Test 4 Old Test Questions

Question 1

in areas where dopamine are low drug increases dopamine by activating the receptors. where dopamine levels are high, it causes a dose-dependent, reversible decrease in dopaminergic activity by blocking the receptors. this drug is best characterized by

Answer 1

partial agonist,

intrinsic activity between 0-1

Question 2

term used to describe the response or effect of a drug can elicit is called

Answer 2

efficacy

Question 3

the _______ the drug concentration needed to produce __________, the _______ the drug

Answer 3

the lower the drug concentration needed to produce a desired effect, the more potent the drug

Question 4

T/F efficacy of agonist is partly dependent on the total number of target receptors on the tissue/organ of interest

Answer 4

True

Question 5

which of the following will promote the greatest effect with the least amount of drug

Answer 5

high intrinsic activity, high receptor number, high affinity

Question 6

T/F partial agonists, by definition, have low affinity

Answer 6

True

Question 7

what type of drug would have 0 maximal effect as there is an increase of receptors bound by this drug

Answer 7

antagonist

Question 8

Kd is to _____ as EC50 is to _____

Answer 8

Kd is to affinity as EC50 is to potency

Question 9

as kd (inc/dec), affinity (inc/dec)

Answer 9

increases, decreases

Question 10

an antagonist is administered to a patient that results in a dose ratio of 4. this means that

Answer 10

4 times the concentration of the agonist is now required to produce the same response compared to if the antagonist were absent

Question 11

kd definition

Answer 11

ligand concentration which half of the target receptor population is occupied at equilibrium

Question 12

fractional receptor occupancy is dependent on _____ of the drug

Answer 12

affinity and concentration

Question 13

which curves have the highest efficacy when looking at a graph

Answer 13

the ones with the largest Emax

Question 14

drug A has a kd of 0.1 microM, drug B has a kd of 30 microM. Why might this be?

Answer 14

drug A has a higher affinity for the receptor than drug B

Question 15

as EC50 increases, Emax _____

Answer 15

remains the same

Question 16

as kd increases, Bmax ______

Answer 16

remains the same

Question 17

equation for finding kd

Answer 17

koff/kon

L * R / (LR)

Question 18

EC50 is defined as

Answer 18

the ligand concentration at which half of the maximum reaction response is achieved

Question 19

if compound A and compound B have the same Emax and Compound B is more potent than compound A what must be true

Answer 19

Compound B has a lower EC50 than compound A

Question 20

the ED50 for a receptor agonist is 40mg. this means that

Answer 20

40mg is needed to effectively treat half of the study population

Question 21

T/F partial agonists have a low affinity

Answer 21

false

Question 22

what is the primary purpose of a drug-receptor binding curve

Answer 22

to describe receptor binding as a function of drug concentration

Question 23

a graded dose response tells us about the _____ and ______ of a drug while a quantal dose response curve tells us about _______

Answer 23

a graded dose response tells us about the efficacy and potency of a drug while a quantal dose response curve tells us about safety

Question 24

intrinsic activity is:

Answer 24

the relative ability of a ligand-receptor complex to produce a biological response

Question 25

T/F when dosed at high enough concentration a partial agonist can exhibit the same maximal efficacy as a full agonist

Answer 25

False

Question 26

more potent drugs have ____ kd and ____ affinity

Answer 26

more potent drugs have lower kd and higher affinity

Question 27

the presence of a competitive agonist along with a full agonist has what effect

Answer 27

reduces the potency but not the efficacy of the agonist

Question 28

the clinical effectiveness of a drug depends on the drug’s

Answer 28

maximal efficacy

Question 29

T/F drug potency is related to the drugs affinity for a receptor while efficacy is related to the proportion of receptors activated

Answer 29

True

Question 30

T/F the efficacy of an antagonist is decreased in the presence of a noncompetitive antagonist

Answer 30

True

Question 31

T/F a partial agonist can reach 100% max effect of a full agonist only at 100% receptor occupancy

Answer 31

False

Question 32

T/F the difference between two different drugs can be obtained from a quantal response curve

Answer 32

False

Question 33

what best describes a quantal dose response curve

Answer 33

population of subjects increasing doses of drug to determine the dose needed to produce a desired effect

Question 34

down-regulation is:

Answer 34

usually prolonged agonist exposure, likely lead to a decrease in maximal attainable response, will require a greater dose of agonist in order to achieve the same response prior to down regulation

Question 35

the graph will shift right when drug A is a full agonist and drug B is added that is _____

Answer 35

1. a partial agonist for the receptor
2. an antagonist for the drug for the receptor
3. a full agonist for the receptor

Question 36

T/F drug x and drug y have the same affinities for the receptor so they will have the same effect

Answer 36

False

Question 37

T/F drug x and drug y both require the same dose for a specific response, therefore they have equivalent potencies for this response

Answer 37

True

Question 38

T/F drug X has a lower EC50 than Drug y, therefore Drug Y has a greater efficacy than Drug X

Answer 38

False

Question 39

the graph will shift right when drug A is a full agonist and drug B that is added is____

Answer 39

enhances the ability of the initial drug to activate the receptor

Question 40

T/F a partial agonist can be more potent than a full agonist in producing a specific response

Answer 40

True

Question 41

If compound A and compound B have the same Emax, compound B is more potent than compound B, which must be true?

Answer 41

compound B must have a lower EC50 than compound A

Question 42

what is true if two drugs have equal affinities for the same target receptor

Answer 42

both drugs will occupy the same percentage of receptors at identical concentration