Pharmacology II

Question 1

most FDA approved drugs target which aspect of your body?

Answer 1

proteins

Question 2

which proteins do drugs target?

Answer 2

receptors (agonist, antagonist, and inverse agonist), ion channels, enzymes, and carriers

Question 3

agonist drugs mimic/block the effects of the endogenous agonists

Answer 3

mimic

Question 4

antagonist drugs mimic/block the effects of the endogenous agonists

Answer 4

block

Question 5

Kd

Answer 5

dissociation constant; concentration of drug for which 50% of receptors are occupied; direct reflection of affinity for the drug

Question 6

x-axis

Answer 6

usually drug concentration

Question 7

hill-langmuir equation

Answer 7

Y = [D]/ (Kd + [D]) Y (fraction bound to receptor) D = drug

Question 8

the lower the Kd the more potent/efficacy the drug has

Answer 8

potent

Question 9

potency

Answer 9

how much drug is needed for reaction

Question 10

How would increased potency affect kd and affinity?

Answer 10

lower Kd = higher affinity

Question 11

How would decreased potency affect kd and affinity?

Answer 11

higher kd = lower affinity

Question 12

Does efficacy and potency correlate?

Answer 12

they do not necessarily correlate; there are drugs that can be more effective at lower potencies and vice versa

Question 13

why does receptor occupancy not necessarily affect effectiveness?

Answer 13

signal amplification allows a smaller number of receptor occupancy for a larger reaction

Question 14

receptor reserve

Answer 14

receptors that can bind agonist but do not have to to reach maximal effect

Question 15

two types of antagonist drug molecules

Answer 15

competitive and noncompetitive

Question 16

competitive antagonist

Answer 16

compete for the same spot as the endogenous molecule; binds reversibly

Question 17

two types of non-competitive antagonist

Answer 17

1. reversible 2. irreversible

Question 18

how does a competitive antagonist affect the potency and efficacy?

Answer 18

decrease in potency same efficacy

Question 19

how would a non-competitive antagonist affect potency and efficacy?

Answer 19

decrease in efficacy

Question 20

full agonist

Answer 20

elicits the maximal response from its receptor

Question 21

partial agonist

Answer 21

elicits sub-maximal response form its receptor

Question 22

neutral antagonist

Answer 22

decreases endogenous agonist but has no effect itself

Question 23

inverse agonist

Answer 23

inhibits the basal activity of a receptor in the absence of endogenous agoinist; can also be competitive antagonist and block the effects of endogenous agonists

Question 24

inverse agonist and competitive antagonist examples

Answer 24

1. metoprolol: cardio- hypertension 2. losartan: cardio- hypertension 3. famotidine- GI- histamine blocker 4. naloxone- neuro- emergency treatment for heroin/opiod overdose 5. risperidone GI- histamine blocker

Question 25

dose-response curves are useful for describing effects that are **continuous/quantal**

Answer 25

continuous ex. pain, blood pressure, anxiety

Question 26

what does a does curve mean when the variable is quantal?

Answer 26

the curve shows the % of patients; uses a curve to describe a population

Question 27

therapeutic window

Answer 27

the dosage of drug from the minimum therapeutic effect to the minimum toxic does

Question 28

Therapeutic index (TI)

Answer 28

TD50 (toxic drug concentration where 50% is bound to receptor)/ ED50 (effective drug concentration where 50 % is bound to the receptors) or LD50 (lethal) / ED50

Question 29

higher or lower therapeutic index is better?

Answer 29

higher

Question 30

Why would the sape of a dose-response curve be different for therapeutic versus toxic effects?

Answer 30

different receptors may accound for therapeutic and toxic effects

Question 31

How is the therapeutic index affected if different receptors are used for therapeutic and toxic effects?

Answer 31

TI would grossly overestimate the safety of the drug

Question 32

certain saftey factors (CSF)

Answer 32

LD1 (lethal dose one)/ TD99 (therapeutic effect 99) higher is better

Question 33

If you have drug A = 10 and drug B = 5 what is the overall synergy effect?

Answer 33

\> 15

Question 34

If you have drug A = 10 and drug B = 5 what is the overall additive effect?

Answer 34

15

Question 35

If you have drug A = 10 and drug B = 5 what is the overall antagonist effect?

Answer 35

\< 15

Question 36

potentiation

Answer 36

when drug A has a therapeutic effect and drug B does not have any therapeutic effect but helps increase the therapeutic affect of drug A

Question 37

example of potentiation

Answer 37

cephlasporin/penicillin and probenecid

Question 38

tolerance/desensitizaton

Answer 38

reduced effect with continued use of drug over a period of time

Question 39

tachyphylaxis

Answer 39

short-term tolerance/desensitization leaving durg less effective shortly after given due to desensitizatoin

Question 40

casues of desensitization

Answer 40

1. receptor inactivation - uncoupling from signaling cascade 2. receptor internalization via endosomes 3. receptor down regulation via lysosome and break up

Question 41

how does tolerance/desensitization affect the dose response curve?

Answer 41

could decrease potency and eventually decrease eficacy