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.
A 3-year-old boy is brought to the emergency room because he has ingested a large amount of a nicotine-containing product. Serious nicotine toxicity in this child is the result of
A
blockade of transmission at autonomic ganglia and neuromuscular junctions.
B
blockade of muscarinic receptors.
C
stimulation of adrenergic receptors.
D
blockade of adrenergic receptors.
E
stimulation of muscarinic receptors.
A
blockade of transmission at autonomic ganglia and neuromuscular junctions.
A 72-year-old man with Parkinson’s disease is being treated with selegiline. Over the past 2 weeks he has noticed an increase in insomnia and anxiety. It is likely these symptoms are due to
A
dopamine.
B
ephedrine.
C
amphetamine.
D
serotonin.
E
caffeine.
C
amphetamine.
A 75-year-old woman with Parkinson’s disease is being treated with the combination of levodopa/carbidopa. Entacapone is added. This patient is treated with this combination of drugs to increase the amount of which of the following substance to reach the CNS?
A
Carbidopa
B
Levodopa
C
Entacapone
D
Acetylcholine
E
Dopamine
B
Levodopa
A 66-year-old woman with Alzheimer’s disease is being treated with the cholinesterase inhibitor donepezil. The patient’s family learns that donepezil is related to pesticides. When the family expresses concern they are told that donepezil may decrease the rate of cognition decline by increasing the concentration of which substance in the brain?
A
Acetylcholine
B
Serotonin
C
Dopamine
D
Epinephrine
E
Glutamate
A
Acetylcholine
A 73-year-old man with Alzheimer’s disease is being treated with donepezil. Because his cognition is deteriorating, memantine is added. Memantine is a noncompetitive antagonist of the
A
dopamine D2 receptor.
B
NMDA-type glutamate receptor.
C
β adrenergic receptor.
D
α adrenergic receptor.
E
5-HT2 serotonergic receptor.
B
NMDA-type glutamate receptor.
A 57-year-old man with amyotrophic lateral sclerosis is treated with riluzole. The patient’s family is told that the drug may extend survival by
A
2 to 3 days.
B
2 to 3 months.
C
2 to 3 years.
D
an indefinite period of time.
E
none of the above; because it is not thought to extend survival.
B
2 to 3 months.
A 65-year-old man with Parkinson’s disease is treated with pramipexole. This drug acts as an agonist at striatal
A
5-HT serotonergic receptors.
B
D1 dopaminergic receptors.
C
norepinephrine adrenergic receptors.
D
D2 dopaminergic receptors.
E
opiate μ receptors.
D
D2 dopaminergic receptors.
A woman with facial muscle spasms is treated with an
agent that inhibits the release of acetylcholine. Which
side effect is most likely to occur in this patient?
(A) bradycardia
(B) urinary incontinence
(C) dry mouth
(D) diarrhea
(E) constriction of the pupils
(C) dry mouth
A man complains of dry mouth after radiation therapy
for throat cancer, and he is treated with cevimeline.
Which mechanism produces the therapeutic effect of
this drug?
(A) activation of muscarinic M2 receptors
(B) increased formation of IP3
(C) increased cAMP levels
(D) increased cGMP levels
(E) increased potassium efflux
(B) increased formation of IP3
A woman in a smoking cessation program receives a
drug that reduces craving and withdrawal effects.
Which effect results from receptor activation by this
drug?
(A) sodium influx
(B) potassium efflux
(C) increased cAMP
(D) increased cGMP
(E) IP3 formation
(A) sodium influx
A man receives a drug that increases cGMP levels.
Which adverse effect is most likely to result from this
medication?
(A) constipation
(B) cough
(C) dry mouth
(D) sedation
(E) headache
(E) headache
An agricultural worker is brought to the emergency
department after abrupt onset of bowel and bladder
incontinence and muscle weakness while she was
working. She is given oxygen and antidotal drug
treatments. Which drug mechanism would increase
muscle strength in this patient?
(A) blockade of muscarinic receptors
(B) activation of nicotinic receptors
(C) increased neurotransmitter degradation
(D) induction of drug-metabolizing enzymes
(E) increased urinary excretion of weak acids
(C) increased neurotransmitter degradation
Which drug produces transient muscle fasciculations
followed by muscle paralysis that is not reversed by
neostigmine?
(A) rocuronium
(B) hyoscyamine
(C) cisatracurium
(D) succinylcholine
(E) pancuronium
(D) succinylcholine
Toxic doses of scopolamine would be expected to cause
all of the following effects EXCEPT
(A) hallucinations.
(B) bronchospasm.
(C) hyperthermia.
(D) urinary retention.
(E) blurred vision.
(B) bronchospasm.
Topical ocular administration of tropicamide will cause
(A) contraction of the ciliary muscle.
