Adrenergic Drugs Flashcards
what produces a physiological response as that of endogenous mediators
adrenergic agonist
which adrenergic agonist acts through stimulation of adrenergic receptors
direct action
which adrenergic agonist produces a response through the release of catecholamines from adrenergic neurons
indirect action
what are the 3 receptors of the adrenergic neurotransmission pathway
alpha
beta
alpha-2
what is the purpose of the alpha-2 adrenergic receptors in the adrenergic neurotransmission pathway
provide negative feedback to control the release of norepinephrine
what neurotransmitter is released in the adrenergic neurotransmission pathway
norepinephrine
what does the norepinephrine of the adrenergic neurotransmission pathway originate from (think neurotransmitter)
dopamine
what process is used to change dopamine into norepinephrine
hydrolyzation
what triggers the release of the norepinephrine from the neuron in the adrenergic neurotransmission pathway
change in cell membrane potential (action potentials) / influx of Ca++
which neurotransmitters are involved with adrenergic receptors
norepinephrine & epinephrine
what types of receptors are associated with adrenergic receptors
alpha & beta
which adrenergic receptors have a slightly higher affinity for epinephrine over norepinephrine
beta 2 and alpha receptors
which adrenergic receptor has an equal affinity for epinephrine and norepinephrine
beta 1
where are alpha-1 receptors found
post synaptic membrane of effector organs
where can alpha-2 receptors be found
- pre-synaptic
- post synaptic in beta cells of pancreas and blood vessels
what G protein is associated with alpha 1 receptors
Gq
what G protein is associated with alpha-2 receptors
Gi
which G protein is associated with beta receptors
Gs
what enzyme is used in addition to G protein Gq
Phospholipase C
what is the result of Gq acting on an alpha-1 receptor
smooth muscle contraction
what is the result of the activation of Phospholipase C
IP3 –> Ca++ release
what is the result of Gi acting on the Alpha-2 receptor
decrease adenylyl cyclase
decrease cAMP
if there is an inhibitory effect on alpha-2 receptor, what is the outcome
smooth muscle contraction / vasoconstriction
what is the result of the activation of beta receptor with Gs
heart muscle contraction
smooth muscle contraction
glycogenolysis
what stops the functions of the alpha-2 receptor
dephosphorylation
what adrenergic receptor is critical in controlling blood pressure
Beta-1
which beta receptor has a higher affinity for epinephrine
beta-2
where are beta-1 receptors often found
heart
kidney
fat cells
True or False:
Beta-1 receptors have an equal affinity for epinephrine and norepinephrine
true
where are Beta-2 receptors mostly found
blood vessels of skeletal muscle
liver
smooth muscles of bronchus
IG tract
uterus
what tissue/ organ does B1 receptors affect
cardiac
if there is an increase of epinephrine on a B1 receptor in the cardiac tissue, what is the result
increased HR
increased contractibility
increased cardiac output
what is the effect of norepinephrine on a B1 receptor in cardiac tissue
increased HR followed by a decrease in HR caused by vagal stimulation
True or False:
There will be an increase in heart contractibility in the presence of norepinephrine in the cardiac tissue
true
what receptor is mainly in charge of blood pressure
B1
why does diastolic pressure see little to no change in the presence of epinephrine on B1 receptors in cardiac tissue
B2 receptors = relaxation
norepinephrine has a greater affinity on B2 receptors
why does diastolic pressure see little to no change in the presence of epinephrine on B1 receptors in cardiac tissue
B2 receptors = relaxation
norepinephrine has a greater affinity on B2 receptors
what receptors create constriction of the blood vessels in the presence of epinephrine
alpha 1
alpha 2
what receptors cause dilatation of the blood vessels in splanchic and skeletal muscles in the presence of epinephrine
alpha 1
alpha 2
beta 2
what is the response of alpha 1 & 2 receptors of the blood vessels in the presence of norepinephrine
constriction
what receptor is caused bronchial dilation / relaxation in the presence of epinephrine
beta 2
how does beta 2 receptors in the respiratory tract response to norepinephrine
no response
what is the function of alpha 1, alpha 2, and beta 2 receptors in the GIT with epinephrine
relaxation
with the GI tract, what receptor is responsible for contraction of the sphincter muscle with epinephrine
alpha 1
True or False:
both epinephrine and norepinephrine cause constriction of the sphincter muscles of the GI tract with an A1 receptor present
true
what receptors are found in the urinary bladder
Beta 2
Alpha 1
where is the beta 2 receptor found in the urinary bladder
detrusor muscle