Download Questions for Term Test #2

Questions for Term Test #2
1. A 2-selective agonist is administered to a diabetic patient. Is this a good
treatment? Explain why / why not?
2. A patient you have been treating for hypertension by prescribing propranolol, a βadrenergic receptor antagonist (β-blocker), suddenly stops taking his medication
and develops heart palpitations and rhythm irregularities. What receptor
mechanism might explain his current problem?
a. Chronic β-blockers caused downregulation of cardiac β-receptors.
b. β-Blockers are still in his bloodstream exerting an effect one day after
stopping.
c. Chronic β-blocker treatment caused supersensitivity of cardiac βreceptors.
d. He should have been on another type of antihypertensive medication.
e. Over time, β-blocker treatment caused desensitivity of β-receptors.
3. Which one of the following statements best describes drugs classified as partial
receptor agonists?
a. Partial agonists are prodrugs that split into full agonists in the body
b. Full agonists are more potent than partial agonists
c. Partial agonists have less efficacy than full agonists
d. Partial agonists are also called negative antagonists.
e. Competitive antagonists used at low concentrations act like partial
agonists.
4. Full and partial agonists are co-administered. The observed effect is:
a. tachyphylaxis
b. synergism
c. competitive inhibition
d. pharmacodynamic tolerance
e. inverse antagonism
5. Drug A has a therapeutic interval of 10. Drug B has a therapeutic interval of 2.
Which is the safest drug? Explain why BRIEFLY. 2 marks
6. Drug A is more potent than drug B. Which of the following are true?
a. Drug A has a higher ED50 and a lower Kd than drug B.
b. Drug A has a higher ED50 and a higher Kd50 drug B.
c. Drug A has a higher efficacy and lower ED50 than drug B.
d. Drug A has a lower ED50 and a lower Kd than drug B.
e. Drug A has a higher efficacy and a lower Kd than drug B.
f. All of the above
g. None of the above
7. A drug is known to have a CSF of 42. Given that the ED99 and ED50 are 400 mg,
and 275 mg respectively, calculate the dose of drug that is lethal in 1% of the
population.
8. Draw Drug concentration vs physiological response curves for the following
drugs and the natural ligand (acetylcholine) given the following information:
KD Type of agonist
Acetylcholine 1 uM full
Zx120 5 uM partial (50%)
ZQ100 1 uM full
WY135 7 uM inverse (-10%)
9. A 48-year-old man is diagnosed with Sjögren's syndrome, which is characterized by
chronic dry mouth due to undersecretion of saliva (xerostomia). Which one of the
following agents might best treat his condition?
a) muscarinic antagonist
b) reversible acetylcholinesterase inhibitor
c) irreversible acetylcholinesterase inhibitor
d) muscarinic agonist
e) 1 adrenergic receptor agonist