glucagon

glu·ca·gon   (glōō'kə-gŏn')    n.  A hormone produced by the pancreas that stimulates an increase in blood sugar levels, thus opposing the action of insulin. [Probably gluc(o)- + Greek agōn, present participle of agein, to lead, drive; see ag- in Indo-European roots.]

Main Entry: glu·ca·gon
Pronunciation: 'glü-k&-"gän
Function: noun
: a protein hormone that is produced especially by thepancreatic islets of Langerhans and that promotes an increase in the sugar content of the blood by increasing the rate of breakdown of glycogen in the liver called also hyperglycemic factor,hyperglycemic-glycogenolytic factor

glucagon glu·ca·gon (gl&oomacr;'kə-gŏn')
n.
A polypeptide hormone secreted by alpha cells that initiates a rise in blood sugar levels by stimulating the breakdown of glycogen by the liver.

glucagon   (gl'kə-gŏn')  Pronunciation Key  A polypeptide hormone produced by the pancreas that stimulates an increase in blood glucose levels, thus opposing the action of insulin.

glucagon

a pancreatic hormone produced by cells in the islets of Langerhans. Glucagon, a protein of low molecular weight, strongly opposes the action of insulin; it raises the concentration of sugar (glucose) in the blood by promoting the breakdown of glycogen (the form in which glucose is stored in the liver). It also reduces the rate of glycogen synthesis, promotes the breakdown of protein, and promotes the metabolism of fat. Gastrointestinal glucagon, another form, is secreted into the blood when glucose is ingested; its only action appears to be to stimulate the secretion of insulin.

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