receptors

Question 1

pharmacodynamics

Answer 1

what it does to the body

Question 2

what is toxic to plasmodium and what is plasmodium

Answer 2

methylene blue

and plasmodium is a paracite that causes malaria

Question 3

a receptor is a

Answer 3

macromolecular component of a cell with which drugs interacts to produce its characteristic biological recponse

Question 4

families of receptors what are they

Answer 4

ion channels
g- proteins
tyrosine
intracellular

Question 5

properties of receptors

5 points

Answer 5

present at low conc and show saturable binding
many drugs have high affinities for their receptor
receptors show selectivity
drug receptor interactions are fully reversible
drugs are usually small molecules

Question 6

saturable binding is shown using

Answer 6

radioligand binding the drug

Question 7

selectivity is shown using

Answer 7

beta adrenoreceptors
isoprenaline > adrenaline > nora
alpha adrenoreceptors
nora > adrenaline > isoprenaline

Question 8

what separates dopamine and nora

Answer 8

1 OH group

Question 9

what irreversibly bind to receptors

and how

Answer 9

phenoxybenzamine

acylates

Question 10

what kind of bonds to receptors make with their drugs

Answer 10

weak bonds

Question 11

receptor structure is not ——

and antagonists do not ——

Answer 11

ridged

cause conformational changes

Question 12

quantitative drug receptor interaction

what are the 3

Answer 12

assume law of mass action
assume that only a negligible amount of total drug is bound
at equilibrium

Question 13

law of mass action

Answer 13

rate of reaction is directly proportional to product of the reactant

Question 14

assume that only a negligible amount of total drug is bound

Answer 14

density of receptors are so small that we assume that all the drug is bound

Question 15

+ve cooperation ACH what is it

Answer 15

1 molecule not sufficient to open channel

it increases affinity for the second channel to bind ACH

Question 16

-ve cooperation agonist what happens

Answer 16

agonist binds and activates G protein

Question 17

occupancy theory

Answer 17

response is proportional to number of receptors occupied

Question 18

pD2 what is it

Answer 18

-log (Kd)

determines the affinity of an agonist for its receptor

Question 19

high pD2 act at

and pD2 is always

Answer 19

low conc

always positive

Question 20

2 types of antagonist

Answer 20

competitive and

non competitive

Question 21

competitive inhibitor what does it do and how is it overcome

Answer 21

binds in the active site out competing agonist

overcome by increasing agonist conc

Question 22

non competitive inhibitor what does it do and how is it overcome

Answer 22

binds to a different site causing conformational change of receptor
irreversible
cant be overcome

Question 23

example of non competitive inhibitor

Answer 23

hexamethonium

blocks ion channel

Question 24

competitive and non competitive differences in graph

Answer 24

comp= pD2 decreases
no change in E max
non = pD2 is not changed
E max decreases
dose response curve not parallel

Question 25

assumptions about occupancy theory

Answer 25

specific receptor for specific agonist
all agonists for given receptor can provide the same maximal response
the drug reaction rapidly reversible

Question 26

partial agonists what are they

Answer 26

bind to a receptor and produce weak responses

act as competitive antagonists of full agonists

Question 27

maximum response can be obtained when not all receptors are occupied this is

Answer 27

pseudo competitive antagonism

Question 28

Spare receptors what happens to high efficacy agonists

Answer 28

they have alot of spare receptors

Question 29

fractional occupancy is proportional to

Answer 29

the conc of drug