Pharma - Autonomic Drugs (Part 1) Flashcards
1
Q
From which regions of the central nervous system do parasympathetic nerves originate?
A
Cranial and sacral regions
2
Q
From which regions of the central nervous system do sympathetic nerves originate?
A
Thoracic and lumbar regions
3
Q
What types of nerves arise from the spinal cord and innervate skeletal muscle directly?
A
Somatic nerves
4
Q
How many neurons are involved in parasympathetic transmission from the spinal cord to the target organ?
A
Two
5
Q
True or False? Craniosacral parasympathetic axons synapse on neurons in the peripheral ganglia.
A
TRUE
6
Q
What neurotransmitter mediates parasympathetic nervous system function?
A
Acetylcholine
7
Q
What neurotransmitter receptor mediates parasympathetic nervous system function at the peripheral ganglia?
A
Nicotinic acetylcholine receptors
8
Q
What neurotransmitter receptor mediates parasympathetic tone in the cardiac muscle?
A
Muscarinic acetylcholine receptors (specifically, M2)
9
Q
What neurotransmitter receptor mediates parasympathetic tone in the smooth muscle?
A
Muscarinic acetylcholine receptors (specifically, M3)
10
Q
What neurotransmitter receptor mediates parasympathetic tone in the glandular cells?
A
Muscarinic acetylcholine receptors (specifically, M1 and M3)
11
Q
Somatic nerves that arise from the spine innervate skeletal muscle. What neurotransmitter receptor, which is located on skeletal muscle, receives this input?
A
Nicotinic acetylcholine receptors
12
Q
How many neurons are involved in sympathetic transmission from the spinal cord to the target organ?
A
Two
13
Q
Where is the first synapse after the spinal cord in sympathetic innervation of an organ?
A
Preganglionic sympathetic axons synapse on neurons in the paravertebral ganglia
14
Q
True or False? Preganglionic sympathetic axons synapse on neurons in the peripheral ganglia.
A
FALSE
preganglionic sympathetic axons synapse on neurons in the paravertebral ganglia
15
Q
At the paravertebral ganglia, the neurotransmitter _____ acts on _____ receptors to mediate sympathetic nervous system function.
A
Acetylcholine; nicotinic acetylcholine
16
Q
What neurotransmitter mediates sympathetic nervous system function at the sweat glands?
A
Acetylcholine
17
Q
What neurotransmitter receptor mediates sympathetic nervous system function at the sweat glands?
A
Muscarinic acetylcholine receptors
18
Q
What neurotransmitter mediates sympathetic tone in the cardiac muscle, smooth muscle, and glandular cells?
A
Norepinephrine
19
Q
What are four cell types in which α- and β-adrenergic receptors mediate sympathetic tone?
A
Cardiac muscle, smooth muscle, glandular cells, and terminal ends of neurons
20
Q
What neurotransmitter mediates sympathetic tone in the renal vascular smooth muscle?
A
Dopamine
21
Q
What neurotransmitter receptor mediates sympathetic tone in the renal vascular smooth muscle?
A
D1 receptors
22
Q
What two substances are released into the blood from the adrenal medulla after the activation of the sympathetic nervous system?
A
Epinephrine and norepinephrine
23
Q
How many synapses are involved in activation of the adrenal medulla?
A
One
the adrenal medulla releases epinephrine and norepinephrine into the blood
24
Q
Are nicotinic acetylcholine receptors ligand-gated sodium-potassium channels or G-protein coupled receptors?
A
Nicotinic receptors are ligand gated sodium-potassium channels
25
Are muscarinic acetylcholine receptors ligand-gated sodium-potassium channels or G-protein-coupled receptors?
