What role does glucagon play in the body?

Glucagon plays a crucial role in the body by stimulating the liver to release glucose into the bloodstream. This hormone is secreted by the alpha cells of the pancreas when blood glucose levels are low, which is essential for maintaining homeostasis. When glucagon is released, it promotes glycogenolysis, the process of breaking down glycogen stored in the liver into glucose, which is then made available to the body for energy. This increase in blood glucose levels helps to counteract hypoglycemia, ensuring that cells, particularly in the brain, have adequate energy.

The function of glucagon is often contrasted with that of insulin, which lowers blood glucose levels. While glucagon raises blood sugar levels during fasting or between meals, its primary target organs, such as the liver, respond to its signaling to ensure a steady supply of glucose is available, demonstrating its vital role in energy metabolism.