Glucagon

Glucagon is a a 29 amino acid polypeptide acting as an important hormone in carbohydrate metabolism. The polypeptide has molecular weight of 3485 daltons and was discovered in 1923 by Kimball and Murlin. They studied panreatic extracts and found a additional substance with hyperglycemic properties. Glucagon was sequenced in late 1950s. Fuller understanding of its role in physiology and disease was established in 1970s when a specific radioimmunoassay[?] was developed.

His-Ser-Gln-Gly-Thr-Phe-Thr-Ser-Asp-Tyr-Ser-Lys-Tyr-Leu-Asp-Ser-Arg-Arg-Ala-Gln-Asp-Phe-Val-Gln-Trp-Leu-Met-Asn-Th

Table of contents 1 Physiology 2 Pathology 3 Pharmacological application of glucagon 4 See also

Physiology The hormone is synthesized and secreted from A cells of pancreatic islets (islets of Langerhans).
Glucagon raises the level of glucose (sugar) in the blood by causing the liver to release its intracellular stores of glucose. Normally, the alpha cells[?] of the pancreas (in areas called the Islets of Langerhans) make glucagon in response to hypoglycaemia in the body.

Pathology

• glucagonoma[?]

Pharmacological application of glucagon

An injectable form of glucagon is essential first aid in cases of severe hypoglycemia. The glucagon is injected and quickly raises blood glucose levels. It works only if there is glucose stored in liver cells, and it won't work again until those stores are replenished.

Glucagon has also inotropic[?] properties. Although it is impracticable in heart failure, it has some value in treatmeant of myocardium depression of betablocker[?] overdose.

See also

• insulin
• diabetes mellitus