Muscarinic acetylcholine receptors are G-protein-coupled receptors that act through second messengers
26
To what class of G-proteins are α1-receptors linked?
q
27
To what class of G-proteins are α2-receptors linked?
i
28
To what class of G-proteins are β1-receptors linked?
s
29
To what class of G-proteins are β2-receptors linked?
s
30
To what class of G-proteins are M1-receptors linked?
q
31
To what class of G-proteins are M2-receptors linked?
i
32
To what class of G-proteins are M3-receptors linked?
q
33
To what class of G-proteins are D1-receptors linked?
s
34
To what class of G-proteins are D2-receptors linked?
i
35
To what class of G-proteins are H1-receptors linked?
q
36
To what class of G-proteins are H2-receptors linked?
s
37
To what class of G-proteins are V1-receptors linked?
q
38
To what class of G-proteins are V2-receptors linked?
s
39
What are the major effects of α1-receptor activation?
It increases vascular smooth muscle contraction, and increases pupillary dilator muscle contraction (mydriasis)
40
What are the major functions of α2-receptor activation?
It decreases sympathetic outflow and decreases insulin release
41
What are the major functions of β1-receptor activation?
It increases heart rate and contractility, increases renin release from the kidneys, and increases lipolysis of adipose tissue
42
What is the major function of β2-receptor activation on the body's vasculature?
Vasodilation
43
What is the major function of β2-receptor activation on the respiratory system?
Bronchodilation
44
What effect does β2-receptor activation have on glucagon release?
It increases glucagon release
45
Where are M1-receptors located?
The central nervous system
46
What effect does M2-receptor activation have on cardiac function?
It decreases heart rate and contractility
47
What are the effects of M3-receptor activation?
Increased exocrine gland secretions, gut peristalsis, bladder contraction, bronchoconstriction, miosis, and accommodation
48
What effect does D1-receptor activation have on renal vasculature?
It relaxes renal vascular smooth muscle
49
What are the effects of H1-receptor activation?
Pruritis, pain, nasal and bronchial mucus production, contraction of bronchioles
50
What is the effect of H2-receptor activation?
It increases gastric acid secretion
51
What effect does V1-receptor activation have on vascular smooth muscle?
It increases vascular smooth muscle contraction
52
The activation of what two types of G-protein-coupled receptors can increase vascular smooth muscle contraction? Which receptors mediate vascular relaxation?
α1- and V1-receptors increase contraction; relaxation is mediated by β2, and D1 (renal only)
53
What is the effect of V2-receptor activation? Where are they located?
It increases water permeability and reabsorption in the collecting tubules of the kidney
54
What five types of receptors are coupled with Gq proteins?
α1, M1, M3, H1, and V1
55
What five types of receptors are coupled with Gs proteins?
β1, β2, D1, H2, and V2
56
What three types of receptors are coupled with Gi proteins?
a2, M2, and D2
57
What enzyme is activated directly downstream of Gq-coupled receptors?
Phospholipase C
58
What enzyme is activated directly downstream of Gs-coupled receptors?
Adenyl cyclase
59
What enzyme is inhibited directly downstream of Gi-coupled receptors?
Adenyl cyclase
60
Adenyl cyclase catalyzes the conversion of adenosine triphosphate into what molecule?
cAMP
61
What final effector enzyme is activated by receptors that are coupled with Gs proteins?
Protein kinase A
62
What final effector enzyme is inhibited by receptors that are coupled with Gi proteins?
Protein kinase A
63
Phospholipase C catalyzes the cleavage of membrane lipids into what molecules?
Inositol trisphosphate3 and diacylglycerol
64
What is the effect of increased inositol triphosphate on the intracellular concentration of calcium?
It increases the intracellular calcium concentration
65
What enzyme is activated by diacylglycerol?
Protein kinase C
66
What pharmacologic agent blocks the uptake of choline into cholinergic nerve terminals?
Hemicholinium
67
What enzyme is responsible for the formation of acetylcholine? What are its two substrates?
Choline acetyltransferase; Acetyl-CoA and choline
68
What pharmacologic agent blocks the transport of acetylcholine into the presynaptic vesicles in nerve terminals?
Vesamicol
69
The entry of what ion into the nerve terminal induces the release of acetylcholine into the synaptic cleft?
