Pharmacology 1: principles Flashcards
What is Pharmacodynamics
What a drug does to the body
What is Pharmacokinetics
The body does to a drug
Describe Affinity
The binding step. The strength of association between ligand and receptor
Describe high vs low affinity
High affinity agonists have a slow dissociation rate and Low affinity agonists have a fast dissociation rate
Describe Efficacy
The activation step. The ability of an agonist to evoke a response.
Do antagonists have affinity or efficacy or both
Antagonists have affinity but no efficacy
How do antagonists bind
To orthosteric (competitive) or allosteric (non-competitive) sites
What is the EC50?
The concentration of agonist which elicits a half-maximal response
What type of plot do we use for the EC50?
Semi-logarithmic.
How is the relationship between concentration and response described?
Sigmoidal
Describe the graph of a Potent agonist, Less Potent agonist, and a partial agonist
In competitive antagonists, in which direction is the response curve shifted?
Parallel to the Right.
Becomes less potent but with higher conc. of agonist the antagonist can be out-competed to produce the same maximal response
In non-competitive antagonists, in thich direction is the response curve shifted?
Slope Flattened.
When the agonist binds, it cannot contribute to maximal response.
With which type of antagonist does EC50 and therefore potency increase
Competitive
What is drug disposition?
The fate of drugs in the body
Absorption, distribution, metabolism, excretion
