autonomic receptors Flashcards
(21 cards)
what are the autonomic neurotransmitters ?
sympathetic - acetylcholine and norepinephrine
parasympathetic - acetylcholine
what does nerve depolarization lead to in terms of neurotransmitters ?
nerve depolarization leads to a calcium influx
which leads to the release of neurotransmitters
what is acetylcholine made from and how is it degraded ?
made from acetyl coA and choline
and degraded by AChE
what is the effect of botulinum toxin in the neurotransmitters ?
inhibit the release of acetylcholine in the synapses
what is norepinephrine synthesized from ?
tyrosine
where is doapmine made from ?
from tyrosine to DOPA to dopamine to norepinephrine
what is the MOA of amphetamines ?
increase dopamine and norepinehphrine activity in the CNS
they compete for reuptake transporters
what are the different receptor and what are the neurotransmitters associated with it ?
nicotinic and muscarinic receptors are both cholinergic receptors
nicotinic - acetylcholine
muscarinic - acetylcholine
adrenergic - alpha 1 and beta , used by norepinephrine
what type of receptors are nicotinic receptors ?
ligand gates ion channels
when the channels open they allow for entry into the target site \depolarization of target
what type of receptors are muscarinic and adrenergic receptors ?
G protein coupled receptors GDP and GTP
binding activity activates a second messenger
generally what are the 2 second messengers ?
cyclic AMP made by adenyl cyclase
inositol triphosphate 3 IP3 that is made by phospholipase C
what are the different subtypes of g protein coupled receptors ?
Gs, Gi, Gq
Gs - found in beta or beta 2 receptors
Gi - found in M2 receptors
Gq are found in the alpha 1 and M3 receptors
what is the function of the Gs subtype ?
they stimulate adenyly cyclase and raise intracellular cAMP levels which increases PKa activity and works on beta 1 and beta 2 receptors
what is the effect of cyclic AMP on the body ?
stimulates heart myocytes through the Gs receptors and Beta 1 receptors
relaxes vascular smooth muscles through beta 2 receptos
all beta rceptors have which type of receptors ?
Gs receptors - to increase the levels of cAMP
what is the function of the Gi receptor proteins ?
inhibit adenyly cyclase
decrease levels of cAMP and hence the levels of PKA
what receptors are associated with Gi coupled receptors ?
M2 these decrease cardiac myocytes
what is the function of the Gq subtype of g coupled receptors ?
generally associated wth contraction and secretion
they work by increasing the intracellular levels of IP3 through the activation of phospholipase C
what are the receptors associated with Gq receptors ?
alpha 1 and M3
what are the receptors associated with vascular smooth muscle contraction ?
Gq only
receptors for each g protein subtype :
Gq - HAVe 1 MM
H1 , V1 M1 M3
Gi - MAD2
M2 and alpha 2 and D2
Gs- everything else