(B) vasoconstriction.
(C) miosis.
(D) relaxation of the iris sphincter muscle.
(E) lacrimation.
(D) relaxation of the iris sphincter muscle.
The therapeutic use of darifenacin is based on its
ability to
(A) relax bronchial smooth muscle.
(B) relax urinary bladder smooth muscle.
(C) relax uterine smooth muscle.
(D) inhibit salivary secretions.
(E) relax gastrointestinal muscle.
(B) relax urinary bladder smooth muscle.
Sugammadex, used to reverse an overdose with
neuromuscular blockers, has a unique mechanism of
action best described as which one of the following?
(A) agonist at cholinergic acetylcholine receptors
(B) antagonist at cholinergic acetylcholine receptors
(C) antagonist at muscarinic acetylcholine receptors
(D) forms an inactive drug complex
(E) inhibits acetylcholinesterase
(D) forms an inactive drug complex
Which property is characteristic of the sympathetic
nervous system?
(A) discrete activation of specific organs
(B) long preganglionic neurons
(C) action terminated by cholinesterase
(D) inhibits the enteric nervous system
(E) activated by increased arterial blood pressure
(D) inhibits the enteric nervous system
A man is given a drug that inhibits the synthesis of
norepinephrine. Which response would result from this
treatment?
(A) diarrhea
(B) bronchodilation
(C) renin secretion
(D) decreased heart rate
(E) salivation
(D) decreased heart rate
A man with diabetic autonomic neuropathy complains
of dizziness and fainting when arising from bed in the
morning. Which drug would be most beneficial to this
patient?
(A) dobutamine
(B) albuterol
(C) midodrine
(D) clonidine
(E) isoproterenol
(C) midodrine
A woman is given topical ocular apraclonidine after
cataract surgery. Which mechanism is responsible for
the desired effect?
(A) inhibition of adenylyl cyclase
(B) activation of adenylyl cyclase
(C) activation of phospholipase C
(D) inhibition of phospholipase C
(E) release of calcium from the sarcoplasmic reticulum
(A) inhibition of adenylyl cyclase
A child with asthma is being treated with albuterol to
prevent bronchospasm. Which side effect is typically
associated with this drug?
(A) sedation
(B) rapid heart rate
(C) muscle weakness
(D) low blood pressure
(E) blurred vision
(B) rapid heart rate
After being stung by a bee, a child is given an
intramuscular injection of epinephrine. Which action
would lead to bronchodilation?
(A) increased cAMP levels
(B) increased cyclic guanosine monophosphate
(cGMP) levels
(C) increased IP3 levels
(D) calcium influx
(E) sequestration of calcium
(A) increased cAMP levels
A woman experiences pain and ischemia in her finger
after accidentally injecting it with epinephrine that she
carries for emergency treatment of severe allergic
reactions.
(A) alfuzosin
(B) carvedilol
(C) betaxolol
(D) phenoxybenzamine
(E) phentolamine
(E) phentolamine
A man complains of urinary urgency, frequency, and
nocturia and is found to have enlargement of the
prostate gland.
(A) alfuzosin
(B) carvedilol
(C) betaxolol
(D) phenoxybenzamine
(E) phentolamine
(A) alfuzosin
A patient with essential hypertension requires a drug
that reduces both cardiac output and peripheral
resistance.
(A) alfuzosin
(B) carvedilol
(C) betaxolol
(D) phenoxybenzamine
(E) phentolamine
(B) carvedilol
A man with episodic severe hypertension is found to
have markedly elevated levels of epinephrine and
norepinephrine metabolites in his urine and needs a
long-acting drug to lower blood pressure before surgery.
(A) alfuzosin
(B) carvedilol
(C) betaxolol
(D) phenoxybenzamine
(E) phentolamine
(D) phenoxybenzamine
Which drug is most likely to slow recovery from
hypoglycemia in a diabetic patient who has taken an
excessive dose of insulin?
(A) metoprolol
(B) doxazosin
(C) propranolol
(D) phenoxybenzamine
(E) atenolol
(C) propranolol
A 65-year-old man with the diagnosis of Alzheimer’s disease is being treated with donepezil. This drug acts by which of the following mechanisms?
A. Stimulating the release of acetylcholine
B. Blocking the reuptake of norepinephrine
C. Inhibiting monoamine oxidase
D. Blocking the release of acetylcholine
E. Inhibiting acetylcholinesterase
E. Inhibiting acetylcholinesterase
Norepinephrine is synthesized from which amino acid
tyrosine
Norepinephrine activates what?
post synaptic alpha and beta adrenoceptors as well as presynaptic auto-receptors
How is Norepinephrine removed
neuronal uptake via the catecholamine transporter protein
