MP324 - ASTHMA

Question 1

types of stimuli

Answer 1

exercise
cold air
hyperventilation
chemical agents
allergies
aspirin

Question 2

inflammatory cells of asthma

Answer 2

eosinophils
mast cells
neutrophils

Question 3

smooth muscle responsiveness in asthma

Answer 3

hyper-responsiveness of smooth muscle to substances that cause contraction of the smooth muscle, such as acetylcholine, histamine and PAF

hypo-responsiveness of the smooth muscle to substances that relax smooth muscle, such as adrenaline

Question 4

airway changes in asthma

Answer 4

bronchial smooth muscle contracts to narrow the airway lumen, making it harder to breath.

the smooth muscle undergoes proliferation (hyperplasia) and the cells enlarge (hypertrophy) as well as contracting becomes ‘synthetic’ (produce inflammatory mediators that cause bronchoconstriction)

Question 5

goblet cells in asthma

Answer 5

goblet cells produce excessive mucus secretion (oedema) that cause an obstructive plug, making it more difficult to breathe

Question 6

phenotypes of the lungs due to bronchial asthma

Answer 6

• lungs are over-distended due to over-inflation
• small area of atelectasis (part of lung is dead)
• occlusion of bronchi and bronchioles by thick tenacious mucous plug

Question 7

structural changes

Answer 7

epithelial damage
mucosal oedema
increased intraluminal secretions
basement membrane thickening
smooth muscle hypertrophy
hyperplasia
inflammation

Question 8

changes in receptors as a result of asthma

Answer 8

• higher amount of Rho kinase due to cytokine-mediated gene induction (more sustained contraction)
• higher levels of M3 receptors
• higher levels of signalling components

Question 9

neuronal imbalance in asthma

Answer 9

• autonomic imbalance
• reduced adrenergic receptors on the bronchial smooth muscle, making it hypo-responsive to adrenaline
• increased cholinergic drive, releases of acetylcholine (bronchoconstrictor)

Question 10

what doesn’t work for asthma?

Answer 10

NSAIDs
antihistamines (H1)