Sympathetic neurotransmission and adrenoceptor agonists and antagonists Flashcards
Despite its ability to stimulate receptors in the sympathetic nervous system, norepinephrine has relatively little capacity to increase bronchial airflow because the receptors in bronchial smooth muscle are largely of the
A
β2 subtype.
B
α1 subtype.
C
D2 subtype.
D
5-HT4 subtype.
E
M3 subtype.
A
β2 subtype.
A 38-year-old man is taking tranylcypromine, an MAO inhibitor, for depression. After a celebratory dinner, he develops a severe headache and chest pain. At hospital his blood pressure is 190/135 mm Hg. His hypertensive crisis is likely due to the ingestion of
A
green salad.
B
chocolate cake.
C
red wine.
D
broiled salmon.
E
wheat bread.
C
red wine.
A 53-year-old woman with COPD is using an albuterol inhaler for symptomatic relief of bronchospasm. She does not like using her inhaler because it causes
A
her lips to turn black.
B
her heart to beat faster.
C
numbness in her fingers and toes.
D
transient blindness.
E
transient diminished hearing.
B
her heart to beat faster.
A 23-year-old male college student is taking amphetamine on a regular basis to stay alert while studying. The mechanism of action of amphetamine that causes this effect is
A
due to the release of epinephrine (E) from the adrenal medulla.
B
due to the release of histamine from mast cells.
C
due to the stimulation of β receptors in the frontal cortex of the brain.
D
due to the release of norepinephrine (NE) from central adrenergic neurons.
E
the result of inhibition of monoamine oxidase (MAO).
D
due to the release of norepinephrine (NE) from central adrenergic neurons.
A 34-year-old woman has been frequently using a nasal spray containing the α adrenergic receptor agonist oxymetazoline for nasal decongestion. She has recently noticed that it is less effective and her symptoms are worse. This loss of efficacy is most likely due to
A
the fact that her spray container is empty.
B
degradation of the oxymetazoline.
C
a manufacturing defect in the nasal spray container.
D
a loss of innervation to her nasal mucosa.
E
rebound hyperemia of her nasal mucosa.
E
rebound hyperemia of her nasal mucosa.
A 32-year-old woman with the diagnosis of a pheochromocytoma is scheduled for surgery to remove her adrenal tumor. The best drug to control her episodes of severe hypertension prior to surgery would be
A
a nonselective α adrenergic antagonist such as phenoxybenzamine.
B
a selective α2 adrenergic receptor agonist such as clonidine.
C
a selective β2 adrenergic receptor agonist such as terbutaline.
D
a nonselective β adrenergic receptor antagonist such as propranolol.
E
a selective α1 adrenergic receptor antagonist such as terazosin.
A
a nonselective α adrenergic antagonist such as phenoxybenzamine.
The typical dose of oral propranolol for the treatment of hypertension is 320 mg/day. The typical dose of IV propranolol to treat a life-threatening arrhythmia is 1 to 3 mg administered slowly. The reason for the discrepancy in these doses is
A
β adrenergic receptors are more sensitive to IV than oral propranolol.
B
the IV dose avoids the “first pass” metabolism of oral propranolol.
C
treatment of hypertension requires a higher dose of propranolol than does treatment of a cardiac arrhythmia.
D
the density of β2 receptors in the heart is greater than the density of β2 receptors on blood vessels.
E
oral propranolol is excreted by the kidney at a faster rate than IV propranolol.
B
the IV dose avoids the “first pass” metabolism of oral propranolol.
A 32-year-old woman is taking sertraline for mild depression. This drug increases the availability of serotonin (5-HT) at the postsynaptic membrane because it
A
stimulates 5-HT4 receptors.
B
enhances the release of 5-HT from presynaptic nerve endings.
C
inhibits the presynaptic uptake of 5-HT.
D
blocks MAO which degrades 5-HT.
E
enhances the synthesis of 5-HT.
C
inhibits the presynaptic uptake of 5-HT.
A 35-year-old man is taking buspirone for anxiety. This drug acts as a(n)
A
partial agonist at 5-HT1A receptors.
B
inhibitor of 5-HT reuptake into presynaptic nerve terminals.
C
agonist at dopamine receptors.
D
agonist at α2 adrenergic receptors.
E
antagonist at M3 receptors.
A
partial agonist at 5-HT1A receptors.
A major mechanism for the termination of dopamine’s (DA) postsynaptic effect is
A
downregulation of DA postsynaptic receptors.
B
degradation of DA in postsynaptic nerve terminals.
C
decreased synthesis of DA.
D
blockage of postsynaptic β adrenergic receptors.
E
reuptake of DA into presynaptic nerve terminals.
E
reuptake of DA into presynaptic nerve terminals.
