Adrenergic receptors and synapses Flashcards
What molecules synthesise acetylcholine?
Choline + Acetyl coenzyme A
Catalysed by choline acetyltransferase
What molecules synthesise Noradrenaline?
Tyrosine + Tyrosine hydroxylase (limiting reagent) —> DOPA
DOPA + DOPA decarboxylase —> Dopamine
Dopamine + Dopamine beta-hydroxylase —> Noradrenaline
How does choline and tyrosine enter the synapses?
Na+ transporter (symporter)
What receptors does noradrenaline act on?
Adrenergic
What receptors does acetylcholine act on?
Muscarinic
Nicotinic
What type of receptors are nicotinic?
Ligand gated ion channels
What type of receptors are muscarinic?
GPCR
Where are adrenergic receptors found?
At the end of the post-ganglionic neuron for the sympathetic nervous system
Where are nicotinic receptors found?
At the ganglionic synapse for both the parasympathetic and sympathetic NS
Where are muscarinic receptors found?
At the end of the post-ganglionic neuron for the parasympathetic NS
Summarise how vMAT works and what its function is
Function = transporting NA into vesicles for transportation
Hydrolysis of ATP = H+ into vesicle
Proton pump = H+ out, NA in
What inhibits vMAT?
Reserpine
What is the consequence of reserpine?
NA not transported and released
Doesn’t act on adrenergic receptors
Sympathetic affects cant be produced
Decrease HR
Decrease in renin release
What causes Ca2+ to be released
Action potential - depolarisation = Ca2+ channels open
What type of channels are Ca2+
L-type voltage gated ion channels
Where does Ca2+ get released into?
Pre-synaptic terminal