Lecture 16 + 17: Pharmacodynamics 1 Flashcards
What is the definition of a ligand?
Substance that binds to a receptor
What is drug action determined by?
Concentration of drug molecules around receptors
Do most drugs bind reversibly or irreversibly?
Most drugs bind to receptors reversibly
What is the relationship between affinity and binding?
Higher affinity means stronger binding
What is Kd?
Concentration of ligand at which 50% of all available receptors are bound
What is Kd measure?
Index of affinity or strength of interaction
What is the relationship between Kd and affinity?
Lower Kd = higher affinity
What is the meaning of affinity?
Measure of the strength with which a ligand a drug binds to a receptor
What is the meaning of antagonist?
Ligands that have affinity for a receptor or target protein but do not produce a biological response
What is the function of antagonists?
Block effects of agonists
What is the meaning of agonists?
Substance that binds to a receptor and activates the receptor to then produce a measurable biological response
What is intrinsic efficacy?
Ability of a ligand to generate the active form of receptor
What is ligand efficacy?
Ability of ligand to cause a measurable biological response
What is clinical efficacy?
Indication of how well a treatment succeeds in achieving its aim
What is agonist potency?
Concentration of a drug that evokes 50% of its maximal response
