Autonomic Pharmacology Flashcards
(135 cards)
1
Q
what are 2 key roles of the autonomic nervous system
A
1) modulate contraction of smooth muscle
2) secretion from (endocrine and exocrine) glands
2
Q
where are the neural connections of the somatic vs the autonomic (PSNS and SNS) nervous systems
A
Somatic: in the CNS
Autonomic: in the PNS (PSNS - ganglia located close to the organ; SNS - ganglia located close to the spinal cord)
3
Q
in the autonomic nervous system, ganglia are located in (afferent/efferent) pathways
A
efferent
4
Q
the autonomic nervous system has (myelinated/unmyelinated) preganglionic neurons and (myelinated/unmyelinated) postganglionic neurons
A
myelinated; unmyelinated
5
Q
what are the 2 arms of the autonomic nervous system
A
PSNS and SNS
6
Q
what is the outflow of the sympathetic NS
A
thoracolumbar
7
Q
what is the outflow of the parasympathetic NS
A
craniosacral
8
Q
what is the ratio of pre to postganglionic neurons for the sympathetic ns? parasympathetic ns?
A
sympathetic: one pre to many post
parasympathetic: one pre to one post
9
Q
what is the distribution of RESPONSE and DISCHARGE for the sympathetic ns? parasympathetic ns?
A
sympathetic: generalized response, diffuse discharge
parasympathetic: limited response; discrete discharge
10
Q
T/F in general the SNS and PNS are physiological antagonists
A
T
11
Q
is the SNS or PNS essential for life
A
PNS
12
Q
what are 5 functions of the PNS:
1) pupillary ____________
2) _________ GI motility
3) __________ urination and defecation
4) __________ hr and bp
5) __________ absorption of nutrients
A
1) constriction
2) increased
3) increased
4) decreased
5) increased
13
Q
which branch of the autonomic nervous system is not essential for life
A
sympathetic nervous system
14
Q
what are the 6 functions of the SNS:
1) ________ heart rate and blood pressure
2) splenic ___________
3) ___________ of vessels in the skin
4) pupillary ____________
5) broncho___________
6) ________ blood glucose
A
1) increase
2) contraction
3) constriction
4) dilation
5) dilation
6) increase
15
Q
where are the sites of chemical transmission in the autonomic nervous system
A
1) between the pre and post-ganglionic neuron
2) between the post-ganglionic neuron and the target organ
16
Q
what are the 7 sites for pharmacological intervention in the PRESYNAPTIC neuron
A
1) action potential
2) synthesis of NT
3) storage of NT
4) metabolism of NT
5) release of NT
6) reuptake of NT
7) degradation of NT
17
Q
what are the 3 sites for pharmacological intervention in the POSTSYNAPTIC neuron
A
1) receptor binding
2) receptor stimulation (effectors)
3) response (secondary messengers)
18
Q
most drugs act via modifying actions on the pre or postsynaptic receptor
A
postsynaptic
19
Q
what does cholinergic neurons release
A
ACh
20
Q
all motor fibers in skeletal muscle use what type of NT at the neuromuscular junction
A
ACh
21
Q
what is the subdivision of cholinoreceptors
A
nicotinic (Nn and Nm) and muscarinic (M1-M5)
22
Q
what is the difference between nicotinic receptors Nn and Nm cholinoceptors in terms of the location
A
Nn: nicotinic neuronal - Autonomic ganglia (both sympathetic & parasympathetic), adrenal medulla
Nm: nicotinic motor end plate (neuromuscular junction)
23
Q
what does adrenergic neurons release
A
catecholamines (dopamine, E, NE)
24
Q
the adrenal medulla releases primarily _________, and some _________
A
epinephrine; norepinephrine
25
α1 and α2 adrenoceptors are involved in
contraction
26
describe the location of the following adrenoceptors:
β1:
β2:
β3:
β1 - heart
β2 - smooth muscle
β3 - fat
27
all preganglionic neurons release the NT ______, which binds to ______ receptors on the postganglionic neuron
ACh; nicotinic (Nn)
28
what effectors have muscarinic ACh receptors for the PARASYMPATHETIC NS
cardiac and smooth muscle; gland cells; nerve terminals
29
what effectors have muscarinic ACh receptors for the SYMPATHETIC and PARASYMPATHETIC NS
sweat glands
30
what effector organs respond to dopamine as a NT from the SYMPATHETIC NS
renal vascular smooth muscle
31
what effector organs have α and β adrenergic receptors for NE from the SYMPATHETIC NS
gland cells; cardiac and smooth muscle
32
Where is α1 located at
* Vascular smooth muscle
* iris
* bladder
33
What is the function of α1 receptor
* **Vasoconstriction**
* inc. BP
* pupil dilation (mydriasis)
* bladder sphincter contraction
34
Where is α2 located at
CNS (presynaptic), pancreas
35
What is the function of α2 receptor
* Inhibits norepinephrine release
* dec. insulin
* dec. sympathetic outflow (a feedback brake)
36
Where is β1 located
Heart, kidneys
37
What is the function of β1 receptor
* inc. HR
* inc. contractility
* inc. renin release
38
Where is β2 located at?
