By Taylor Kudirka

 Calcitonin is a hormone known to participate in calcium and phosphorus metabolism.  In mammals calcitonin is the C cells in the thyroid gland.

 Calcitonin was first purified in 1962 by Chopp and Cheney.  At first they believed it was a secretion of the parathyroid glands and was later identified as the secretion of the C-cells of the thyroid gland.

 This hormone participates in calcium and phosphorous metabolism.  Calcitonin counteracts the parathyroid gland.

 1. Inhibits calcium absorption by the intestines.  2. Inhibits osteoclast activity in bones.  3. Inhibits renal tubular cell reabsorption of calcium allowing it to be secreted into the urine.

 Calcitonin is a polypeptide hormone of 32 amino acids.  It weights about daltons.  Its structure comprises a single alpha helix.

 Calcitonin can be used as a tumor maker for medullary thyroid cancer.  It can also be used on biopsy samples to establish whether they are metastasis of the original cancer.

Calcitonin is secreted from the thyroid glands

 Calcitonin is very important for women because it helps protect against calcium loss during pregnancy and lactation.

The End