Processed from a 160-amino acid proglucagon precursor, Glucagon is mainly secreted from the alpha-cells of the Islets of Langerhans, but is also produced in the L cells of the intestinal mucosa and in specialized neurons of the central nervous system (mainly in the hypothalamus and in the medulla oblongata).
Glucagon regulates glucose homeostasis
In response to low circulating blood glucose levels, glucagon acts on hepatic enzymes that regulate glucose production and glycogen synthesis to restore normal glucose levels.
It functions as a counter-regulatory hormone that opposes the actions of insulin and maintains the levels of blood glucose, particularly in patients with hypoglycemia.
Excessive amounts of circulating glucagon levels are implicated in the metabolic dysregulation of type 2 diabetes, since such conditions result in hyperglycaemia.
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