Al-Mehdi CV-ANS Pharm Flashcards
baroreceptor control via carotid sinus and aortic arch respond to what
stretch
carotid _____ senses stretch
sinus
carotid ____ senses oxygen
body
nucleus in brain that is collector of all visceral input
NTS
nucleus in brain that provides only motor supply of the heart
Nucleus Ambiguus
the carotid sinus branch of what nerve goes to NTS then nucleus ambiguus to provide action of heart in response to increased or decreased stretch
carotid sinus branch of CN IX (glossopharyngeal)
nerve that is primary sensor for oxygen in carotid body
vagus n.
for baroreceptor of carotid sinus, when do the afferents fire
when MAP goes up OR down
for baroreceptor of aortic arch, when do afferents fire
only when MAP goes up
normal tension where there is no firing from carotid sinus or aortic arch
MAP of 85
what happens when MAP drops from 85 to 60 (hypotension)
firing at carotid sinus to NTS then CVLM, RVLM, to IML and send NE to B1(Gs) on SA, AV, and myocardium
what happens when MAP increases from 85 to 120
firing at both carotid sinus and aortic arch to NTS, signal relayed to Nucleus Ambiguus to vagus to slow down HR (mainly has Ach binding to M2 (Gi) on SA node)
main receptor and activity of NE
a1 (constriction/contraction)
activates all receptors equally
Epi
products of adrenal medulla
Epi and NE
NE when bound to a2 (Gi) on presynaptic side
inhibitory effects
Clonidine
alpha-methyldopa
tizanidine
agonists that bind a2 and inhibit NE activity
NE when bound to a1 (Gq) on postsynaptic side
activation (contraction)
NE when bound to B1 (Gs) on postsynaptic side
activation (contraction)
is body more worried about lower bp or higher bp
lower bp (hypotension)
coronary, carotid, skeletal, and hepatic vascular beds have too much _____ receptors (so will usually dilate)
B2
these cells make renin that increases aldosterone and ultimately causes increase Na+ and increase in blood volume
juxtaglomerular cells
PDE inhibitor that allows for increase in contractility
MILRINONE
drug that decreases venous tone and reduces preload of heart
morphine
used to decrease blood volume by eliminating water
diuretics
part of heart highly responsive to emotional states
SA node
only innervation to blood vessels
sympathetic
rich in beta2 (dilation)
coronary arterioles
contain a1 receptors; can precipitate MI
coronary arteries
2 main drugs used to treat orthostatic hypotension
MIDODRINE (a1 agonist)
DROXIDOPA (precursor of NE)
this is seen when putting on a tie; carotid sinus sends signal to brain saying high bp and then body lowers bp and person faints
carotid sinus syndrome
B1 stimulation effect on SA, AV, and myocardium:
SA: + Chronotropy (rate)
AV: + Dromotropy (conduction speed)
myocardium: + inotropy (contractility)
SA node M2 stimulation
- chronotropy (decrease rate)
alpha (a1 and a2) receptors are activated more by what
NE
NE stimulation can inhibit what
Ach from being released when NE binds a2 on same neuron and neighbor
Ach stimulation can inhibit what
NE being released when Ach binds M2 on same neuron and neighbor
neuropeptide Y (NPY) can inhibit what neurotransmitter release
Ach
released from cholinergic terminal and causes vasodilation
VIP
long acting form of VIP for HTN
VASOMERA
these specific neurons modulate parasympathetic ganglion cells
NANC
released from NANC neurons
substance P and CGRP
2 main effects of parasympathetic system on heart
rate and rhythm (- chronotropy and - dromotropy)
____ node propagation depends on Ca2+ current
AV node
drug that is used to treat bradycardia; competitive antagonist at M2 receptor
Atropine
Why does calcium after contraction need to be picked up back into SR?
in order to depolarize again, muscle MUST repolarize and relax for next contraction to occur
vascular smooth muscle relaxation by B2 (Gs)
increase cAMP, increase PKA, causes MLCK phosphorylation, decrease Ca2+/calmodulin, relaxation
one of the most important drugs used to restore heart beat after cardiac arrest
Epinephrine
limit ___ agonists to treat shock due to decreasing energy efficiency
B1
with_____ sympathetic activation will increase O2 demand (but will end up with O2 supply/demand mismatch)—>shock
MI
what ultimately results in referred pain for cardiac pain
convergence of interneuron (crossover)
oxygen sensors
carotid and aortic bodies
receptors responsible for sensing dyspnea (lack of O2)
J receptors (juxta-capillary)
