Medication Description: Calcitonin (Calcitonin)
A hypocalcemic hormone produced by parafollicular light thyroid cells and similar cells of the thymus and parathyroid glands of mammals, animals and humans.
By chemical nature, calcitonin is a polypeptide consisting of 32 amino acid residues; molecular weight 3600 - 4000.
Currently, 8 types of calcitonin are known, of which calcitonin of salmon, pig and man are of medical importance. Developed synthetic methods for producing calcitonin.
The activity of the drug is expressed in units of action (ED) or international units (IU) and is determined by biological or radio-immunological method. In determining the biological method for 1 IU taken the amount of the hormone, causing in rats (under certain conditions of experience) a decrease in blood calcium by 10%. 1 IU corresponds to 0.2 µg of pure peptide (synthetic salmon calcitonin).
Abroad, natural and synthetic calcitonin preparations are available under the names: Calcimar, Calcitar, Calcitonin, Caldcalcin, Calirsan, Calsynar, Cibacalcin, Elcatonin, Miacalcic, Miacalcin, Salcatonin, Thyrocalcitonin, etc.
In our country, an injection dosage form of calcitonin from the thyroid gland of pigs called <Calcitrin> has been developed.
Calcitonin is constantly present in the blood. Its concentration is increased by eating foods rich in calcium salts.
The physiological role of calcitonin is determined by participation in the regulation of calcium and phosphate metabolism in the body; its action is carried out with the participation of parathyroid hormone and activating the form of vitamin D (see Ergocalciferol).
Calcitonin significantly reduces the release of calcium from the bones in such conditions that are associated with a sharply increased rate of resorption and bone formation, for example, with Paget's disease, malignant osteolysis and some forms of osteoporosis, characterized by a high level of mineral metabolism. The drug inhibits the activity of osteoclasts and stimulates the formation and activity of osteoblasts; inhibits osteolysis, reducing elevated calcium levels in serum. In addition, it increases the excretion of calcium, phosphorus and sodium in the urine by reducing their reabsorption in the renal tubules. However, serum calcium concentration does not fall below normal values.
Calcitonin also reduces gastric secretion and exocrine secretion of the pancreas, without affecting the mobility of the gastrointestinal tract. Clinical studies show that the drug has an analgesic effect.