Autonomic Pharmacology Flashcards
1
Q
what is the goal of autonomic nervous system
A
keep homeostasis
2
Q
main neurotransmitter(s) of SNS
A
norepi and epi
3
Q
main neurotransmitter(s) of PNS
A
acetylcholine
4
Q
what is the other term for sympathomimetics
A
adrenergic agents, they boost SNS
5
Q
what is the other term for sympatholytics
A
adrenergic antagonists, they block SNS
6
Q
what is the other term for parasympathomimetics
A
Cholinergic agents, they boost PNS
7
Q
what is the other term for parasympatholytics
A
anticholinergics, they block PNS
8
Q
what is the process of catecholamines
A
they bind adrenergic receptors which causes a cascade of intracellular events that prepare the body for rapid response to stress
9
Q
what is the main synthesis location of catecholamines
A
adrenal medulla (chromaffin cells) and sympathetic nerve endings
10
Q
tyrosine is converted to ____ by the enzyme ____
A
L-Dopa, tyrosine hydroxylase
11
Q
L-Dopa is converted to ____ by the enzyme ____
A
Dopamine, DOPA decarboxylase
12
Q
Norepinephrine is converted to _____ by the enzyme ____
A
epinephrine, PNMT (phenylethanolamine N-methyltransferase)
13
Q
Dopamine is converted to ____ by the enzyme ____
A
norepinephrine, dopamine beta-hydroxylase
14
Q
what is the role of monoamine oxidase
A
converts dopamine, epi, and norepi into inactive metabolites
15
Q
what is the role of catechol-O-methyltransferase
A
adds a methyl group to catecholamines making them inactive
16
Q
pre-synaptic alpha 2 function
A
located on nerve terminals and inhibit release of norepi
17
Q
alpha 1 agonist effects
A
vasoconstriction, mydriasis, urinary retention, increased glycogenolysis
18
Q
alpha 1 antagonist effect
A
vasodilation, relaxed bladder
19
Q
alpha 2 agonist effects
A
decreased norepi release, decreased insulin release, CNS sedation
20
Q
alpha 2 antagonist effect
A
increased norepi release, increased insulin release, CNS excitation
21
Q
beta 1 agonist effect
A
increased HR, contractility, and renin release (increases BP)
22
Q
beta 1 antagonist effect
A
decreased HR, contractility, renin release (decreases BP)
23
Q
Beta 2 agonist effects
A
bronchodilation, vasodilation, increased glycogenolysis, uterine relaxation
24
Q
beta 3 agonist effects
A
lipolysis, bladder relaxation
25
beta 2 antagonist effects
bronchoconstriction, vasoconstriction, decreased glycogenolysis, uterine contraction
26
beta 3 antagonist effects
decreased lipolysis, bladder contraction
27
what is inotropy
force on contraction
28
what is chronotropy
rate at which heart beats
29
what is dromotropy
conduction velocity of electrical impulses
30
lusitropy
rate of relaxation of heart muscle after contraction
31
where is the baroreceptor reflex located
carotid sinus and aortic arch
32
what is epinephrine an agonist for
all adrenergic receptors
33
what receptors are more sensitive at high and low dose epi
low dose: beta receptors
high dose: alpha receptors
34
epinephrine effects of electrolytes
hypokalemia, high blood sugar
35
where is norepinephrine stored
postganglionic sympathetic nerve endings
36
dopamine effects on endocrine
suppresses pituitary hormones, depresses immune status, decreases secretion of growth hormone
37
dopamine effects on respiratory
interferes with ventilatory response to arterial hypoxemia/hypercapnia and depresses ventilation
38
is isoproterenol selective or nonselective beta agonist
nonselective, devoid of alpha in clinical doses
39
what does meperidine inhibit (weakly)
monoamine oxidase
40
infusion dose of phenylephrine
20-100mcg/min
41
what is the treatment for phenylephrine overdose
phentolamine
42
what is the preferred hypertension treatment for acute intoxication
nitro
43
what are examples of beta 2 agonists
albuterol, metaproterenol, terbutaline
44
what is the effect of ETT to administration of nebulizers
decreases 50-70%
45
what is a side effect of beta 2 agonists and when is it seen
tremors, usually seen when systemic absorption occurs (inhalers decrease this chance)
46
what is terbutaline used for
suppress labor
47
where does digoxin work
causes reversible inhibition of sodium-potassium pump in cardiac cells
48
electrolyte abnormalities that can contribute to digoxin toxicity
hypokalemia, hypomagnesemia, hypercalcemia
49
toxic level of digoxin
serum level greater than 3
50
symptoms of digoxin toxicity
anorexia, nausea, vomiting, atrial tach w/ block
51
digoxin toxicity treatment
digoxin antibodies
52
digoxin drug interactions
sympathomimetics and IV calcium: increase chance of dysrhythmia
diuretics/K+ loss: risk of toxicity
53
what does phosphodiesterase III do
hydrolyzes cAMP and cGMP
54
what does increased cAMP lead to
increased intracellular calcium increasing contractility and relaxing smooth muscle
55
what cardiac values are decreased by milrinone
LVEDP, MAP, CVP, PAOP, PVR, and SVR
56
what is lusitropic effect
enhanced relaxation of LV, beneficial in diastolic dysfunction
57
what does calcium do to contractility
increases
58
what were calcium sensitizers developed for and what is an example
cardiogenic shock, levosimendan
59
why are alpha antagonists not used in essential HTN
typically lead to tachycardia
60
what are alpha antagonists examples
phentolamine, prazosin, yohimbine, phenoxybenzamine
61
what alpha antagonist has irreversible binding
phenoxybenzamine
62
