Pathology of Diabetes Mellitus

Question 1

What cells produce insulin?

Answer 1

Beta islet cells

Question 2

Where is insulin secreted?

Answer 2

Blood in capillaries

Question 3

What happens when insulin binds to its receptor?

Answer 3

Drives insulin into adipose tissue

Question 4

Describe the glucose metabolism

Answer 4

Increased glucose, increased Insulin, increased Glucose uptake by cells, Decreased serum glucose

Question 5

What occurs in type 1 DM?

Answer 5

Body cannot distinguish its own cells from other cells which results in an autoimmune attack on B islet cells. This results in insulitis which results in B islet cell destruction

Question 6

What occurs when B islet cells are destroyed?

Answer 6

Insulin levels decrease and glucose levels increase

Question 7

What occurs in type 2 DM?

Answer 7

Decreased tissue sensitivity to insulin and inability to secrete v high levels of insulin

Question 8

How does increased visceral upper body fat result in Hyperinsulinaemia?

Answer 8

It increases free FA’s in blood which decreases insulin receptor activity. This decreases glucose cell entry which results in increased demand for insulin so pancreas creates more = HYPERINSULINAEMIA

Question 9

What contributes to type 2 DM development?

Answer 9

Central adiposity + numerous genes defective for high end insulin secretion = increased insulin and increased glucose levels

Question 10

How does type 2 DM accelerate atherosclerosis?

Answer 10

Glucose attaches to LDL and stops LDL from binding to receptors. LDL is not removed from the liver and lipids +LDL stay in blood –> HYPERLIPIDAEMIA–> Atherosclerosis