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
Glucose some fat types and have other purposes. Glycogen is the body's "glucose energy storage" mechanism, because it is much more "space efficient" and less reactive than glucose itself. As a result of its importance in human health, glucose is an analyte in glucose tests that are common medical blood tests. Eating or fasting prior to taking a blood sample has an effect on analyses for glucose in the blood; a high fasting glucose blood sugar level may be a sign of prediabetes or diabetes mellitus. The glycemic index is an indicator of the speed of resorption and conversion to blood