Week 1 Flashcards
(18 cards)
What is the definition of a “drug” according to the sources?
Drug is a substance that interacts with biological systems to produce a change.
What is the general relationship between drugs and poisons?
All things are poison and nothing is without poison; only the dosage makes it so that something is not a poison”.
What are some common functional classes of drug targets?
Enzymes, hormone and neurotransmitter receptors, ion channels, membrane transporters, and cytoskeletal proteins. Other drug targets include DNA and RNA.
What is a “receptor” in the context of pharmacology?
A receptor is a molecule (usually a protein) that a drug binds to in order to produce its effect
What are some different ways a drug can interact with a receptor?
Drugs can act as agonists, which activate receptors, or antagonists, which block receptors.
What is the difference between an agonist and an antagonist?
An agonist activates the receptor to produce a response, while an antagonist binds to the receptor and prevents its activation.
What is the difference between a drug that binds reversibly and a drug that binds irreversibly?
A drug that binds reversibly can detach from the receptor, while a drug that binds irreversibly forms a stable bond, often covalent, with the receptor
What is the significance of the “two-state model” in drug-receptor interaction?
The “two-state model” describes how a receptor exists in either an active or an inactive state, and that the binding of a ligand shifts the equilibrium between these two states
What is a partial agonist?
A partial agonist is a drug that binds to a receptor and activates it, but it cannot achieve the same maximal response as a full agonist
What is an inverse agonist?
An inverse agonist is a drug that binds to the receptor and produces the opposite effect of an agonist, effectively reducing the receptor’s basal activity
What is a “pharmacophore”?
A pharmacophore is the collection of functional groups shared by a set of compounds that are necessary for their interaction with a receptor
What is a “eutomer”?
A eutomer is the stereoisomer of a drug with the higher affinity or activity
What is a “distomer”?
A distomer is the stereoisomer of a drug with the lower affinity or activity
What is the meaning of “orthosteric” binding?
Orthosteric binding means that a drug binds to the same site on a receptor as the receptor’s physiological ligand
What is the meaning of “allosteric” binding?
Allosteric binding means that a drug binds to a different site on a receptor than the receptor’s physiological ligand.
What is a Scatchard plot used for?
A Scatchard plot is a way to analyze binding data to determine the number and affinity of binding sites on a receptor. A linear plot indicates a single class of binding sites.
How does a covalent inhibitor affect the receptor saturation curve?
A covalent inhibitor will vertically compress the receptor saturation curve, reducing the maximal response. AKA irreversible antagonist
What is the difference between potency and efficacy?
Potency is a measure of how much drug is needed to produce a certain response, often expressed as the EC50, the concentration for 50% of the maximum effect. Efficacy is the maximum response a drug can achieve, regardless of concentration.
