What is the primary pharmacological action of glucagon?

The primary pharmacological action of glucagon is to raise blood glucose levels by stimulating glycogenolysis. Glucagon is a hormone produced by the alpha cells of the pancreas and plays a crucial role in glucose metabolism. When blood glucose levels drop, glucagon is released into the bloodstream and acts primarily on the liver, where it promotes the breakdown of glycogen (the stored form of glucose) into glucose. This process increases the concentration of glucose in the bloodstream, counteracting hypoglycemia.

Glucagon's action is particularly important in maintaining energy levels and metabolic balance, especially during fasting or intense physical activity when blood sugar levels may fall. By facilitating glycogenolysis, glucagon ensures that the body has a readily available source of glucose for energy.