Christian de Duve glucagon was the major hormone influencing the breakdown of glycogen (glycogenolysis) in the liver, by which more sugars are produced in the blood. De Duve's original hypothesis that glucagon was produced by pancreatic alpha cells was proved right when it was demonstrated that selectively cobalt-damage alpha cells stopped producing glucagon in guinea pigs, and finally isolated the purified hormone in 1953, including those from birds. De Duve was the first to hypothesise that production of insulin to decrease blood sugar level stimulated the uptake of glucose in the liver, and that there is a balanced production of insulin and glucagon
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