Lecture 1: Introduction to pharmacology Flashcards
What is meant by pharmacodynamics?
What a drug does to the body, including biological effects and mechanism of action.
What is meant by pharmacokinetics?
What the body does to a drug, i.e absorption, distribution, metabolism and excretion.
How do drugs act?
By binding to target molecules (Think lock and key theory where the drug is the key)
What is an agonist?
A drug that binds to a receptor to evoke a cellular response.
What is an antagonist?
A drug that blocks the action of an agonist.
Describe the action of an agonist.
The agonist binds to to the receptor and causes a conformational change in shape of the molecule, evoking a cellular response.
What is meant by “Affinity?”
- The strength of association between a ligand and receptor
- In simpler terms, the amount of time an agonist remains bound with the receptor.
What is meant by “efficacy?”
The ability of an agonist to evoke a cellular response.
Describe an agonist in terms of affinity and efficacy.
An agonist possesses both affinity and efficacy.
Describe an antagonist in terms of affinity and efficacy.
An antagonist possesses affinity but no efficacy.
What is meant by “Saturation?”
The point at which all receptors are occupied by agonist.
What is meant by “competitive antagonism?”
When the binding of the agonist and antagonist occurs at the same (orthosteric) site.
What is meant my “non-competitive antagonism?” (2)
- When the agonist binds to the orthosteric site and the antagonist binds to a separate allosteric site.
- Both molecules can be bound to their receptors, however activation cannot occur with the antagonist bound.
