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12 Cards in this Set
- Front
- Back
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1. Botulinum toxin causes paralysis by
a. Inhibiting choline acetyltransferase b. Blocking transport of choline into neurons c. Blocking release of acetylcholine from storage vesicles d. Inhibiting acetylcholinesterase e. Blocking the synapse at ganglia |
The answer is C. Botulinum toxin blocks calcium-deendent exocytosis of acetylcholine from storage vesicles, producing paralysis.
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2. Which of the following neurotransmitters interacts with guanethidine?
a. Acetylcholine b. Epinephrine c. Dopamine d. Norepinephrine e. Serotonin |
The answer is D. Guanethidine blocks the release of norepinephrine from storage vesicles into the nerve terminals.
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3. What is the mechanism of action of cocaine?
a. Propagation of action of norepinephrine by inhibiting its active transport from the synapse b. Oxidative deamination of norepinephrine in nerve terminals and the effector cells c. Inhibition of metabolism of norepinephrine in nerve terminals d. Potentiation of tyrosine hydroxylase, the rate limiting enzyme in the synthesis of norepinephrine e. Promotion of release of norepinephrine from adrenergic nerve endings |
The answer is A. Cocaine is a potent inhibitor of norepinephrine uptake, a process that normally terminates norepinephrine’s action.
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4. What intracellular effect does albuterol, a ß2-agonist, produce?
a. Allows passage of sodium through a ligand-gated ion channel b. Activates Gs-protein, resulting in stimulation of adenylyl cyclase c. Activates Gq-protein, resulting in increase of phosphatidylinositol and calcium mobilization d. Activates Gi-protein, resulting in inhibition of adenylyl cyclase e. Binds to μ-receptors in the specific areas of the brain |
The answer is B. ß2-agonists, like albuterol, activate Gs-protein, which results in stimulation of adenylyl cyclase, with subsequent in intracellular cAMP.
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5. What class of medications does methacholine belong to?
a. Nicotinic blockers b. α-Agonists c. ß1-Blockers d. ß2-Blockers e. Muscarinic agonists |
The answer is E. Methacholine is a type of muscarinic receptor agonist. The methacholine challenge test is used clinically to diagnose exercise induced asthma because of its ability to cause brief bronchospasm.
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6. A 38-year-old farmer is brought to the ER by his wife with symptoms of sudden difficulty breathing, sweatiness and anxiety. He was spraying insecticide when this happened. It has been 25 minutes since the symptoms started. Patient is emergently intubated and given atropine and another medication that acts to reactivate acetylcholinesterase. What medication is it?
a. Physostigmine b. Propranolol c. Pralidoxime d. Phenylephrine e. Pancuronium |
The answer is C. Acetylcholinesterase reactivator pralidoxime has to be given within 30minutes of exposure to insecticide because of the effects of “aging” (i.e. strengthening of the alkylphosphoryl-serine bond formed between AChE and organophosphate).
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7. Oxybutynin works by
a. Inhibiting acetylcholinesterase at muscarinic and nicotinic receptors b. Causing a neuromuscular blockade c. Antagonizing α1-adrenoreceptors d. Binding to muscarinic receptors e. Activating ß2-adrenoreceptors |
The answer is D. Oxybutynin acts by binding to muscarinic receptors located on the detrusor muscle of the bladder, suppressing involuntary contraction of the muscle.
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8. A 78-year-old male with Parkinson’s disease experiences worsening of his symptoms. He is already taking levodopa. Since the disease is characterized by degeneration of dopaminergic neurons, leading to the lack of inhibition of cholinergic neurons, the addition of which medications in likely to help alleviate the patient’s symptoms?
a. Benztropine b. Reserpine c. Doxazocin d. Timolol e. Tubocurarine |
The answer is A. Benztropine, an antimuscarinic agent, is used as an adjunct for treatment of Parkinson’s disease.
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9. A 66 year-old female with a long history of heavy smoking presents to her doctor with complaints of shortness of breath and chronic coughing that has been present for about 2 years and has been worsening in frequency. The doctor decides to prescribe a bronchodilator agent that has minimal cardiac side effects, since the patient has an extensive cardiac history. Which medication did the doctor likely prescribe?
a. Albuterol b. Prazosin c. Atenolol d. Ipratropium e. Pseudoephedrine |
The answer is D. Ipratropium bromide is used extensively for chronic obstructive pulmonary disease, which is the most likely diagnosis in this case.
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10. From the list below, choose the depolarizing neuromuscular blocker most likely to be used in “rapid sequence intubation,” a procedure that is done when the stomach contents have a high risk of refluxing and causing aspiration.
a. Baclofen b. Succinylcholine c. Neostigmine d. Homatropine e. Pralidoxime |
The answer is B. Succinylcholine is a depolarizing neuromuscular blocker that is used in rapid-sequence intubation, as well as other procedures. It quickly relaxes all the muscles in the body, allowing a prompt intubation to prevent the reflux of gastric contents into the trachea.
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11. Ephedra (ephedrine) causes increased blood pressure by
a. Indirect action on cholinergic receptors b. Blockade of adrenergic receptors c. Stimulation of release of epinephrine d. Inhibition of reuptake of catecholamines e. Direct action on dopamine receptors |
The answer is C. Ephedrine acts indirectly to release norepinephrine from nerve terminals, causing effects similar to those of catecholamines, including elevated blood pressure. This potentially dangerous agent may soon be removed from the market because of an increasing number of deaths being reported as caused by this agent.
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12. A 34 year-old carpenter presents to the ER after an accident in which he inadvertently chopped off the tip of his index finger. He is taken to the OR for reattachment of the digit, and after sedation, a local anesthetic is administered around the site of the injury. The local anesthetic used in the procedure did not contain any epinephrine, as it usually does for most surgical procedures. The reason for this is
a. Epinephrine causes increased blood loss during delicate surgery b. Epinephrine causes swelling of the tissues, making surgery more challenging c. Epinephrine is contraindicated in emergency surgery d. Epinephrine causes vasoconstriction, which can lead to vascular ischemia in digits e. Epinephrine can cause hypertension when administered with sedative agents |
The answer is D. Epinephrine is contraindicated as an anesthetic adjuvant for surgeries involving most facial structures, digits and the penis, because of this risk of vascular compromise.
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