Endocrine Pancreas

Question 1

What are the three main cell types in the pancreas

Answer 1

alpha, beta and delta cells

Question 2

alpha cells in the pancreas secrete ______

Answer 2

glucagon

Question 3

beta cells in the pancreas secrete

Answer 3

insulin and amylin

Question 4

delta cells in the pancreas secrete

Answer 4

somatostatin

Question 5

All the cells of the exocrine pancreas are located in which area

Answer 5

Islets of Langerhans

Question 6

alpha cells are situated mainly in which area of the Islets of Langerhans

Answer 6

Core

Question 7

Which glucose transporter is insulin dependent

Answer 7

GLUT4

Question 8

Which glucose transporter is insulin independent

Answer 8

GLUT2

Question 9

What effect does insulin have in the liver

Answer 9

• increased glycolysis
• increased protein synthesis
• increased amino acid uptake

Question 10

What effect does insulin have in adipose

Answer 10

• inhibits hormone sensitive lipase
• promostes lipogenesis through lipoprotein lipase
• inhibits ketogenesis

Question 11

What effect does insulin have in muscle

Answer 11

• increased glucose uptake
• increased glycogenesis
• increased protein synthesis
• increased amino acid uptake

Question 12

What effect does glucagon have in the liver

Answer 12

• increased gluconeogenesis

- increased glycogenolysis

Question 13

What effect does insulin have in adipose

Answer 13

-increases lipolysis

Question 14

Effects of insulin deficiency on protein metabolism

Answer 14

• Less protein synthesis hence blood amino acid levels rise
• Amino acids catabolism is increased.
• Increased gluconeogenesis

Question 15

Effects of insulin deficiency on fat metabolism

Answer 15

• Liver and other tissues the fatty acids are catabolized to acetyl-CoA.
• Some acetyl-CoA are catabolized (supply is ˃ than utilization)
• Excess acetyl-CoA is converted to ketone bodies
• Plasma concentration of TG, chylomicrons and FFA ↑and plasma is lipemic
• Plasma cholesterol level is ↑

Question 16

How does insulin deficiency on fat metabolism

Answer 16

Increase in ketone bodies causes ketoacidosis

Question 17

Characteristics of Type I diabetes mellitus

Answer 17

• insulin dependent
• destruction of beta cells
• usually starts in childhood

Question 18

Characteristics of Type II diabetes mellitus

Answer 18

• insulin independent

- decreased secretion of insuiln

Question 19

Why can obesity lead to Type II disbetes mellitus

Answer 19

Excess in take of food cause a continuous increase in insulin secretion which causes a down regulation of insulin receptors

Question 20

What is the main stimulus for insulin release

Answer 20

glucose

Question 21

Incretin has an effect on which organ

Answer 21

Intestine

Question 22

Proinsulin is composed of what

Answer 22

An A chain, B chain and a C peptide

Question 23

What is the clinical significance of C-peptide in insulin

Answer 23

It allows us to get an estimate of how much insulin in secreted from the beta cells

Question 24

The B chain in insulin has receptor tyrosine kinase activity that leads to activation of which two second messenger pathways

Answer 24

PI3K and MAPK

Question 25

Akt (PKB) activates what

Answer 25

• GLUT4 translocation
• protein phosphatases
• SREBP1C

Question 26

How does amylin aid in Type II diabetes mellitus

Answer 26

amylin builds up in the beta cells and causes destruction of the cells

Question 27

Proglucagon is converted into which two substances

Answer 27

Glucagon and Glucagon-like-peptide 1

Question 28

Which stimulus increases Glucagon-like-peptide 1

Answer 28

Increased intestinal glucose

Question 29

Glucagon is inhibited by

Answer 29

1. hyperglyemia

2. somatostatin

Question 30

Glucagon is activated by

Answer 30

1. hypoglycemia
2. epinephrine
3. vagal stimulation