Glucagon isn't actually stored in the same way that glycogen (a stored form of glucose) is stored in the liver and muscles. Instead, glucagon is a hormone produced and released on demand.
Glucagon Production and Release
- Location: Glucagon is produced by alpha cells located within the islets of Langerhans in the pancreas. These islets are small clusters of cells within the pancreas.
- Release Mechanism: When blood glucose levels drop too low, the pancreas releases glucagon into the bloodstream. This hormone then signals the liver to break down glycogen into glucose, raising blood sugar levels.
Understanding the Difference: Glucagon vs. Glycogen
It's crucial to distinguish between glucagon and glycogen:
- Glucagon: A hormone that regulates blood sugar levels. It is not stored but produced as needed.
- Glycogen: A storage form of glucose, primarily found in the liver and muscles.
Think of it like this: glycogen is the pantry where glucose is stored, and glucagon is the key that unlocks the pantry when glucose is needed.
The Role of the Liver
The liver plays a vital role in the process:
- Glycogen Storage: The liver stores significant amounts of glycogen.
- Glucagon's Effect: When glucagon is released, it acts on the liver, triggering the breakdown of glycogen and releasing glucose into the bloodstream.
Therefore, while glucagon itself isn't stored, its effects are primarily seen in the liver, which houses the glycogen stores that glucagon helps mobilize.
