Reactive hypoglycemia In contrast, the hormone glucagon is released by the pancreas as a response to lower than normal blood sugar levels. Glucagon initiates uptake of the stored glycogen in the liver into the bloodstream so as to increase glucose levels in the blood. Sporadic, high-carbohydrate snacks and meals are deemed the specific causes of sugar crashes. The “crash” one feels is due to the rapid increase and subsequent decline of blood sugar in the body system as one begins and ceases consumption of high-sugar foods. More insulin than is actually needed is produced in response to the large, rapid ingestion of
Glucose 6-phosphate and muscles in the form of glycogen for most multicellular animals, and in intracellular starch or glycogen granules for most other organisms. Within a cell, glucose 6-phosphate is produced by phosphorylation of glucose on the sixth carbon. This is catalyzed by the enzyme hexokinase in most cells, and, in higher animals, glucokinase in certain cells, most notably liver cells. One equivalent of ATP is consumed in this reaction. The major reason for the immediate phosphorylation of glucose is to prevent diffusion out of the cell. The phosphorylation adds a charged phosphate group so the glucose 6-phosphate cannot easily cross the