ALS Lecture 7 - Pharmacology of Airways Obstruction DONE Flashcards
classic asthma starts in
childhood
classic asthma gives
bronchoconstriction
classic asthma has a
double reaction
1st asthma response
starts after 15mins of allergen, ends in ~15mins without treatment
2nd asthma response
75% is late reaction, more difficult to treat
asthma is characterised by
eosinophils
label the diagram of asthma pathophysiology
done
asthma pathophysiology (5 steps)
- IgE directed against allergen
- IgE produced by B lymphocyte, sticks onto mast cells
- degranulation of mast cells and inflammatory mediators
4, bronchospasm, vasodilation, mucus secretion, oedema
asthma inflammation causes
mucus plugs to block airways
asthma histology of airway
filled with mucus, nuclei of inflammatory cells
eosinophils stain and how up
pink, stained with eosin
asthma medication types (5)
SABA, LABA, corticosteroids (inhaled), leukotriene receptor antagonist, combination inhalers
bronchoconstriction is mediated by
smooth muscle contraction, beta agonists reverse this
action of beta receptors on smooth muscle (3 steps)
- stimulated
- release cAMP
- relax smooth muscle
label the diagram of montelukast combined with a steroid affects the dual pathways of inflammation
done
short acting beta agonist (SABA) example
Salbutamol, 4-5hrs
long acting beta agonist (LABA) example
Salmetrol, Formoterol, 12-24hrs
leukotriene receptor antagonist MOA (2 steps)
- block leukotriene receptors
2. stop eosinophil recruitment
leukotriene receptor antagonist example
Montelukast
antimuscarinics MOA (3 steps)
- blocks activity of muscarinic ACh receptor
2. bronchial dilation, decreased secretions
long-acting muscarinic antagonist example
tiotropium
methylxanthines act as
bronchodilators, relax smooth muscle
methylxanthines are used in
asthma, COPD
methylxanthines MOA (5 steps)
- inhibits phosphodiesterase which usually degrades cAMP
- increased cAMP
- activates PKA
- inhibits TNF-alpha, leukotriene synthesis
- reduces inflammation and innate immunity
methylxanthine example
theophylline
label the diagram of MOA of steroids
done
steroids are very effective at getting rid of _______ as they ____ ______
eosinophils, cause apoptosis
corticosteroids MOA (5 steps)
- attaches to and activates receptor
- receptor forms dimer
- dimer acts on DNA
- up regulates beta-receptor gene = more beta receptors
- down regulating cytokine genes = less inflammation
only ____ inflammation responds to _____
eosinophilic, steroids
oral steroids used to be given but
give lots of side effects
side effects of oral steroids
cushing’s syndrome
50-70% of inhaled steroids end up
in stomach
inhaled steroids don’t give side effects as they are
metabolised on first pass through liver so don’t get into systemic circulation
if patient is non-responsive to steroids, this may be due to (3)
poor compliance, poor technique, misdiagnosis
label the diagram of omalizumab
done
omalizumab blocks
IgE
IL-5 from innate lymphocyte also calls in
eosinophils
IL-5 blockers are injectable treatments used in _____ _____ with _____ _____
severe asthmatics, eosinophilic reaction
label the diagram of IL-5 blockers
done
label the triangle
done
copd includes
emphysema, chronic bronchitis
2 phenotypes of COPD patients
- pink puffers, mostly emphysema
- blue bloaters, mostly chronic bronchitis, neutrophilic inflammation so no steroid respsonse
eosinophilic bronchitis responds to
steroids
label the spirometry graph
done
to differentiate between eosinophilic and neutrophilic airway inflammation, look at the
full blood count
blood eosinophils above ___ indicate ______ ______ ______
0.3, steroid responsive disease