* **Bronchi**
* uterus
* vasculature (skeletal)
* GI
39
What is the function of β2 receptor?
* **Bronchodilation**
* vasodilation (skeletal muscle)
* dec. GI motility
* uterine relaxation
40
Where is β3 located at?
Adipose tissue, bladder
41
What is the function of β3 receptor?
* **Lipolysis**
* thermogenesis
* bladder detrusor relaxation (-> urine retention)
42
what type of ACh receptors exist at the gastrointestinal and genitourinary smooth muscle
M3
43
what type of ACh receptors exist at the bronchiolar SM
M3
44
what type of ACh receptors exist at the heart
M2
45
what type of ACh receptors exist at the salivary gland
M3
46
what type of ACh receptors exist at the eye
M3
47
what type of ACh receptors exist at the autonomic nerve endings
M2
48
what type of SNS receptors exist at the heart
β1
49
what type of SNS receptors exist on smooth muscle of the skin and splanchnic vessels
α1
50
what type of SNS receptors exist on smooth muscle of the skeletal muscle vessels
β2
51
what type of SNS receptors exist on splenic smooth muscle
α1
52
what type of SNS receptors exist at the bronchiolar SM
β2
53
what type of SNS receptors exist at the GI tract wall? GI tract sphincters
α2, β2; α1
54
what type of SNS receptors exist at the genitourinary tract SM of the:
1) bladder wall
2) sphincter
3) pregnant uterus
1) β2
2) α1
3) β2, α1
55
what type of SNS receptor exists at the penis and seminal vesicle smooth muscle
α1
56
what type of SNS receptor exists on salivary glands
α1
57
what type of SNS receptor exists on the eye muscles to cause:
1) contraction
2) relaxation
α1; β2
58
what type of SNS receptor exists at autonomic nerve endings
α2
59
adrenergic receptors alter
1) rate and force of contraction of the heart
2) tone of the blood vessels
60
what is the effect of α (alpha) receptors on vascular smooth muscle
contraction: increased TPR -> increased BP -> reflex decrease in heart rate
61
what is the effect of β receptors on vascular smooth muscle
relaxation: decreased TPR -> decreased BR -> increased heart rate
62
Which drugs are selective alpha agonist?
* phenylphrine (α1)
* xylazine (α2)
* dexmedetomidine/medetomidine/detomidine/romifidine (α2)
63
which drugs are nonselective β agonist?
isoproterenol (β1, β2)
64
which drugs are selective β agonist?
* dobutamine (β1)
* clenbuterol (β2)
* terbutaline (β2)
* Ractopamine (β1)
65
Which drugs are mixed α & β agonist?
