pharmacology Flashcards
what controls the airways para or sympathetic
parasympathetic
is parasympathetic preganglionic Cholinergic or nitrergic
cholinergic
where do parasympathetic preganglionic fibres come from
brainstem
where do parasympathetic post ganglionic fibres act on
bronchioles
what are the neurotransmitters and receptors of the cholinergic fibres and what do they do
ACh and M3, M3 increases phospho C which converts IP2 to PIP3 which opens calcium channels
what are the neurotransmitters of the non-cholinergic fibres and what do they do
NO and VIP, dilation
what do sympathetic post ganglionic fibres act on
submucosal glands and smooth muscles of arterial vessels (a1)
what do sympathetic post ganglionic fibres act on, causing what to be released
adrenal glands, adrenaline
what receptors does adrenaline act on and what does this cause
B2, dilation, decreased mucous secretion, increased mucociliary clearance
which 2 ways can cause contraction in airway smooth muscle
hormonal (ACh on m3, causing IP3) and depolarisation (calcium influx), both cause Ca influx
how does calcium cause contraction
Ca binds to calmodium which activates myosin light chain kinase (MLCK), MLCK used ATP to phosphorylate MLC and myosin slides past actin
what caused relaxation of MLC
dephosphorylation of MLC by myosin phosphate (MP),
is asthma obstructive or restrictive and reversible or irreversible
obstructive, reversible
what are pathological changes of asthma
1) increased smooth muscle mass, 2) accumulation of interstitial fluid 3) increased mucous secretion 4) epithelial damage 5) sub epithelial fibrosis
What happens to FEV1 and peak flow in asthamtics
decrease
what causes hypersensitivity of airways
epithelial damage exposing nerve endings
what is the difference between mild and severe asthma
mild = hypersensitivity and minor hyperactivity, severe = hypersensitivity and hyper activity
why does hypersensitivity to an allergen mean
when allergen eg pollen is inhaled, there is a very strong immune inflammatory response
in non-atopic individuals what happens when pollen is inhaled
dendritic cell phagotyoses and TH0 cells produce TH1 (normally IgG
in atopic individuals what happens when pollen is inhaled
strong TH2 response, release interleukins (IL4) and activate B cells producing IgE
in severe asthma what T cells are involved
TH2 and TH1