Exam 1 Quiz 2: Pharmacodynamics Pt 2

Question 1

study of the physiological and biochemical interaction of drug molecules with cell receptors in target tissue that respond to hormones

Answer 1

pharmacodynamics

Question 2

receptors

Answer 2

proteins on cell surface or within cells

Question 3

ligand

Answer 3

chemical or molecule that binds to a receptor with some selectivity
can be a neurotransmitter or a drug

Question 4

distinct site on the surface of the receptor different from where neurotransmitter binds
- impacts function of the receptor

Answer 4

allosteric binding site

Question 5

strength of the bond between the drug and the receptor

- how much does the drug like the receptor

Answer 5

binding affinity

Question 6

drugs ability to alter the activity of the receptor

- what is the drug doing? is there a biological response to the drug?

Answer 6

receptor efficacy

Question 7

what is receptor efficacy typically compared to

Answer 7

endogenous ligand

• naturally occurring chemical in your body
  ex: comparing cocaine to dopamine

Question 8

has the best chemical fit (highest affinity)
attaches readily to the receptor and produces a significant biological effect
mimic the endogenous ligand

Answer 8

receptor agonist

Question 9

do receptor agonists always have an excitatory response? explain

Answer 9

no

it depends on the receptor, if the receptor is inhibitory you will get an IPSP

Question 10

fit receptors but produce no cellular effect (low efficacy)

can prevent active ligands from binding

Answer 10

receptor antagonists

Question 11

have intermediate efficacy - not a huge effect but still binds

Answer 11

partial agonists

Question 12

initiate biological action that is opposite to that produced by an agonist

Answer 12

inverse agonist

Question 13

2 forms of antagonists

Answer 13

competitive and noncompetitive

Question 14

bind the same site as a neurotransmitter to prevent the neurotransmitter from binding to and activating receptors

Answer 14

competitive antagonists

Question 15

do NOT prevent neurotransmitter binding
Prevent activation of receptor by binding to other sites
- interacts with endogenous ligand

Answer 15

noncompetitive antagonists

Question 16

2 types of allosteric regulators and what they are

Answer 16

positive modulators: bind to allosteric sites on receptor and INCREASE the ability of neurotransmitter to bind to and or activate the receptor (amplifies it)

negative modulators: bind to allosteric sites and DECREASE ability of neurotransmitter to bind and or activate receptor (diminishes it - like a whisper)

Question 17

upregulation vs down regulation

Answer 17

up regulation: inc # of receptors - inc chance of a biological response

down regulation: dec # receptors in response to absence of ligands or chronic activation - dec chance of biological response

Question 18

dose response curve purpose

Answer 18

how much (dose/amount) of a drug (x-axis) causes a particular effect on the body (y-axis)

Question 19

smallest dose that produces a measurable effect

Answer 19

threshold dose

Question 20

amount of drug needed to occupy all receptors (the peak)

Answer 20

maximum response

Question 21

drug dose that produces on average, a specified all or none response in 50% of the test population
- at what dose do you need to get a response from 50%

Answer 21

ED50 (effective dose 50%)

Question 22

ED100

Answer 22

dose that produces maximal effect in 100% of he population

how high of a dose do you need to give to reach 100%

Question 23

toxic dose

Answer 23

TD50

dose at which 50% of the population gets adverse reactions (side effects)

Question 24

lethal dose

Answer 24

LD50
dose at which 50% of the population die
- not seen for humans usually animals

Question 25

therapeutic index

Answer 25

TI
TD50/ED50
what range of values can we prescribe with benefits that out weigh the side effects

Question 26

amount of drug needed to produce a given effect
determined by affinity of drug for receptor and # of receptors available
determined by ED50 value

Answer 26

potency

Question 27

more potent drugs require____

Answer 27

lower doses to produce the effect

most potent is more to the left on a graph

Question 28

maximum effect/response a drug can produce what response we are getting
more drug - has no effect - but may inc side effects
highest values on graph = highest

Answer 28

efficacy

Question 29

what is the purpose of the therapeutic index

Answer 29

calculates drug safety

- provides dose range and accounts for side effects

Question 30

these can be replaced by an excess of agonist

• replace the endogenous ligand molecule
• shift potency to the right

Answer 30

competitive antagonists

Question 31

competitive antagonist example

Answer 31

naloxone is competitive antagonist of morphine

• makes it harder to produce the biological response - increases the amount fo drug needed to cause effects

Question 32

how do noncompetitive antagonists reduce the effects of agonists (3)

Answer 32

1. bind to allosteric sites
2. disturb cell membrane supporting the receptor
3. interfere with cell processes initiated by agonist

change magnitude of biological response
- can effect both potency and efficacy or jus tone or the other

Question 33

example of a noncompetitive antagonist

Answer 33

want pain relief without the sedative effects
- with these you get as close as possible to pain relief without getting the toxic side effects

• usually given to prevent an overdose

Question 34

2 drugs interact and reduce effectiveness of both drugs

Answer 34

physiological antagonism

Question 35

both drugs taken together cause a combined greater effect

Answer 35

additive effects

Question 36

combination of 2 drugs produces effects greater than the sum of their individual effects

Answer 36

potentiation (drug synergy)

Question 37

what can a longer half life lead to

Answer 37

accumulatio which increases potential for side effects and toxicity

Question 38

target therapeutic concentration is achieved only after ____

Answer 38

multiple doses

Question 39

half life determines the time needed to reach the study state plasma level which is when _____

Answer 39

absorption/distribution phase is equal to the metabolic/excretion phase