Endocrine pancreas

Question 1

Which hormones are glucose counter-regulatory hormones? Describe their effect on glucose

Answer 1

Adrenaline
Glucagon
Cortisol
Growth hormone

These hormones raise the level of glucose in the blood by promoting catabolic processes including glycogenolysis, gluconeogenesis and ketogenesis. This protects the body from hypoglycaemia.

Question 2

Why is thyroid hormone not a glucose counter-regulatory hormone?

Answer 2

Thyroid hormones increase blood glucose levels but they also stimulate insulin release, so overall the glucose levels stay constant.

Question 3

What is the normal range of blood glucose concentration?

Answer 3

4.2 - 6.3mM (80 - 120 mg/dl)

Question 4

What is the threshold for hypoglycaemia?

Answer 4

[BG] < 3mM

Question 5

Which cells in the pancreas produce glucagon?

Answer 5

alpha-cells

Question 6

Which cells in the pancreas produce insulin?

Answer 6

beta-cells

Question 7

Which cells in the pancreas produce somatostatin?

Answer 7

delta-cells

Question 8

Which cells in the pancreas produce pancreatic polypeptide?

Answer 8

F-cells

Question 9

Which part of the pancreas is endocrine?

Answer 9

Islets of Langerhans

Question 10

Which body tissues require insulin to take up glucose?

Answer 10

muscle and fat

Question 11

Describe the function of the GLUT-1 transporter

Answer 11

Basal glucose uptake in the brain, kidney and RBCs

Question 12

Describe the function of the GLUT-2 transporter

Answer 12

Insulin-independent transporter in the liver and the pancreatic b-cells

Question 13

Describe the function of the GLUT-4 transporter

Answer 13

Insulin-dependent transporter in the cytoplams of muscle and adipose cells.
Insulin binds to tyrosine receptors on the cell membrane. This stimulates GLUT-4 to migrate to the membrane so that it is able to transport glucose into the cell.

Question 14

Which organ is the primary target of glucagon?

Answer 14

The liver