Pharmacodynamics - Drug Receptor Interactions

Question 1

What is the purpose of secondary messengers?

Answer 1

amplify cellular signals to trigger a cellular response cascade

Question 2

what describes the tendency of a drug to combine with a particular kind of receptor

Answer 2

affinity

Question 3

what does affinity rely on

Answer 3

chemical structure to create a strong binding force (covalent/ ionic bond)

Question 4

what refers to the maximal effect the drug can produce

Answer 4

efficacy

Question 5

what does drug efficacy depend on

Answer 5

-conformational changes in receptors
-drug-receptor complexes

Question 6

just because a drug has efficacy, will there always be an observable side effect?

Answer 6

no - efficacy only measures the changes made by a drug to a receptor
clinical efficacy will show the side effects while intrinsic efficacy does not

Question 7

what possesses affinity for a particular receptor, causing a change that results in an observable effect

Answer 7

agonist

Question 8

what is a drug that blocks the response produced by an agonist

Answer 8

antagonist

Question 9

does an antagonist have affinity for a receptor

Answer 9

yes

Question 10

does an antagonist have intrinsic efficacy

Answer 10

no

Question 11

how does an antagonist have clinical efficacy but no intrinsic effects

Answer 11

blocking a response (to show no response) is a clinical sign
– NOTHING HAPPENING IS A SIGN –
antagonists do not cause a conformational change in the receptor is it blocking

Question 12

what are the 3 types of antagonism

Answer 12

1. receptor antagonism
2. physiologic antagonism
3. chemical antagonism

Question 13

what has intrinsic efficacy but produces an opposite effect

Answer 13

inverse agonist

Question 14

on a dose-response curve, where would you find efficacy

Answer 14

peak of the curve (maximal response)

Question 15

what is the concentration of a drug required to achieve a particular effect

Answer 15

potency

Question 16

if a drug has high potency, what type of dose is required/ needed

Answer 16

small dose

Question 17

what is the relationship between potency and affinity?

Answer 17

high potency = high affinity
- higher binding to a receptor creating more responses

Question 18

what does potency depend on

Answer 18

affinity and efficacy of a receptor

Question 19

what type of drug produces only a single effect

Answer 19

selective drug

Question 20

what is an example of a selective drug and why

Answer 20

heparin – it’s only effect is an anticoagulant

Question 21

what type of drug acts only on 1 type of receptor but can have multiple effects

Answer 21

specific drugs

Question 22

how is a specific drug able to have multiple responses with only acting on 1 type of receptor

Answer 22

these receptors can be found throughout the body in different organs

Question 23

what is an example of a specific drug

Answer 23

atropine

Question 24

what type of drug has several mechanisms of action

Answer 24

non-specific drug

Question 25

what is an example of a non-specific drug

Answer 25

acepromazine
causes sedation, antiemetic, hypotension and hypothermia