Diabetes

Question 1

a) How is insulin secretion affected by ATP
b) What sort of intramolecular bonds does insulin have
c) What can breakdown of body fat lead to
d) What can be a complication of diabetes
e) What can drug therapy for diabetes cause

Answer 1

a) Elevated in response to an increase in intracellular ATP
b) Disulphide
c) Decreased blood pH
d) Damage to peripheral nerves
e) Hypoglycaemia

Question 2

a) In diabetes, in what tissues is glucose uptake impaired
b) On insulin stimulation, what happens to the insulin-stimulated glucose transporter
c) What hormone is involved in controlling appetite that is secreted by adipose tissue
d) Insulin changes the localisation of which integral membrane protein
e) What is a probable consequence if a type 1 diabetic injects too much insulin

Answer 2

a) Muscle and fat
b) GLUT4 translocates from an intracellular site to the plasma membrane
c) Leptin
d) GLUT4
e) Hypoglycaemia

Question 3

a) What is healthy range of BMI
b) Normal concentration of glucose (mM) range
c) What is the percentage that Na+/K+ ATPase contributes to basal metabolic rate
d) What protein involved in insulin signalling catalyses the phosphorylation of other proteins
e) What enzyme is activated as a consequence of insulin-induced dephosphorylation

Answer 3

a) 18.5 - 24.9
b) 4 - 7
c) 23%
d) Insulin receptor
e) Glycogen synthase

Question 4

a) Inhibition of what integral membrane protein leads to stimulation of insulin secretion
b) What enzyme phosphorylates glucose in pancreatic beta cells and liver
c) What enzyme activity is intrinsic to the intracellular portion of the insulin receptor
d) What is subject to mutation in malignant hyperthermia
e) What acute phase protein is synthesized by the liver in response to factors released by adipose tissue

Answer 4

a) ATP-sensitive potassium channel
b) Glucokinase
c) Protein tyrosine kinase
d) Ryanodine receptor
e) C reactive protein (CRP)

Question 5

a) What acts on the hypothalamus to stimulate feeding after secretion from stomach endocrine cells
b) What is a long-term complication of untreated diabetes
c) What is the underlying cause of type 1 diabetes

Answer 5

a) Ghrelin
b) Microvascular disease
c) Autoimmune destruction of pancreatic beta cells