How does glucagon influence glucose concentration in the blood?

Glucagon is a hormone that increases the level of glucose in the plasma. When the glucose levels are too low (which is called hypoglycemia), glucagon will be secreted by pancreas. (Insulin does the opposite – the pancreas secretes it when glucose levels are too high, i.e. hyperglycemia.)

How does glucagon work? The liver takes in the secreted glucagon, where it induces a signal cascade (a series of chemical signals that provoke a chain reaction). The purpose of this signal cascade is to increase the production of cyclic AMP, which activates protein kinase A. Protein kinase A will inhibit lipogenesis (production of fat) and glycolysis (the conversion of glucose to pyruvate, which reduces the overall amount of glucose), and instead it will induce gluconeogenesis (production of glucose). That glucose will then be transported across the plasma membrane of the liver cells and into the bloodstream.