Based on the context, it's likely the question is asking about the biological molecule Glucagon, often abbreviated as GCG. This is because the reference material focuses on Glucagon. Thus, this response will address Glucagon.
Glucagon (GCG) is a key hormone in biology, primarily known for its role in regulating blood glucose levels.
Glucagon: The Basics
Glucagon is a 29-amino acid peptide hormone produced by the alpha cells of the pancreas. It counteracts the effects of insulin. When blood glucose levels are low (hypoglycemia), glucagon is released to increase blood sugar levels.
How Glucagon Works:
- Glycogenolysis: Glucagon stimulates the breakdown of glycogen (stored glucose) in the liver, releasing glucose into the bloodstream.
- Gluconeogenesis: It promotes the synthesis of glucose from non-carbohydrate sources (like amino acids and glycerol) in the liver.
Key Facts about Glucagon:
- Source: Pancreatic alpha cells.
- Function: Increases blood glucose levels.
- Target Organ: Primarily the liver.
- Counteracts: Insulin.
- Species Similarity: Glucagon is highly conserved across species; the sequence is identical in humans, rabbits, rats, pigs, and cows.
Clinical Relevance
Dysregulation of glucagon secretion contributes to the development of diabetes. In individuals with diabetes, either glucagon secretion is inappropriately elevated, or the body becomes resistant to the action of glucagon, resulting in hyperglycemia. Medications targeting glucagon signaling are being investigated as potential treatments for diabetes.