Calcium
70
What toxin inhibits the calcium-induced release of acetylcholine from the cholinergic nerve terminals?
Botulinum
71
What enzyme breaks down acetylcholine in the synaptic cleft? What two products result from this reaction?
Acetylcholinesterase; choline and acetate
72
Tyrosine transporters are located in the nerve terminals of what type of cells?
Noradrenergic cells; tyrosine is the precursor of norepinephrine
73
Tyrosine is a precursor to the formation of which neurotransmitters? What is the order of their synthesis?
Tyrosine, DOPA, dopamine, norepinephrine, epinephrine
74
What pharmacologic agent blocks the conversion of tyrosine to DOPA?
Metyrosine
75
Tyrosine is converted into dopamine via what intermediate precursor?
DOPA; DOPA can be used as a pharmacologic agent to increase central nervous system dopamine
76
What pharmacologic agent blocks the transport of dopamine into the presynaptic vesicles in nerve terminals?
Reserpine
77
Dopamine is converted into norepinephrine in the ______ (cytoplasm/presynaptic vesicle).
Presynaptic vesicles
78
The entry of what ion into the nerve terminal induces the release of norepinephrine into the synaptic cleft?
Calcium
79
What pharmacologic agent inhibits the calcium-induced release of norepinephrine from the noradrenergic nerve terminals?
Guanethidine
80
What pharmacologic agent stimulates the release of norepinephrine from the noradrenergic nerve terminals?
Amphetamine
81
How is norepinephrine cleared form the synaptic cleft?
Diffusion, metabolism (monoamine oxidase A), and reuptake
82
What pharmacologic agents inhibit the reuptake of norepinephrine into the nerve terminals?
Cocaine, amphetamine, and tricyclic antidepressants
83
What three receptor types modulate the presynaptic release of norepinephrine from the noradrenergic nerve terminals?
M2-receptors, angiotensin II receptors, and α2-receptors
84
What effect does the activation of α2-receptors in presynaptic sympathetic nerve terminals have on norepinephrine release?
It inhibits norepinephrine release
85
What effect does the activation of angiotensin II receptors in presynaptic sympathetic nerve terminals have on norepinephrine release?
It stimulates norepinephrine release
86
What effect does the activation of M2-receptors in presynaptic sympathetic nerve terminals have on norepinephrine release?
It inhibits norepinephrine release
87
The norepinephrine-mediated activation of α2-receptors on presynaptic sympathetic nerve terminals is an example of a mechanism of what type of feedback?
Negative feedback
88
Name four direct cholinergic agonists.
Bethanechol, carbachol, pilocarpine, methacholine
89
What is the clinical application of bethanechol?
Treatment of postoperative and neurogenic ileus and urinary retention (remember: **Beth Anne, call (bethanechol)** me if you want to activate your **Bowels** and **Bladder**)
90
What is the mechanism of action of bethanechol?
Bethanechol is a direct cholinergic agonist resistant to acetylcholinesterase that works on receptors in the bowel and bladder
91
What two direct agonist cholinomimetic drugs can be used to treat glaucoma?
Carbachol and pilocarpine
92
Carbachol and pilocarpine are effective for the treatment of open-angle glaucoma because they activate what muscle?
The ciliary muscle of the eye
93
What is a methacholine challenge test?
A test in which methacholine is inhaled to stimulate muscarinic receptors and induce bronchoconstriction to diagnose asthma
94
Pilocarpine is effective for the treatment of narrow-angle glaucoma because it activates what muscle?
The pupillary sphincter
95
True or False? Pilocarpine is susceptible to acetylcholinesterase.
FALSE
## Footnote
pilocarpine is resistant to acetylcholinesterase
96
Name five indirect cholinergic agonists.
Neostigmine, pyridostigmine, edrophonium, physostigmine, echothiophate
97
What are the clinical indications for use of neostigmine?
The treatment of postoperative and neurogenic ileus
98
True or False? The treatment of myasthenia gravis is a clinical application of pyridostigmine.
