Glycogenolysis

[1] In the muscles, glycogenolysis begins due to the binding of cAMP to phosphorylate kinase, converting the latter to its active form so it can convert phosphorylase b to phosphorylase a, which is responsible for catalyzing the breakdown of glycogen.

[1] Glycogenolysis takes place in the cells of the muscle and liver tissues in response to hormonal and neural signals.

In particular, glycogenolysis plays an important role in the fight-or-flight response and the regulation of glucose levels in the blood.

[4] In myocytes, glycogen degradation may also be stimulated by neural signals;[5] glycogenolysis is regulated by epinephrine and calcium released by the sarcoplasmic reticulum.

[3] Parenteral (intravenous) administration of glucagon is a common human medical intervention in diabetic emergencies when sugar cannot be given orally.