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How does glucagon increase the amount of glucose in the blood?
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human endocrine system
The principal glands of the female and male human endocrine systems.
Glucagon is a peptide hormone secreted by the alpha cells of the islets of Langerhans in the pancreas. It functions to increase blood glucose concentrations, particularly during fasting or exercise, by acting on the liver through two primary mechanisms:
- Glycogenolysis: Glucagon promotes the breakdown of glycogenāthe stored form of glucoseāinto glucose, which is then released into the bloodstream.1
- Gluconeogenesis: It stimulates the production of new glucose from non-carbohydrate sources, specifically amino acids and glycerol.1
By performing these actions, glucagon serves as a critical counter-regulatory hormone that opposes the effects of insulin, which works to lower blood glucose levels.12