Pharmacodynamics Flashcards
Define pharmacodynamics
Study of what drugs do to the body
Pharmacokinetics is
Pharmacodynamics is
A drug is a xenobiotic that induces an effect typically by interacting with an endogenous target molecule, also called a _____
Receptor
The ____ can be an enzyme, nucleic acid, or a special membrane brown protein
Receptor
A large class of drug receptors are ______ _____, a molecule produced by the body (endogenous). Examples include ligand gated ion channels, G protein coupled receptors
Physiological receptors
The second largest class of drug targets are _____. Example is penicillin, ACE Inhibitors
Enzymes
The third major class of drug receptors are _____.
Nucleic acids
Drug dose response graph. The drug concentration is on the X axis and a _____ on the Y axis
Biological effect
Fischer projection is a ___ and ____ model of thinking about enzyme and substrate interaction. This model has limitations
Lock and key
_____ is the equilibrium dissociation constant of a drug-receptor complex. ______ is the reciprocal of kD. If affinity is high, the dissociation constant will be low.
kD
Affinity
Low affinity requires a ____ concentration of molecules
Higher
The _____ is the free drug concentration at which half of the receptors are drug bound
KD (similar to Km)
Different drugs may possess distinct _____ for a common target (receptor)
Potencies
Drug A is more potent than drug B. It takes less concentration of drug A to reach the same effect
A lower ED50 of a drug means the _____ the potency.
Higher
The _____ opens the lock, the _____ does not open the lock. These two things can compete for each other.
Agonist
Antagonist
Drug A is an agonist, Drug B is an antagonist
_____ ____ can be overcome if sufficiently high concentration of agonist is present
Competitive antagonist
____ _____ cannot be overcome even in the presence of extremely high agonist levels, sometimes considered insurmountable antagonist. Has no effect on the ED50
Non competitive antagonist
_____ agonist, not able to produce the full effect as a full agonist.
Partial
In this picture, both drugs have identical potencies, meaning they reached half-maximal effect observed at identical doses
Fentanyl is a ____ agonist, ibuprofen is a _____ agonist. Fentanyl is more _____.
Full
Partial
Efficacious
Difference in drug efficacy will have different levels of _____ on a graph. Different drug potencies will effectually reach the same effect levels but at different ____ levels
Effect
Dose
Fentanyl and buprenorphine are equally potent. Fentanyl and morphine are more efficacious than buprenorphine
____ ____ ____ model replaced the lock and key model
Induced fit binding
(Conformational selection binding model)
The ___ ____ model is the idea that the drug receptor can switch back and forth between the active and inactive state
Two State
____ ____ ___ is how much activity does the receptor have in the absence of ligand
Constitutive Receptor Activation
_____ receptor activity reduces the response in a system (inverse agonist). _____ receptor activity increases the level of response in a system (agonist). _____ receptor activity, the response remains the same (antagonist).
Diminished
Enhanced
Constitutive
An agonist has a higher ___to bind to the active site in a receptor and shifts towards higher level of activity. An _____ agonist has a higher affinity to the inactive site of a receptor and diminishes the level of activity. A ____ has the same affinity for both the active and inactive sites on the receptor and has no effect of the levels of activity.
Affinity
Inverse agonist
Antagonist
____ is the degree to which a drug binds to ONE receptor. Dopamine can interact with three different types of receptors.
Selectivity
Dopamine is more selective for DA1
______ dose response curve, when the dose of the drug is describe in terms of a percentage of the maximal response. _____ dose response is when a drug is described in terms of the cumulative percent of subject who exhibit an effect
Graded
Quantal
The range between the ED50 and LD50 (lethal dose) is the ____ ____
Therapeutic index
Activation of cell surface receptor is associated with Intracellular production of ____ ____. This is the concept of signal transduction
Second messengers
Second messengers can result in massive ____ of signaling
Amplification
The largest class of receptors are ____ .
They bind endogenous and therapeutic molecules
G protein
Some important second messenger molecules include:
Ca++, cAMP, IP3, DAG, acetylcholine, nicotine, varenicline
Receptor protein _____ ____ and _____ receptors are able to initiate a phosphorylation cascade. This is an example of a signal transduction pathway.
Tyrosine kinases
Cytokine
