Glycogen many respects serves as a countersignal to insulin. In response to insulin levels being below normal (when blood levels of glucose begin to fall below the normal range), glucagon is secreted in increasing amounts and stimulates both glycogenolysis (the breakdown of glycogen) and gluconeogenesis (the production of glucose from other sources). Muscle cell glycogen appears to function as an immediate reserve source of available glucose for muscle cells. Other cells that contain small amounts use it locally, as well. As muscle cells lack glucose-6-phosphatase, which is required to pass glucose into the blood, the glycogen they store is available solely
Glycogen-branching enzyme deficiency Glycogen-branching enzyme deficiency Glycogen-branching enzyme deficiency (GBED) is an inheritable glycogen storage disease affecting American Quarter Horses and American Paint Horses. It leads to abortion, stillbirths, or early death of affected animals. Glycogen is a molecular polymer of glucose used to store energy. It is important for providing energy for skeletal and cardiac muscle contraction, and for maintaining glucose hemostasis in the blood. Molecules of glucose are linked into linear chains by α-1,4-glycosidic bonds. Additionally, branches of glucose are formed off of the chain via α-1,6-glycosidic bonds. 2 molecules of glucose are joined into an α-1,4-glycosidic bonds by an enzyme