are phentolamine and phenoxybenzamine selective or nonselective
nonselective, post synaptic alpha 1 and presynaptic alpha 2
63
is prazosin selective
yes, selective alpha 1
64
is yohimbine selective
yes, alpha 2 selective
65
what does presynaptic alpha agonism lead to
inhibits release of norepi through negative feedback
66
what does presynaptic alpha blockade lead to
increases norepi release
67
what does postsynaptic alpha agonism lead to
vasoconstriction
68
what does postsynaptic alpha blockade lead to
inhibits normal responses to norepi
69
what is the action of phentolamine
nonselective alpha blockade leading to vasodilation and decrease in BP, the decrease in BP triggers baroreceptor to increase SNS activity
70
what surgery is phentolamine commonly used for
pheochromocytoma removal
71
what are clinical uses for phenoxybenzamine
preop BP control for pheo
chronic alpha blockade
expansion of intravascular fluid
raynaud's
72
what is the action and use of yohimbine
enhances release of norepi from nerve endings, used for idiopathic orthostatic hypotension and erectile dysfunction
73
what are examples of alpha antagonists used for BPH
doxazosin, prazosin, terazosin, tamsulosin, alfuzosin, sildosin
74
what is the effect of alpha 2 agonism
decrease norepinephrine release from presynaptic nerve terminals and reduce SNS outflow
75
where are most alpha 2 receptors
CNS (brainstem and locus cereuleus
76
What are the pharmacological effects of alpha 2 agonists
hypotension, bradycardia, central sedation, and some analgesic effects
77
what is alpha 2 to alpha 1 ratio for clonidine
400:1
78
what is alpha 2 to alpha 1 ratio for dexmedetomidine
1600:1
79
what is responsible for metabolism of dexmedetomidine
liver biotransformation, urine excretion
80
why are beta blockers continued during perioperative period
avoids risk of rebound SNS hyperactivity from abrupt discontinuation
81
what beta antagonist is the standard to which others are controlled
propranolol
82
what are nonselective beta blocker examples
propranolol, nadolol, timolol pindolol
83
what are cardioselective beta antagonists
metoprolol, atenolol, acebutalol, betazolol, esmolol, bisoprolol, nebivolol
84
what are 2 conditions worsened by beta 2 blockade
asthma, PVD
85
what are the effects of propranolol
decrease HR, increased PVR, increased myocardial oxygen requirements
86
what blood thinner decreases the protein binding of propranolol
heparin
87
what is unique about nadolol
long duration, given once per day, elimination half time 20-40 hours
88
what is the preferred beta blocker for glaucoma treatment
timolol, it decreases IOP
89
what is the most selective beta 1 antagonist
bisoprolol
90
what happens when excessive SNS activity is treated with beta blockers
fulminant pulmonary edema and irreversible cardiovascular collapse
91
what is responsible for metabolism of esmolol
rapid hydrolysis by plasma esterase
92
atropine dose for myocardial depression
7mcg/kg IV
93
glucagon dose for myocardial depression
1-10mg IV, 5mg/hr IV
94
preferred hypertension agent in pregnancy
labetalol
95
how long should be waited to start beta blockers after STEMI
at least 8 hours
96
what is ratio of beta to alpha for IV and PO labetalol
3:1 for oral, 7:1 for IV
97
what receptors does labetalol work on
selective alpha and nonselective beta
98
what are calcium channel blockers based on
chemical structure
99
what calcium channel blocker is a phenylalylamine
verapamil
100
what calcium channel blockers are dihydropyridines
clevidipine, nifedipine, nicardipine, nimodipine, isradipine, felodipine, amlodipine
101
what calcium channel blocker is a benzothiazepine
diltiazem
102
what is mechanism of action for calcium channel blockers
bind to voltage gated calcium ion channels maintaining them inactive reducing intracellular calcium movement
103
what specific site do calcium channel blockers bind to
alpha 1 subunit
104
what is the result of calcium channel blockers
decreased HR, reduced contractility, decreased conduction speed, smooth muscle relaxation
105
what are common uses for calcium channel blockers
artery spasm, increase coronary blood flow, chronic angina, negative inotropy
106
Verapamil is a synthetic derivative of what
papaverine
107
what type of calcium channel blockers may you see reflex tachycardia from baroreceptor mediation
dihydropyridines
108
preferred reason for using nifedipine
peripheral vasodilation and greater coronary coronary artery vasodilation
109
what happens when nifedipine is given to beta blocker use or preexisting LV failure
excessive myocardial depression
110
what calcium channel blocker has the greatest vasodilating effects
nicardipine
111
what calcium channel blocker is metabolized by plasma esterase
clevidipine, delayed with pseudocholinesterase activity
112
nimodopine use
subarachnoid hemorrhage, high specificity for cerebral arteries
113
what location does diltiazem work on
blocks calcium channels on AV node
114
what is the preferred drug for calcium channel overdose
dopamine
115
calcium channel blockers effect on neuromuscular blocking drugs
potentiate
116
calcium channel blockers effect on potassium supplements
may have higher levels than normal
117
calcium channel blockers effect on platelets
may interfere with platelet function, reduces prodrug conversion of plavix
118