* EPI (α1, α2, β1, β2)
* NE (α1, α2, β1, β3)
66
Epinephrine:
1) what type of agonist/antagonist
2) what receptors activated
1) mixed α/β agonist
2) activates all α and β subtypes
67
What are the cardiac effects of epinephrine and why
increases rate (chronotropy) and force (ionotropy) of contraction via β1
68
What are the vascular smooth muscle effects of epinephrine and why
mainly vasoconstriction -> increased TPR via α1
some vasodilation -> decreased TPR via β2
69
By activating α1 receptors, what are some other effects of epinephrine on other organs other than the heart
contraction of spleen, contraction of bladder sphincter, contraction of radial muscle of the iris causing mydriasis
70
By activating β2 receptors, what are some other effects of epinephrine
bronchodilation, decreased GI contractions, decreased uterine motility, relaxed bladder
71
How do drugs that stimulate α1 receptors cause the eyes to dilate
Contracting the radial muscle of the iris -> mydriasis
72
Clenbuterol:
1) what type of agonist/antagonist
2) what receptors activated
1) selective β agonist
2) β2
73
Terbutaline:
1) what type of agonist/antagonist
2) what receptors activated
1) selective β agonist
2) β2
74
Dobutamine:
1) what type of agonist/antagonist
2) what receptors activated
1) selective β agonist
2) β1
75
Phenylephrine:
1) what type of agonist/antagonist
2) what receptors activated
1) selective α agonist
2) α1
76
Isoproterenol:
1) what type of agonist/antagonist
2) what receptors activated
1) non-selective β agonist
2) β1/β2
77
What are the effects of clenbuterol/terbutaline and uses in the different species
bronchodilator
cats: asthma
dogs: chronic bronchitis
horses: lower airway disease
78
Ractopamine:
1) what type of agonist/antagonist
2) what receptors activated
1) selective β agonist
2) mainly β1, some β2
79
What is the therapeutic use of ractopamine and in what species
growth promotion in cattle; increases lean muscle deposition
80
What is the main therapeutic use of dobutamine and why
cardiac support (CHF) -> improves contracility and bp without significant tachycardia
81
what is a consequence of dobutamine overdose
ventricular tachycardia and hypertension
82
what is the main use of isoproterenol and what is a benefit with this drug particularly
stimulates heart (heart block or bradycardia); β2 stimulation also results in decreased TPR and decreased BP
83
what are the main therapeutic uses of phenylephrine
1) vasoconstriction and increased BP (with reflex drop in heart rate possible)
2) BP support
3) pupillary dilation
4) nasal decongestion (because of constriction)
84
what is unique about dopamine
dose-dependent effects
85
Dopamine receptor stimulation and effect:
1) low doses
2) moderate doses
3) high doses
1) D1: dilates renal vasculature -> increased GFR
2) β1: increases contractility
3) α1: vasoconstriction -> increases TPR -> increased BP
86
what are ephedrine, pseudoephedrine, and phenylpropanolamine
direct and indirect acting sympathomimetics -> activation of α and β and release of NE
87
what are the two main therapeutic uses of ephedrine and pseudoephedrine
1) decongestion
2) urinary tract incontinence
88
what is the main therapeutic use of phenylpropanolamine
urinary incontinence due to hypotonic urethra
89
what 2 adrenergic agonists can you give a patient with low BP or reduced blood flow (vascular hypotension) in the short-term
1) epinephrine
2) phenylephrine
90
what can you give a patient presenting with cardiac insufficiency (bradycardia, cardiogenic shock, CHF)
1) dopamine
2) dobutamine
3) epinephrine
4) isoproterenol
91
what can you use in combination to produce LOCAL vasoconstriction
epinephrine and lidocaine
92
what can you use to treat bronchoconstriction
1) clenbuterol (horse)
2) terbutaline (small animal)
3) epinephrine (respiratory issues associated with anaphylaxis)
93
what can you use to treat nasal congestion
1) phenylephrine
2) pseudoephedrine
3) ephedrine
94
what is the mainstay treatment of anaphylaxis (which causes both bronchospasm and cardiovascular collapse from vasodilation)
epinephrine
95
what can you use as a mydriatic to facilitate retinal examination
phenylephrine
96
what is a nonselective α antagonists?
phenoxybenzamine (α1, α2)
97
What are some selective α antagonist?
* prazosin (α1)
* yohimbine (α2)
* atipemazole (α2)
98
what is a nonselective β antagonist?
* propranolol (β1, β2)
99
What is a selective β antagonist?
