Blood glucose levels are regulated by several hormones ~ Insulin, Glucagon, Epinephrine, Cortisol, and Growth hormone. Insulin promotes Glycogen synthesis, fat storage in the form of Triglycerides, and cellular uptake of blood glucose. Glucagon, Epinephrine, Cortisol, and Growth hormone all cause Glycogen breakdown and stimulate conversion of Amino acids to glucose. Persistent elevations of these hormones can lead to hyperglycemia (high blood sugar.) Glucagon breaks down Liver Glycogen stores to release glucose into the blood stream and it prevents the normal storage of extra glucose into Glycogen and Triglycerides. Glucagon has no effect on Muscle Glycogen. Epinephrine is very important during times of stress, including acute illnesses/infections, trauma etc. It causes increased glucose levels in the blood stream to ensure adequate glucose reaches brain cells. It stimulates the breakdown of muscle glycogen to raise blood glucose.