QS Study

Glucagon secretion is regulated by glucose but the mechanisms involved remain hotly debated. In diabetes, the glucagon response to hypoglycemia becomes compromised and chronic hyperglucagonemia appears. The action of glucagon in the liver is multifaceted and involves organize regulation of transcription factors and signal transduction networks which converge on the regulation of amino acid, lipid, and carbohydrate metabolism.

Regulation of glucagon secretion

(1) Increase blood glucose inhibits glucagon secretion: Decrease blood glucose level increases glucagon secretion and increased blood glucose level conversely inhibit glucagon secretion.

(2) Increased blood amino acids stimulate glucagon secretion: High concentration of amino acids, as occurs in blood after a protein meal (Specifically the amino acids alanine and arginine). Stimulate the secretion of glucagon. Amino acids and their metabolites are central regulators of α-cell function.

The importance of amino acid stimulation of glucagon secretion is that the glucagon then promotes rapid conversion of the amino acids to glucose, thus making even more glucose available to the tissue.

(3) Exercise stimulates glucagon secretion: In an exhaustive exercise, the blood concentration of glucagon often increases fourfold to five fold.

Factors affecting glucagon secretion: