Pharmacodynamics

Question 1

define a drug

Answer 1

a chemical substance that interacts with a biological system to produce a physiological effect

Question 2

define drug target site

Answer 2

a protein on which a drug acts

Question 3

what are the 4 types of drug target sites

Answer 3

receptor
ion channel
transport system
enzyme

Question 4

define receptor

Answer 4

the protein molecule which a drug binds to in order to have its effect

Question 5

what are the 4 types of receptor

Answer 5

ligand-gated (T1)
G protein-coupled (T2)
kinase-linked (T3)
nuclear receptors (T4)

slower response lower down the list

Question 6

define agonist

Answer 6

ligand which stimulates a receptor

Question 7

define antagonist

Answer 7

substances which interact with receptors but cause no effect

Question 8

define affinity

Answer 8

the strength with which a drug binds to the desired receptor

Question 9

define efficacy

Answer 9

the likelihood that the antagonist will stimulate the natural response of the agonist

Question 10

what is a full agonist

Answer 10

agonist which generates a maximal response

Question 11

what is a partial agonist

Answer 11

agonist which always generates a partial response

Question 12

what is drug selectivity

Answer 12

the preference of the agonist to interact with a specific receptor

Question 13

define potency

Answer 13

depends on affinity and efficacy

lower potency requires higher dose

Question 14

what are the 4 types of drug antagonism

Answer 14

receptor blockade
physiological antagonism
chemical antagonism
pharmacokinetic antagonism

Question 15

what effect does a competitive antagonist have on a log-dose response curve

Answer 15

moves the line to the right

Question 16

what effect does an irreversible antagonist have on a log-dose response curve

Answer 16

lowers the maximum height reached

Question 17

what is drug tolerance

Answer 17

gradual decrease in responsiveness to a drug with repeated administration

Question 18

what are the 5 cellular mechanisms of tolerance

Answer 18

pharmacokinetic factors 
loss of receptors 
change in receptors 
exhaustion of mediator stores
physiological adaption