Valley Quiz - PERIPHERAL NERVOUS SYSTEM Flashcards
Esmolol (Brevibloc) works primarily by competitively antagonizing what adrenergic receptor(s)? a. Alpha l b. Beta 1 C. Beta 2 d. Alpha 1, Beta 1
b. Beta 1
Postsynaptic nicotinic receptors are found at each of the following sites EXCEPT:
a. adrenal medulla.
b. sinoatrial node.
c. autonomic ganglia.
d. skeletal muscle motor end-plate.
B sinoatrial node
The effects of norepinephrine released from sympathetic postganglionic neurons are terminated mainly by
a. metabolism by MAO in the synaptic cleft.
b. metabolism by COMT in the synaptic cleft.
c. diffusion from the synaptic cleft into the blood stream.
d. reuptake by the nerve terminal.
D reuptake by the nerve terminal.
Release of neurotransmitter requires the entry of what substance into the nerve terminal?
a. Sodium
b. Potassium
c. Magnesium
d. Calcium
D Calcium
Which agonist listed below is largely devoid of beta2-adrenergic activity?
a. lsoproterenol
b. Terbutaline
c. Epinephrine
d. Norepinephrine
D Norepinephrine
The effects of ephedrine are due mostly to its
a. stimulation of the nerve terminal to release norepinephrine.
b. direct stimulation of a 1 and a 2 receptors.
c. direct stimulation of B1 and B2 receptors.
d. direct stimulation of a1, B1 and B2 receptors.
A stimulation of the nerve terminal to release norepinephrine.
Low levels of circulating epinephrine cause
a. a reflex decrease in heart rate.
b. a decrease in systolic blood pressure.
c. a decrease in systemic vascular resistance.
d. an increase in diastolic blood pressure.
C a decrease in systemic vascular resistance.
A patient chronically taking propranolol for hypertension is to undergo anesthesia and surgery. His last dose of propranolol was two hours before surgery. During the case, you would be cautious about
administering which of the following drugs?
a. Furosemide
b. Phenylephrine
c. Nitroglycerin
d. Hydralazine
B Phenylephrine
In the patient who is chronically beta-blocked, the beta receptors
a. increase in number.
b. decrease in number.
c. become hypersensitive to beta-adrenergic agonists.
d. become insensitive to beta-adrenergic agonists.
A increase in number. (UP REGULATION)
Alpha-adrenergic receptor blockade produces
a. an increase in systemic vascular resistance.
b. bronchoconstriction.
c. venodilation and a decrease in venous return.
d. an increase in heart rate.
C Venodilation and a decrease in venous return.
You would consider avoiding which of the following adrenergic antagonists in the asthmatic?
a. Labetalol
b. Esmolol
c. Yohimbine
d. Phentolamine
A Labetalol
Which intravenous general anesthetic would you most avoid in the beta-blocked patient?
a. Methohexital
b. Alfentanil
c. Ketamine
d. Propofol
C Ketamine
A farmer who one hour ago was spraying his crops with organophosphate insecticide complains of
abdominal cramps, muscle weakness, and blurred vision. He is wheezing and bradycardic. Treatment
of this condition might reasonably include each of the following agents EXCEPT:
a. physostigmine.
b. atropine.
c. diazepam.
d. pralidoxime.
A physostigmine
Which second messenger promotes bronchoconstriction?
a. Cyclic guanosine monophosphate (cGMP)
b. Inositol triphosphate (IP 3)
c. Cyclic adenosine monophosphate (cAMP)
d. Calmodulin
B inositol triphosphate (IP 3)
Which of the following agents produces the greatest increase in heart rate?
a. Scopolamine
b. Glycopyrrolate
c. Atropine
d. Pilocarpine
C Atropine