A 42-year-old man has just been prescribed a new drug. After several doses he notices dry mouth, dry eyes, and a rapid heart rate. This is most likely due to an inhibition of which of the following neurotransmitter:
A
Norepinephrine
B
Serotonin
C
Glutamate
D
Acetylcholine
E
Epinephrine
D
Acetylcholine
A 23-year-old man is accosted by 3 men late at night. Immediately his heart rate increases due to an increase in epinephrine in his circulation. This release of epinephrine from the adrenal medulla is the result of the action of acetylcholine on
A
muscarinic receptors.
B
α adrenergic receptors.
C
nicotinic receptors.
D
β adrenergic receptors.
E
glutamate receptors.
C
nicotinic receptors.
56-year-old woman goes to an ophthalmologist for an eye examination. The ophthalmologist administers an eye drop to dilate her pupils prior to the eye examination. The medication in the eye drop is most likely acting on
A
serotonin receptors.
B
α1 adrenergic receptors.
C
β2 adrenergic receptors.
D
nicotinic receptors.
E
acetylcholinesterase.
B
α1 adrenergic receptors.
The neurotransmitter at the neuromuscular junction is
A
acetylcholine.
B
norepinephrine.
C
serotonin.
D
aspartate.
E
epinephrine.
A
acetylcholine.
A 33-year-old woman with a brain infection (meningitis) is administered her antibiotic directly into the cerebrospinal fluid because the
A
bacteria causing the brain infection are not sensitive to the antibiotic.
B
blood brain barrier excludes the antibiotic if it is administered systemically.
C
antibiotic binds to brain cells and is not available to the bacteria.
D
antibiotic is activated by the cerebrospinal fluid.
E
bacteria are mostly located in the cerebrospinal fluid.
B
blood brain barrier excludes the antibiotic if it is administered systemically.
An 80-year-old woman is administered a CNS depressant drug for anxiety. When she abruptly stops the drug, after taking it for many years, she is likely to experience
A
increased sedation.
B
hyperexcitability.
C
a depressed mood.
D
nausea.
E
blurred vision.
B
hyperexcitability.
A 35-year-old man has ingested Amanita muscaria mushrooms. He is experiencing a heart rate of 40 beats per minute. This bradycardia is most likely due to an interaction of the chemical(s) in the mushrooms with which receptors at the sinoatrial node?
A
α1 Adrenergic
B
β1 Adrenergic
C
β2 Adrenergic
D
M2 muscarinic
E
Nicotinic
D
M2 muscarinic
A 49-year-old woman is treated with pilocarpine hydrochloride for xerostomia (dry mouth) following head and neck radiation treatments. As a result of taking this drug she may experience which of the following side effects?
A
Sweating
B
Dry eyes
C
Dry skin
D
Confusion
E
Tachycardia
A
Sweating
A 54-year-old woman is receiving Botox injections to remove facial wrinkles. Botox (botulinum toxin) acts by
A
stimulating the release of ACh.
B
stimulating the release of norepinephrine.
C
blocking the release of ACh.
D
blocking the release of norepinephrine.
E
blocking muscarinic receptors.
C
blocking the release of ACh.
A 23-year-old man has deliberately ingested an organophosphate insecticide. His initial symptoms of salivation, lacrimation, and diarrhea are a consequence of inhibition of
A
butyrylcholinesterase.
B
acetylcholinesterase.
C
Na+, K+-ATPase.
D
tyrosine hydroxylase.
E
monoamine oxidase.
B
acetylcholinesterase.
A 23-year-old man has deliberately ingested an organophosphate insecticide. He has initial symptoms of salivation, lacrimation, and diarrhea….This patient should be treated with atropine and which additional drug in the following list?
A
Physostigmine
B
Bethanechol
C
Pralidoxime
D
Morphine
E
Gentamicin
C
Pralidoxime
A 65-year-old man with the diagnosis of Alzheimer’s disease is being treated with donepezil. This drug acts by
A
stimulating the release of ACh.
B
blocking the reuptake of norepinephrine.
C
inhibiting monamine oxidase.
D
blocking the release of ACh.
E
inhibiting AChE.
E
inhibiting AChE
A 53-year-old man is scheduled to receive vecuronium as an adjuvant muscle relaxant during abdominal surgery. The dose of vecuronium may have to be adjusted if this patient is also receiving
A
gentamicin.
B
penicillin.
C
ibuprofen.
D
acetaminophen.
E
prednisone.
A
gentamicin
A 72-year-old woman receives succinylcholine as an adjuvant muscle relaxant during knee surgery. This drug acts by
A
blocking ACh at nicotinic receptors of neuromuscular endplate.
B
blocking ACh at nicotinic receptors in the adrenal medulla.
C
increasing Na+ and K+ permeability of the postsynaptic neuromuscular membrane.
D
blocking the transmission of the action potential along the nerve axon.
E
blocking the release of ACh from neuromuscular presynaptic vesicles.
C
increasing Na+ and K+ permeability of the postsynaptic neuromuscular membrane.
