney. Another hormone, parathyroid hormone-related protein, binds to the same receptor asparathyroid hormone and has major effects on development. Like most other protein hormones, parathyroidhormone is synthesized as a preprohormone. After intracellular processing, the mature hormone is packagedwithin the Golgi into secretory vesicles, the secreted into blood by exocytosis. Parathyroid hormone is secretedas a linear protein of 84 amino acids.