TRUE
99
Which anticholinesterase is used to diagnose myasthenia gravis? Why?
Edrophonium; the effects last for minutes and if weakness is transiently reversed it is diagnostic of myasthenia gravis
100
True or False? The treatment of glaucoma is a clinical application of physostigmine.
TRUE
## Footnote
(remember: "PHYS is for the EYES")
101
Which pharmacologic agent is used to treat atropine overdose?
Physostigmine, because it crosses the blood-brain barrier and is able to reverse central nervous system as well as peripheral nervous system effects
102
What is the clinical indication for use of echothiophate?
The treatment of glaucoma
103
Indirect cholinergic agonists increase endogenous acetylcholine by inhibiting what enzyme?
Acetylcholinesterase
104
Why is pyridostigmine used to treat myasthenia gravis?
It increases the amount of acetylcholine in the neuromuscular synapse, thereby increasing muscle strength
105
What effect does neostigmine have on the central nervous system?
None; it does not penetrate the blood-brain barrier (remember: NEO CNS = NO CNS)
106
What is the clinical application and mechanism of action of topical atropine, homatropine, and tropicamide?
These drugs antagonize muscarinic receptors in the eye to produce mydriasis and cycloplegia
107
What is the mechanism and clinical application for benztropine?
It is a muscarinic antagonist used to reduce symptoms of Parkinson's disease
108
What is the mechanism and clinical application for scopolamine?
It is a muscarinic antagonist used to treat motion sickness
109
What is the mechanism and clinical application for ipratropium?
It is a muscarinic antagonist used to treat asthma and chronic obstructive pulmonary disease (remember: **I PRAY** I can breathe soon!)
110
What is the mechanism and clinical application for methscopolamine?
It is a muscarinic antagonist used to treat peptic ulcers
111
What is the mechanism and clinical application for oxybutynin?
It is a muscarinic antagonist used to reduce urgency in mild cystitis and reduce bladder spasms
112
What is the mechanism and clinical application for glycopyrrolate?
It is a muscarinic antagonist used to reduce urgency in mild cystitis and reduce bladder spasms
113
What is the mechanism and clinical application for pirenzepine?
It is a muscarinic antagonist used to treat peptic ulcers
114
What is the mechanism and clinical application for propantheline?
It is a muscarinic antagonist used to treat peptic ulcers
115
Which muscarinic antagonist can be used to reduce urgency in patients with mild cystitis?
Oxybutynin (also glycopyrrolate)
116
Which muscarinic antagonist is most commonly used to treat motion sickness?
Scopolamine
117
Which muscarinic antagonist can be used to treat bladder spasms?
Oxybutynin (also glycopyrrolate)
118
You recently prescribed haloperidol to your patient to treat his schizophrenia, but he has since developed Parkinson's-like motor adverse effects. What drug could you add to his regimen to treat this?
Benztropine
119
Atropine is used for therapeutic effect in which four organ systems?
Eyes, gastrointestinal system, respiratory system, urinary system
120
What are the two effects of atropine on the eye?
Pupil dilation, cycloplegia
121
What is the effect of atropine on the airway mucosa?
It decreases secretions
122
What is the effect of atropine on the stomach?
It decreases acid secretion
123
What is the effect of atropine on gastrointestinal motility?
It decreases motility
124
What is the effect of atropine on the bladder in a patient with cystitis?
It decreases urgency
125
(A) represents what neurotransmitter and receptor type?
Acetylcholine neurotransmitter; nicotinic receptor
126
Part of the sympathetic NS, sweat glands and adrenal medulla are innervated by which neurotransmitter/receptor group, marked (A) and (B)?
(A) acetylcholine neurotransmitter/muscarinic receptor; (B) nicotinic neurotransmitter/muscarinic receptor
127
A patient affected by botulinum toxin will be affected at which neurotransmitter/receptor group(s)?
Botulinum toxin affects all neurotransmitter/receptor groups that have acetylcholine as the neurotransmitter
