Respiratory Pharmacology Flashcards
Where are the cell bodies of preganglionic fibres found
In the brainstem
Where are the cell bodies of postganglionic fibres found?
Embedded in walls of bronchi and bronchioles
What does stimulation of postganglionic CHOLINERGIC fibres cause?
- bronchial smooth muscle contraction
2. Increased mucus secretion
What does stimulation of postganglionic NON-CHOLINERGIC fibres cause?
Bronchial smooth muscle relaxation
Where are the M3 muscarine ACh receptors which mediate smooth muscle contraction located?
Airway smooth muscle cells
Where are the M3 muscarine ACh receptors which mediate mucus secretion located?
gland/ goblet cells
What mediates bronchial smooth muscle relaxation in parasympathetic division?
NO and VIP (vasoactive intestinal peptide)
Sympathetic stimulation causes… (4 things)
- Bronchial smooth muscle relaxation
- Decreased mucus secretion
- Increased mucociliary clearance
- Vascular smooth muscle contraction
What mediates bronchial smooth muscle relaxation in sympathetic division?
B2-ADR on ASM cells (activated by adrenaline from adrenal glands)
What mediates vascular smooth muscle relaxation in sympathetic division?
A1-ADR on VSM cells
What mediates mucus secretion in sympathetic division?
B2-ADR on gland/ goblet cells
What mediates mucociliary clearance in sympathetic division?
B2-ADR on epithelial cells
Mucociliary escalator
Sweeps invading particles up towards oropharynx
Causes of asthma attacks
Allergens
Exercise (cold, dry air)
Resp infections
Smoke, dust etc.
Asthma
Recurrent, reversible obstruction to airways in response to substances that would not affect normal people
Pathological changes to bronchioles in asthma
Increased smooth muscle mass (hypertrophy and hyperplasia)
Oedema
Increased mucus secretion
Exposed sensory nerve endings due to epithelial damage
Sub-epithelial fibrosis
Cause of bronchial hyper responsiveness in asthma
Epithelial damage
2 phases of an asthma attack
Immediate (mainly bronchospasm; also acute inflammation)
Delayed (bronchospasm and delayed inflammation)
