Bio Chemistry

BIOCHEMISTRY 3(2+1)

Lesson 19 : Glycogenolysis

Regulation of glycogen metabolism

Mobilization and synthesis of glycogen is under hormonal control. Three hormones involved:

1. insulin

• Protein made by a cells of pancreas.
• Secreted when [glucose] high --> increases rate of glucose transport into muscle and fat
• Stimulates glycogen synthesis in liver.



2. glucagon

• Protein secreted by Beta cells of pancreas.
• Operational under low [glucose].
• Restores blood sugar levels by stimulating glycogen degradation.



3. epinephrine

• Stimulates glycogen mobilization to glucose 1-phosphate --> glucose 6-phosphate.
• Increases rate of glycolysis in muscle and the amount of glucose in bloodstream.