Glycagon
Structure
Glucagon is a kind of peptide hormone with 29 amino acids in a linear structure. Glucagon is produced originally as a formation of proglucagon in the pancreas, which is then converted to glucagon as a functional state in alpha cells of the islets [1].
Function
The primary role of glucagon played in the body is increasing the blood glucose concentrations, which is the opposite function of insulin, secreted from beta cells of the islets. To be specific, glucagon raises the blood sugar levels through the breakdown of the glycogen in the liver when the concentration of the blood glucose is low [1]. This process is called glycogenolysis, which is decomposition of glycogen into glucose [2]. Another function of glucagon is activating gluconeogenesis, which convert non-hexose, for instance, amino acids, to glucose also for increasing the blood sugar levels [3]
Disease
Glucagonomas is a result of excessive seglucagon excretion, which causes some harm effects,for example, skin lesions [4].
References:
- ↑ 1.0 1.1 R.Bowen (1999), Glucagon, http://www.vivo.colostate.edu/hbooks/pathphys/endocrine/pancreas/glucagon.html (last accessed 09.01.11)
- ↑ Berg J., Tymoczko J. and Stryer L. (2007) Biochemistry, 6th edition, New York: WH Freeman(p601-603).
- ↑ Berg J., Tymoczko J. and Stryer L. (2007) Biochemistry, 6th edition, New York: WH Freeman(p770-771).
- ↑ R.Bowen (1999), Glucagon, http://www.vivo.colostate.edu/hbooks/pathphys/endocrine/pancreas/glucagon.html (last accessed 09.01.11)