* atenolol (β1)
* metoprolol (β2)
100
what is a mixed adrenergic antagonists? (β ≥ α1)
Carvedilol
101
phenoxybenzamine:
1) what type of agonist/antagonist
2) what receptors activated
1) non-selective α-antagonist
2) α1, a2
102
prazosin:
1) what type of agonist/antagonist
2) what receptors activated
1) selective α-antagonist
2) α1
103
atenolol:
1) what type of agonist/antagonist
2) what receptors activated
1) selective β-antagonist
2) β1
104
metoprolol:
1) what type of agonist/antagonist
2) what receptors activated
1) selective β antagonist
2) β1
105
proponalol:
1) what type of agonist/antagonist
2) what receptors activated
1) nonselective β antagonist
2) β1, β2
106
carvedilol:
1) what type of agonist/antagonist
2) what receptors activated
1) mixed adrenergic antagonist
2) β > α1
107
what are the therapeutic uses of phenoxybenzamine
1) diagnosis and treatment of pheochromocytoma
2) hypertonic urethra
108
what is a major adverse effect of phenoxybenzamine and an important therapeutic consideration
can cause severe hypotension (blocking α1) -> do not want to give epinephrine to reverse because the α receptors are blocked, so only the β effects of epinephrine will remain -> can get even further hypotension
109
what are the therapeutic uses of prazosin
hypertonic urethra due to functional obstruction; can be used to help treat CHF
110
in regards to β antagonists, drugs with higher affinity for what receptor are more useful clinically
β1
111
β antagonists are used for what 2 diseases
1) cardiovascular
2) ocular
112
what is the therapeutic use of propanolol
supraventricular and ventricular tachyarrhythmias, thyrotoxicosis for cats with hyperthyroidism, pheochromocytoma, HCM in cats
113
what β antagonist has minimal hepatic first pass effects
atenolol
114
what are the therapeutic uses of atenolol and metoprolol
same as propanolol BUT they have reduced adverse effects like bronchospasm
115
what are the therapeutic usees of carvedilol
cardiomyopathy in dogs, free-radical scavenger
116
bethanechol:
1) what type of agonist/antagonist
2) what receptors activated
1) cholinergic agonist
2) muscarinic
117
what is the therapeutic use of bethanechol
stimulates urinary bladder -> hypocontractile bladder
118
when is bethanechol contraindicated
GI or urinary obstruction
119
what is a possible side effect of bethanechol and what is the antidote
salivation, lacrimation, urination, defacation; atropine (muscarinic blocker)
120
what are the therapeutic uses of pilocarpine
pupillary constriction (miosis) and tear production
121
what is the mechanism of action of edrophonium and what are 2 key factors about it
prolongs half life of ACh by binding to the active site of acetylcholinesterase; short duration of action and poor penetration into the CNS
122
what is the mechanism of action of neostigmine/pyridostigmine and what are 2 key factors
carbamylates active site of acetylcholinesterase; longer duration of action than edrophonium and poor penetration into CNS
123
what are the therapeutic uses of edrophonium/neostigmine/pyridostigmine
intestinal motility disorders (ex. paralytic ileus)
124
what are the 2 classes of non-selective muscarinic cholinergic antagonists
tertiary amides, quaternary ammonium compounds
125
what cholinergic antagonists are tertiary amides
atropine, oxybutynin tropicamide
126
what cholinergic antagonists are quaternary ammonium compounds
propantheline, ipratropium, hyoscine
127
what are the therapeutic uses of atropine
mydriasis (pupil dilation) and reduced ciliary spasms (uveitis), treating organophosphate poisoning, bradyarrhythmias
128
what are the therapeutic uses of tropicamide
pupil dilation (mydriasis)
129
what are some possible adverse effects of oxybutynin
constipation and urine retention
130
what are the therapeutic uses of oxybutynin and what is a general caution
spastic bladder; do not use if bladder or GI obstruction or if there is an infection
131
do tertiary amines or quaternary ammoniums have more CNS effects
tertiary amines
132
what are the therapeutic uses of propantheline
GI motility disorders, spastic bladder
133
what are the therapeutic uses of ipratropium
bronchospasm associated with respiratory disorders
134
what are the therapeutic uses of hyoscine and what is a potential adverse effect
GI motility disorders; can cause tachycardia and reduced GI motility
135
what is a potential use of hyoscine
acute severe exacerbations of airway obstruction in horses -> it causes immediate bronchodilation
