hormone
Glucagon
Glucagon is a pancreatic hormone that helps maintain blood glucose during fasting and between meals.
Educational draft · Human scientific and editorial review pending. About review status
Alpha cells release glucagon, which acts especially on the liver to promote glucose production and release when blood glucose is low.
How it works
A counter-regulatory signal
Glucagon binds receptors on liver cells and promotes glycogen breakdown and gluconeogenesis, helping make glucose available between meals. Its effect depends on nutritional and hormonal context; it is not simply an “opposite” switch that explains every blood-glucose change.
Related topics
Glucagon helps maintain availability of Glucose
Glucagon acts mainly on the liver to support glucose production and release between meals.
Evidence: Established · Source checked 2026-09-05 · Sources: NIH National Library of Medicine: Physiology, Endocrine Hormones
Worth knowing
It acts mainly through the liver. The liver is a major target for glucagon’s glucose-regulating actions; muscle does not release its glycogen into blood in the same way.
A closer look
Several signals regulate secretion
Glucagon secretion is influenced by blood glucose, amino acids and other pancreatic signals; hepatic glycogen breakdown and gluconeogenesis then affect glucose availability.
References
Source-checked local draft.
Human editorial review pending.