Definitions Flashcards
Agonist
A drug that binds to a receptor and activates it
Antagonist
A drug that binds to a receptor and produces no response
Affinity
the attraction of a drug for a receptor
Efficacy
describes how well the drug elicits a response once bound to the receptor
Intrinsic activity
the capacity of a single drug-receptor complex to evoke a response
Full agonist
produces maximum response; high efficacy
Partial agonist
cannot achieve maximum response; lower efficacy
Inverse agonist
decreases receptor activity
Reversible antagonist
binds then dissociates; may compete with agonist for binding site; surmountable;
remember competitive antagonism
Irreversible antagonist
binds and dissociates very slowly; not surmountable; inactivates a proportion of the receptor population
Competitive antagonist
binds to the receptor at the same site the agonist uses; also can alter shape of receptor when bound to make it inaccessible to the agonist
Non-competitive antagonist
binds to receptor only when agonist is not bound
Uncompetitive antagonist
binds to the receptor even when the agonist is bound
Potency
the concentration of drug required to produce a certain response
EC50
is the concentration of drug required to produce 50% of a maximum response