Endocrine Pancreas

Question 1

Normal range [BG]

Answer 1

4.2 - 6.3

Question 2

Obligatory glucose utilising tissues

Answer 2

Can only use glucose for energy

- Brain

Question 3

[BG] maintained

Answer 3

• Glycogenolysis

- Gluconeogenesis

Question 4

Islet cells: 4 types

Answer 4

• Alpha: glucagon
• Beta: insulin
• Delta: somatostatin
• F: pancreatic polypeptide

Question 5

Insulin production

Answer 5

Peptide hormone produced by B cells.

• Preproinsulin
• Proinsulin
• Insulin and C-peptide

Question 6

Stimulation of insulin secretion

Answer 6

Increased [BG] and [AA]
Glucagon
Incretin hormones
Vagal nerve activity

Question 7

Insulin secretion mechanism

Answer 7

Glu through GLUT, ATP increases, K channel closes, intracellular K increases, depolarisation, Ca channels open, stimulation of insulin vesicle exocytosis into circulation.

Question 8

Function of insulin

Answer 8

Decrease [BG]

• Increase glycogen synthesis, AA uptake, lipogenesis and K entry
• Decreases lipolysis and gluconeogenesis

Question 9

Insulin mechanism of action

Answer 9

Binds to tyrosine kinase receptors of insulin-sensitive tissue. Stimulates mobilisation of GLUT-4 to cell membrane.

Question 10

Inhibition of insulin secretion

Answer 10

• Low BG
• Somatostatin (GHIH)
• Sympathetic a2 effects
• Stress

Question 11

Excess glucose converted to

Answer 11

• Glycogen in liver and muscle

- Triacylglycerols in liver and adipose tissue

Question 12

Excess AA converted to

Answer 12

• Fat

Question 13

Excess fatty acids converted to

Answer 13

• Triglycerides in liver and adipose tissue

Question 14

Glucagon production

Answer 14

Peptide hormone produced by pancreatic alpha cells

Question 15

Stimulation of glucagon secretion

Answer 15

Decreased [BG] 
Increased plasma [AA]
Sympathetic innervation
Cortisol
Stress (exercise)

Question 16

Function of glucagon

Answer 16

Increase BG

- Increased glycogenolysis, glucogenesis (from AA’s) and ketogenesis (from FFA’s)

Question 17

Glucagon mechanism of action

Answer 17

• G-protein coupled receptors linked to cAMP system which when activated phosphorylate specific liver enzymes.

Question 18

Inhibition of glucagon secretion

Answer 18

• Glucose
• Free fatty acids and ketones
• Insulin
• Somatostatin

Question 19

Somatostatin

• Function
• Effect on insulin/glucagon

Answer 19

Peptide hormone produced by D cells and hypothalamus.

• Inhibit GI activity (secreted in response to [BG] and [AA] elevations
• Suppress insulin/glucagon

Question 20

Exercise affect on glucose metabolism

Answer 20

• Increases glucose entry and insulin sensitivity

Question 21

Starvation affect on glucose metabolism

Answer 21

• Body converts excess FFA’s to ketone bodies

Question 22

Type I diabetes

Answer 22

Autoimmune destruction of pancreatic B cells.

- Cannot produce insulin and so cannot absorb glucose

Question 23

Type II diabetes

Answer 23

Reduced sensitivity to insulin

- Abnormal response or decrease in number of insulin receptors

Question 24

Diabetes diagnosis

Answer 24

Glucose tolerance test

Question 25

Diabetes complications

Answer 25

retinopathy, neuropathy, nephropathy, CV disease

Question 26

DKA

Answer 26

• Lack of insulin results in lack of ketone body uptake

- Metabolic acidosis