What effect does glucagon have on blood glucose levels?

Glucagon is a hormone produced by the alpha cells of the pancreas that plays a critical role in regulating blood glucose levels, especially during periods of fasting or low carbohydrate intake. When blood glucose levels drop, glucagon is released into the bloodstream and acts primarily on the liver. It stimulates the liver to convert stored glycogen into glucose through a process called glycogenolysis. Additionally, glucagon promotes gluconeogenesis, which is the synthesis of glucose from non-carbohydrate sources, further increasing the availability of glucose in the bloodstream.

As a result, the primary effect of glucagon is to raise blood glucose levels, making it essential for maintaining energy balance and ensuring that the body has adequate glucose supply between meals or during energy expenditure. This is particularly important for the brain and other organs that rely heavily on glucose as their main energy source.