Glucose homeostasis: Glucagon Flashcards
What are antagonistic hormones?
Antagonistic hormones are a pair of hormones that have opposing effects on one another.
Why are Insulin and Glucagon antagonistic hormones?
Because insulin works to lower blood glucose levels while glucagon works to raise blood glucose levels.
What can Glucagon be used for therapeutically?
In the treatment of insulin-induced hypoglycaemia.
Glucagon is made up of how many amino acids?
31 amino acid peptide hormone
Glucagon acts by the stimulation of which receptor?
A cell surface G-protein-coupled-receptor. This increases cAMP within the cell (G-alpha-s)
When is glucagon secreted?
Secreted during times of fasting (between meals) by alpha-cells of the islets of Langerhans
- Glucose decreases = Secretion increases
Which is the major target organ for glucagon?
The liver is the major target organ. Its secreted into the hepatic portal vein.
What does glucagon promote?
It promoted the breakdown of energy stores, raising the level of energy sources in the blood.
What effects does Glucagon have on carbohydrate metabolism?
- Increases blood sugar
- Increases Glycogenolysis
- Decreases Glycogenesis
- Increases Gluconeogenesis
What effects does Glucagon have on fat metabolism?
- Increased levels of fatty acids in blood
- Increases Lipolysis
- Decreases Triglyceride synthesis
What effects does Glucagon have on protein metabolism - (Liver only)
- Increases Proteolysis (In the liver)
- Decreases Protein synthesis (In the liver)
- No significant effects on blood amino acid level as no effect of skeletal muscle.
