3- Pharmacodynamics

Question 1

additive vs. synergistic

Answer 1

drug A = 20 drug B = 20

A+ B = 40 = additive
A+B = 90 = synergistic

Question 2

estrogen receptor

vitamin A/retinoic acid receptor

Answer 2

intracellular receptors

Question 3

bind lipophillic agents

Answer 3

intracellular receptors

Question 4

consequence of ligand binding is a change in gene activity(transcription)

Answer 4

often an intracellular receptor

Question 5

single membrane spaning domain with extracelullar ligand binding area and intracellular enzymatic activity area

Answer 5

intrinsic enzymatic activity receptor

Question 6

tyrosine kinases

Answer 6

receptor with intrinsic enzymatic activity

Question 7

epidermal growth factor receptor
insulin receptor
transforming growth factor receptor

Answer 7

receptors with intrinsic enzymatic activity

Question 8

leptin receptor
erythropoietin
interleukin-3

Answer 8

receptors that directly associate with intracellular enzymes

Question 9

nAchR

Answer 9

ligand-gated ion channel

Question 10

rhodopsin
frizzled
odorant receptors
smoothened receptors
beta adrenergic receptors

Answer 10

7MSR aka serpentine or heptahelical receptors

Question 11

can 7MSR mediate signals that are independent of gprtn signaling

Answer 11

yes

can mediate signals that require coupling to a g prtn OR are independent of gprtn signaling

Question 12

downregulation

Answer 12

continued stimulation of a receptor leads to a decreased number of receptors

Question 13

upregulation

Answer 13

continued exposure of a receptor to an inhibitor causes a increase in number of receptors

Question 14

decreased physiological response to the same amount of drug

Answer 14

tolerance

Question 15

increased physiological response to the same amount of drug

Answer 15

sensitization

Question 16

equation for dissociation constant Kd

Answer 16

kd = (concentration of drug x concentration of ligand) / concentration of receptor bound drug

Question 17

point at which half the receptors are occupied with ligand and half the receptors are free

Answer 17

Kd dissociation constant

Question 18

higher affinity = ____________ Kd

Answer 18

lower Kd

the lower the Kd (or less drug required for half maximal occupancy), the greater the binding affinity of that drug

Question 19

concentration of drug that produces a half-maximal response

Answer 19

EC50

Question 20

comparing the EC50 of drugs tells you …

Answer 20

potency

Question 21

comparing the Emax of drugs tells you …

Answer 21

efficacy

Question 22

a drug that binds to a receptor and produces a response

Answer 22

agonist

Question 23

a drug or ligand that binds to a receptor and inhibits the response produced by the agonist

Answer 23

antagonist

Question 24

compete for the same binding site

Answer 24

competitive antagonist

Question 25

bind to different sites

Answer 25

noncompetitive antagonist

Question 26

induces a shift to the right in EC50 of dose curve but max effect is still achievable

Answer 26

competitive antagonist

max effect is still achievable because the antagonist can be outcompeted with higher concentrations of agonist but the EC50 of the agonist is increased

Question 27

decrease in the maximal effect of the agonist without changing the binding affinity (EC 50 doesn’t change)

Answer 27

noncompetitive antagonist

Question 28

drug that produces a lower maximal response compared to the agonist

Answer 28

partial agonist

Question 29

overall result of increasing partial agonists =

Answer 29

blunted overall physiological response (see graphs)

Question 30

dose at which 50% of individuals exhibit a specific quantal effect

Answer 30

ED50

Question 31

dose at which 50% of individuals exhibit a toxic effect

Answer 31

TD50

Question 32

dose at which 50% of individuals die

Answer 32

LD50

Question 33

therapeutic index ID =

Answer 33

TD50 / ED50

Question 34

a higher ID = ______________ safety

Answer 34

increased safety

more wiggle room between lethal and therapeutic doses