Parathyroid hormone

Contained in the parathyroid glands and promotes phosphorus-calcium metabolism. Regulates the exchange of calcium and phosphorus between blood and bone tissue: increases the level of calcium in the blood and reduces its reabsorption in the kidneys, increasing excretion in the urine; reduces bone resorption.

Produced by the parathyroid glands in response to an insufficient level of ionized calcium in the plasma or insufficient binding of calcium to blood proteins (hypercalciuria, hypophosphatemia, hypercysteinemia).