Principles of Pharmacology 2

Question 1

EC50

Answer 1

the concentration of a drug or compound that is required to produce a half-maximal effect on a biological system.

Question 2

when the EC50 of a drug is low, then the affinity is…………..

when the EC50 of a drug is high, then the affinity is………….

Answer 2

high

low

Question 3

at what concentration does a drug with a high affinity need to be used to produce optimal effect

Answer 3

low concentrations

Question 4

at what concentration does a drug with a low affinity need to be used to produce an optimal effect

Answer 4

high concentration

Question 5

potency

Answer 5

relates to how big a dose you need to give to gain a particular effect in an intact animal

Question 6

what dose is required when a drug is high in potency

Answer 6

a low dose

Question 7

if the potency of a drug is low, then what dose of it is required to produce a response

Answer 7

a high dose

Question 8

what does it mean if a drug has a high potency?

Answer 8

it means that the drug is effective at producing a specific biological or pharmacological effect at a relatively low dose or concentration

Question 9

what was the original conception(thought) of the drug-receptor interaction

Answer 9

that the drug combines with the specific receptor to produce a drug-receptor complex. This DR complex gives a certain amount of response to the tissue, therefore when all receptors are occupied the maximum response is reached

Question 10

intrinsic activity

Answer 10

It is a critical concept in pharmacology and drug development and is often used to categorize drugs or compounds based on their ability to elicit a response at a given receptor.

Question 11

types of agonists

Answer 11

full agonist
partial agonist

Question 12

full agonist

partial agonist

Answer 12

an agonist that produces the full or maximum response

an agonist that produces a partial response

Question 13

100% receptor occupancy means 100% effect, true or false

Answer 13

FALSE

Question 14

drug efficacy

Answer 14

refers to the ability of a drug to produce a desired therapeutic effect or beneficial outcome when administered under specific conditions.

Question 15

what do efficacy and intrinsic activity have in common

Answer 15

they both give an idea of the overall maximum effect of the agonist

Question 16

when can partial and full agonist log concentration curves be useful?

Answer 16

They aid in understanding and optimizing the effects of drugs, evaluating their therapeutic potential, and ensuring patient safety

Question 17

what does the choice between using a partial or full agonist depend on

Answer 17

the specific clinical scenario, desired therapeutic effects, and potential risks and side effects.

Question 18

the formula for calculating intrinsic activity

Answer 18

maximal response to test agonist/ maximal response to full agonist

Question 19

intrinsic activity ranges between?

Answer 19

0-1

Question 20

inverse agonists

Answer 20

a pharmacological compound that binds to the same receptor as an agonist (a molecule that activates the receptor) but produces the opposite effect

Question 21

differences between inverse agonists and antagonists

Answer 21

Antagonists bind to receptors but do not have intrinsic activity; they block the binding of agonists without affecting basal receptor activity. In contrast, inverse agonists actively reduce the basal activity of the receptor.

Question 22

antagonists

Answer 22

they are pharmacological compounds that bind to specific receptors or molecules in the body and block or inhibit their activation by agonists

Question 23

what are the types of antagonists?

Answer 23

chemical
physiological
pharmacological

Question 24

chemical antagonists

Answer 24

substances or compounds that act as antagonists by directly interfering with the function of a target molecule, typically without binding to a receptor.

Question 25

do chemical antagonists depend on interactions with the agonist’s receptor

Answer 25

no

Question 26

physiological antagonists

Answer 26

type of antagonism that occurs when two different physiological or pharmacological pathways produce opposing effects to regulate a specific physiological function or process

Question 27

give an example of physiological antagonism

Answer 27

Vasodilation vs. Vasoconstriction

Question 28

pharmacological antagonists

Answer 28

antagonists that combine with a receptor, do not produce a response but prevent the action of an agonist

Question 29

what are the types of pharmacological antagonists

Answer 29

competitive-reversible
competitive-irreversible
non-competitive- reversible
non-competitive-irreversible

Question 30

how can competitive antagonism be overcome

Answer 30

by giving a high enough concentration of agonist

Question 31

non-competitive antagonists

Answer 31

they bind to a receptor at an allosteric site, thereby causing a conformational change in the receptor, which reduces it’s responsiveness to the agonist

Question 32

how can irreversible antagonism be overcome?
can increasing the agonist concentration help overcome this?

Answer 32

by making new receptors through protein synthesis

no, it is useless in this case

Question 33

features of irreversible antagonism

Answer 33

can prevent the binding of the agonist

it effectively removes affected receptors from the population

maximum response to the agonist is reduced

EC50 remains the same for the unaffected receptors

The binding of the antagonist does not alter the ability of the agonist to bind to “normal” receptors

Question 35

Advantages of the sigmoidal shape of the log dose-response curve

Answer 35

A wide range of doses can be accommodated easily in the graph

Maximal response plateau is clearly defined

Central portion of the curve approximates to a straight line , allowing the collection of fewer data points to delineate the relationship accurately

Question 36

drugs with high affinity have high potency, true or false

Answer 36

true

Question 37

a drug with a low EC50 has a ……….. potency

Answer 37

high

Question 38

efficacy is dependent on?

Answer 38

intrinsic activity
drug-receptor interactions