The hormone participates in calcium (Ca2+) and phosphorus metabolism. In many ways,<unk>  counteracts parathyroid hormone (PTH) and vitamin D. More specifically,<unk>  lowers blood Ca2+ levels in two ways: :* Major effect: Inhibits osteoclast activity in bones, which break down the bone :* Minor effect: Inhibits renal tubular cell reabsorption of Ca2+ and phosphate, allowing them to be excreted in the urine High concentrations of<unk>  may be able to increase urinary excretion of calcium and phosphate via the renal tubules. leading to marked hypocalcemia. However, this is a minor effect with no physiological significance in humans. It is also a short-lived effect because the kidneys become resistant to<unk> , as demonstrated by the kidney's unaffected excretion of calcium in patients with thyroid tumors that secrete excessive<unk> . In its skeleton-preserving actions,<unk>  protects against calcium loss from the skeleton during periods of calcium mobilization, such as pregnancy and, especially, lactation. The protective mechanisms include the direct inhibition of bone resorption and the indirect effect through the inhibition of the release of prolactin from the pituitary gland. The reason provided is that prolactin induces the release of PTH related peptide which enhances bone resorption, but is still under investigation., Other effects are in preventing postprandial hypercalcemia resulting from absorption of Ca2+. Also,<unk>  inhibits food intake in rats and monkeys, and may have CNS action involving the regulation of feeding and appetite.<unk>  lowers blood calcium and phosphorus mainly through its inhibition of osteoclasts. Osteoblasts do not have<unk>  receptors and are therefore not directly affected by<unk>  levels. However, since bone resorption and bone formation are coupled processes, eventually<unk> 's inhibition of osteoclastic activity leads to increased osteoblastic activity (as an indirect effect).
Calcitonin
Parathyroid hormone-related protein
Parathyroid hormone
Orexin
Thyroglobulin
Leptin
Calcitriol
Adiponectin