Glycogen and Blood Glucose

Hargreaves, M., 1997. Interactions between muscle glycogen and blood glucose during exercise. Exercise and Sport Sciences Reviews 25 21-39. 

Murphy SD, Porter S. 1966. Effects of toxic chemicals on some adaptive liver enzymes, liver glycogen, and blood glucose in fasted rats. Biochem Pharmacol 15 1665-1676. 

A. By 2-3 hours after a high-carbohydrate meal, the patient s glycogen stores would be filled. Glucagon would stimulate glycogenolysis, and blood glucose levels would rise. 

C. Thirty hours after a meal, liver glycogen is normally depleted, and blood glucose is maintained solely by gluconeogenesis after this time. However, in this case, a key gluco-... 

Glycogen is not as reduced as fatty acids are and consequently not as energy rich. Why isn t all excess fuel stored as fatty acids rather than as glycogen The controlled release of glucose from glycogen maintains blood-glucose levels between meals. The circulating blood keeps the brain supplied... 

Fig. 47.11. Production of blood glucose by the liver from various precursors during rest and during prolonged exercise. The shaded area represents the contribution of liver glycogen to blood glucose, and the open area represents the contribution of gluconeogenesis. From Wahren J, et al. In Howald H, Poortmans JR, eds. Metabolic Adaptation to Prolonged Physical Exercise. Cambridge, MA Birkhauser, 1973 148.

Storage and utilization of tissue glycogen, maintenance of blood glucose concentration, and other aspects of carbohydrate metabolism are meticulously regulated by hormones, including insulin, glucagon, epinephrine, and the glucocorticoids. 

---