Glucagon W3

Question 1

What is glucagon

Answer 1

Raise his blood glucose when it drops too low

Peptide hormone made by alpha cells of the pancreas in the islet of Langerhans

Glucagon = glucose is gone

Question 2

How many amino acids does it have

Answer 2

31

Question 3

How does it act

Answer 3

Binds to G-protein coupled receptors on liver cells

This activates adenyl cyclase which converts ATP to CAMP

CAMP activates protein kinase A

PKA triggers a cascade that leads to increased glucose

Question 4

When is it secreted

Answer 4

Secretion is triggered by low blood glucose, high amino acid levels, exercise

Question 5

Target organ

Answer 5

Liver

Is secreted into hepatic portal vein

Question 6

What does it promote (liver and adipose tissue)

Answer 6

In the liver:
- Glycogenolysis
- Gluconeogenesis
- ketogenesis
- Beta oxidation

In adipose tissue :
- Lipolysis

Question 7

Effects on carb metabolism

Answer 7

Increase blood sugar, glycogenolysis and gluoneogenesis

Decrease glycoeenesis

Question 8

Effect on at metabolism

Answer 8

Increase level of fatty acids in bloood and lipolysis

Decrease triglyceride synthesis

Question 9

Effects on protein metabolism - liver sonly

Answer 9

Increase proteolysis in liver

Decrease protein synthesis in liver

No significant effect on blood amino acid level