nicotinic cholinergic synapse Flashcards
what is the role of vesamicol?
blocks transfer of ACh into vesicles
what is the role of batulinum toxin?
blocks the release of Ach from nerve ending
what is the role of anticholinesterases?
prevent the hydrolysis of ACh by enzyme acetylcholinesterases
what is the role of hemicholinium?
blocks uptake of choline by neuromuscular junction
n bm
kx,,what is noradrenaline?
neurotransmitter that plays a key role in the bodys sympathetic nervous system
where is noradrenaline synthesised and what is the rate limiting step
occurs in noradgrenic nerves, tyrosine hydroxylase is rate limiting step
where does noradrenaline act on?
adrenergic alpha and beta adrenoceptors
give 3 actions that happens when noradrernaline acts upon adrenergic receptors
increased heart rate + blood pressure
vasoconstriction
bronchodilation
what is the role of disulfram? (synthesis)
inhibits dopamine beta-hydroxylate, casuing depletion of NA stores
what is the role of reserpine? (storage)
blocks mechanism that transports NA into vesicles
what is the role of tyramine (amphetamine)? (release)
increase release of NA from vesicles
what is the role of nimodipine? (release)
reduces release by blockage of Ca2+ channels in nerve terminals
give 4 effects of alpha 1-adrenoceptors
- contraction of smooth muscle (blood vessel)
- relaxation of gut smooth muscle
- salivary secretion
- hepatic glycogenolysis
give 4 effects of alpha 2-adrenoceptors
- inhibition of transmitter release
- platelet aggregation
- contraction of vascular smooth muscle
- decreased insulin release
what is the effect of beta 1-adrenoceptor
increased heart rate
what is the 4 effects of beta 2-adrenocpetor?
- bronchodilation
- vasodilation
- muscle tremor
- relaxation of gut smooth muscle
what is the effect of beta 3-adrenocpetor
lipolysios
which adrenoceptors is adrenaline an agonists of? (epinephrine)
a1, a2, b1, b2
which adrenoceptors is noradrenaline an agonists of? (norepinephrine)
a1, a2, b1
which adrenoceptors is isoprenaline an agonists of? (isoproterenol)
b1, b2
give an agonist of alpha 1
phenylephrine
give an agonist of alpha 2
clonidine
give a b1-agonist
dobutamine (heart failure)
give a b2-agonists
salbutamol
give a non selective a-antagonist
phentolamine
give an a2-antagonist
yohimbine
give an a1-antagonist
prazosin
give a b1-antagonists
atenolol
give a non-selectibe b-antagonist
propranolol
give a b2-antagonist
butaxamine