Pharmacodynamics Flashcards
What is pharmacodynamics?
The effect of the drug on the body and how they act to produce these affects.
What term defines “the effect of a drug on the body”?
Pharmacodynamics
What is a drug and and what does it do?
Molecules that produce an effect on the body by interacting with target molecules (usually proteins)
When bound to a target proetein an alteration of physiological processes occur
What are the 2 systems which are involved in physiological communication? Which is faster?
The Central Nervous System
The Endocrine System
CNS is faster
By what means does the CNS aid in physiological communication?
Impulses and neurotransmitters
By what means does the endocrine system aid in physiological communication?
hormones
Which system uses impulses and neurotransmitters for physiological communication?
Central Nervous System
Which system uses hormones for physiological communication?
Endocrine System
What is the collective term for neurotransmitters and and hormones?
first messengers
What is a first messenger?
An EXTRAcellular molecule which initiates intracellular activity by binding onto target proteins/receptors on cell surface.
What term describes an “extracellular molecule which binds onto target cell-receptors to initiatesintracellular activity”?
first messengers
What is a second messenger?
An intracellular molecule which relays signals from extracellular molecules thus mediating intracelluar activity by activating or inhibiting enzymes within the cell
What term describes an “An intracellular molecule which acts a relay for signals from a first messenger”?
second messengers
How do second messengers work?
by activating or inhibiting enzymes within the cell thus signalling the transcription of certain genes.
What type of messenger is calcium?
second messenger
Where can specific recptors be found within a cell?
plasma membrane
cytoplasm
nucleus
What are the 4 levels which decribe the physiological effect of a drug?
It’s effect on the whole body
Certain organ systems
target cells within the organ system
molecular target within cellls
Why should drugs be as specific as possible?
To reduce the secondary effect on other organ systems
What is a target protein?
a protein molecule which allows other molecules (ligand) to bind to it.
What is a ligand?
a general term for a molecule which binds onto target proteins.
What term describes “a protein molecule which allows other molecules to bind to it”?
target protein
What is the general term describes “a molecule which binds onto target proteins”?
ligands
In what way can ligands binding to target proteins affect biological process
increase, decrease or alter biological processes
What is an endogenous ligand?
a ligand produced inside the body
What is an exogenous ligand?
a ligand produced outside the body.
What term describes “a ligand prodcuced inside the body”?
endogenous ligand
What term describes “a ligand produced outside the body”?
exogenous ligand
What type of ligands are drugs?
exogenous
What are the 4 categories of target proteins?
Classic receptor
Enzyme
Ion channels
membrane transporters
Classic receptors, Enzyme, Ion channels and membrane transporters are all examples of what?
target proteins
What is a classic receptor?
a macromolecule which is part of the cell membrane to which a drug binds
What macromolecule is part of the cell membrane and which a drug binds to?
Classic receptor
What is an Enzyme?
A macromolecule whicg increases the rate of metabolic reactions in the body.
What macromolecule increases the rate of metabolic reactions in the body?
Enzymes
Describe how ion-channels work in pharmacodynamics.
drugs INTERACT with target protein causing ion-channel to open or close, altering flow of ions across membrane and thus potential difference. This in turn affect physiological changes.
Describe how membrane transporters work in pharmacodynamics.
they transport molecules across a cell membrane via passive or active transport.
Why might it take a while for a drug to have an effect on the whole physiological system?
drugs first make an affect on a molecular level (target proetin) which in itself are part of larger more complex physiological systems.
what determines the specificity of a target protein (classic receptor)?
the combination of amino acids which in turn affect the 3 dimensional structure of the protein.
What is meant when a combination of drugs has an additive effect?
When the overall response is equal to the sum of the responces of the individual drugs
what is the name of the effect when the overall response of a drug combination is equal to the sum of the individual responses?
Additive
What is meant when a combination of drugs has a potentiating effect?
When the overall response is greater that the sum of the responses of the drugs
What is the name of the effect when the overall response of a combined drug is greater that the sum of the responses of the individual drugs?
potentiating
What is irreversible binding?
when the target-protein ligand complex cannot dissiciate
What is affinity?
A measure of how easily a ligand binds to a target protein.
What term describes a measure of how easily a ligand binds to a target protein?
Affinity
What is an agonist?
A ligand that bind to a target protein and evokes a response.
What term describes a ligand that bind to a target protein and evokes a response?
agonist
What term describes the response produced by an agonist?
Agonistic response
What term describes a drug withh high affinity and high intrinsic activity?
An agonist
What properties make a good agonist?
high affinity and high intrinsic
activity
What term describes a drug withh high affinity and no intrinsic activity?
antagonist
What properties make a good agonist?
high affinity and no intrinsic activity
What is an antagonist?
A ligand which binds to a target protein but does not evoke a response.
What term describes a ligand which binds to a target protein but does not evoke a response?
antagonist
What is a competitive antagonist?
an antagonistic ligand which binds to the same binding site of a target protein as an agonist
What term describes an an antagonistic which binds to the same binding site of a target protein as an agonist?
competitive anatagonist
What is a non-competitive antagonist?
an antagonistic ligand which binds to a region other than the endogenous binding site, affecting the binding ability of the target protein
What term describes an antagonist which bind to a region other than the binding site of a target protein and thus affecting it’s affinity?
non-competitive anatagonist
What does the the term efficacy mean in pharmacodynamics?
A measure of the actual activity of a drug on the body
What does the term potency mean in pharmacodynamics?
It tell us the affinity of a drug for its target
What term describes a measure of the actual activity of a drug on the body
efficacy
What term describes tell us a measure of the affinity of a drug for its target
potency
