Homeostasis the same metabolic pathways as are used by the liver) and then stored in those fat cells together with the VLDL-derived triglycerides that were made in the liver. Muscle cells also take glucose up through insulin-sensitive GLUT4 glucose channels, and convert it into muscle glycogen. A fall in blood glucose, causes insulin secretion to be stopped, and glucagon to be secreted from the alpha cells into the blood. This inhibits the uptake of glucose from the blood by the liver, fats cells and muscle. Instead the liver is strongly stimulated to manufacture glucose from glycogen (through glycogenolysis) and from non-carbohydrate
PYGL glycolysis and other biosynthetic functions for energy metabolism. As the major isozyme in liver, PYGL is responsible for maintaining blood glucose homeostasis by regulating the release of glucose 1-phosphate from liver glycogen stores. One model suggests that Ca oscillations play a role in activating glycogen phosphorylase in glycogen degradation in liver cells. Through its function in the liver, PYGL is also central to meeting the glycemic demands of the entire body. Though other tissues may express all three forms in different proportions, the purpose of expressing multiple glycogen phosphorylases remains unclear. PYGL has been implicated in glycogen storage disease type