Pharmacology MT Flashcards
Pharmacology is the study of ______ that interact with ______ through ________ process
Pharmacology is the study of substances that interact with living systems through chemical process
define medical pharmacology
the study of substances used to prevent, diagnose and treat disease
_______ is the study of undesirable effects of chemicals on living systems & ecosystems
toxicology
medical pharmacology studies _____ where as toxicology studies _____`
efficacy; side effects
Drug –> body is studied via __________
pharmacodynamics
body –> drug is studied via _________
pharmacokinetics
________ is the science of drug preparattion. and medical use of drugs in roman times (after 2500 BC)
materia medica
Francois Magendie & Claude Bernard are known for ..
developing methods of experimental physiology and pharmacology
The relation of an individuals genetic makeup to their response tot specific drugs is called _________
pharmacogenetics
What are 3 advances from the field of pharmacogenetics?
- understanding that certain diseases are inherited
- genomes of humans, animals and plants have been decoded - options for new research and treatment
- genetic techniques - gene therapy, KO mice
A new drug compound requires the discovery of a new ___________ (i.e the pathophysiological process or substrate of a disease condition)
new drug target
What occurs in in vitro studies and how long does it typically take?
Biological products and/or chemical synthesis, optimization (enzymes etc.) combine to form a lead compound.
~ 2 yrs
What is evaluated during animal testing? What occurs directly after?
Animal testing is the best model of disease for evaluating efficacy, selectivity and mechanism
- directly after: submit to a regulatory body = investigational new drug
~ 2 yrs
What does phase 1 of clinical testing evaluate? how many subjects?
Is it safe? Pharmacokinetics
20-100 subjects
What does phase 2 of clinical testing evaluate? how many subjects?
Does it work in patients w/ disease?
100-200 pt.
What does phase 3 of clinical testing evaluate? how many subjects?
does it work, double blind? (need significant effect)
randomized control trial
1000-6000 pt.
the clinical testing phase of drug development takes _- _ years
3-4 years
______ is an activator of biochemical pathway that mimics endogenous signalling
agonist
_________ stabilize receptors in an inactive form by shutting down constituent receptor
inverse agonist
______ inhibits a biological pathway by blocking endogenous signalling.
antagonist
_______ antagonist compound loosely binds to the same site as the natural ligand and inhibits natural action of ligand
competitive
_______ antagonist compound binds to _______ on the receptor and inhibits function
noncompetitive
_______ antagonist causes covalent modification of receptor
irreversible
Agonists and Antagonists require ___________ to induce change
target molecule (receptor)
a partial agonist increases ______ (compared to normal) but decreases ______ (compared to full agonist)
effect; effect size
Most rapid onset is the characteristic of ______ route drugs
IV
- large volumes often feasible
- may be painful
- used for when you cant take meds on daily basis describes which drug route
intramuscular
Smaller volumes than IM - may be painful is the characteristic of ______ route drugs
Subcutaneous (SC)
most convenient route with a significant first past effect is the characteristic of ______ route drugs
Oral (PO)
Less first pass effect than PO is the characteristic of ______ route drugs
Parenteral Rectal (PR)
Often very rapid onset (2nd to IV) is the characteristic of ______ route drugs
inhalation
Slow absorption used for lack of first pass effect and prolonged duration of action is the characteristic of ______ route drugs
Transdermal
The fact that drugs exist in the form of organic and inorganic compounds is important for _______
how the body handles the drug
Drug size is an important factor for ______
administration
rational drug design describes …
design based on known structure of ligand & receptor
Allosteric Activator + Agonist = ______ response
max
Agonist + Competitive inhibitor = _____
Right shift - same max response but don’t increase max effect
Agonist + Allosteric inhibitor = ______
decrease below the use of a competitive inhibitor
What occurs when an agonist binds to a receptor
electrostatic changes = conformational change of receptor
ex. GPCR opening ion channel
4 process that are involved in termination of drug action
- dissociation of drug from receptor = terminate effect (ex. ionotropic receptor)
- action persists after drug has dissociated (ex. GPCR, phosphorylation)
- covalent bond - drug receptor complex must be destroyed and new receptors synthesized
- desensitization mechanisms - receptor mineralization
How do receptors determine the drug dose/ conc. & the effect
dose/conc: receptor affinity for a drug
effect: total # of receptors
____ is the maximal response that can be produced by a drug
Emax
____ is he concentration of drug that produced 50% of maximal effect
EC50
What is the eqn for the effect observed at conc. C
Constitutive activity describes… and is inhibited by ______
…the fact that some receptors are active w/o being bound to endogenous ligands.. inhibited by inverse agonist
____ can be used to measure he potency between different drugs in a log scale
EC50 - the drug conc.(on x axis) which induces a 1/2 max effect (Emax) response
responses to low doses usually _____ in _____ proportion to dose. Response increment _______ as dose increases
increase ; direct ; diminish
How do we chose among drugs and determine appropriate dosing? (2)
• pharmacologic potency (position dose axis)
• maximal efficacy (end point on response axis)
the maximum effect is driven by …. and reduced by increasing the concentration of _____
..the total # of receptors activated ; antagonist
Low doses of antagonists affect the agonist concentration effect curve by _______ whereas high dose antagonists cause it to _______
shift to the right ; reduce max response and R shift
EC50 is the dose required for ______ to experience 50% ____ effect and is seen in ______
ED50 is the dose required for 50% __________ to obtain the ____ effect and is seen in ______
individual; max; lab tests
of the population; therapeutic; clinical effects
IC50 is the measure of the _______of a substance in inhibiting a ____________ by 50%
potency; specific biological or biochemical function
You want IC50 to be high when you want to see ____ activity whereas you want EC50 to be high when you want to see _____ activity
decreased; increased
if Kd is ___ binding affinity is ____
low; high
___ is the concentration (molar) of free drug at which 1/2 amt of possible receptors are bound bound
Kd
Kd is _______ (directly or inversely) related to binding affinity
inversely
EC50 is generally ____ (lower, higher) than Kd
lower - b/c some spare receptors
____ is the maximum number of receptors that can be bound
Bmax
spare receptors occur when (2)
- drug dosent bind long but effect lasts (drug bouncing around to diff receptors)
- # of available receptors > # of effector molecules `
____ is the median effective dose - at which 50% of individuals exhibit the specific effect
ED50
____ is the median lethal dose - at which 50% of individuals exhibit a toxic effect
TD50
________ relates dose of a drug required to produce a desired effect to that which produced an undesired effect
Theraputic index
Theraputic index equation
TI = TD50/ED50
A safe drug has a ____ theraputic index b/c need a _____ dose for toxic effects and a ____ dose to be effective (high, low)
high; high; low
What are the 4 kinds of transmembrane receptors and how do they work
- transmembrane receptor protein - acts as an enzyme intracellular when ligand binds outside
- Transmembrane receptor bound to enzymatic protein (tyrosine kinase)
- ligand gated ion channel - open or closed w/ ligand binding
- Transmembrane receptor protein coupled with G protein - modulates second messenger production inside cell
How do lipid soluble ligands work?
cross membrane and act on intracellular receptor = stimulates gene transcription via binding to DNA sequences
ex. steroid hormones
steroid hormone (lipid soluble ligand) effects occur (when) ______ and last for ________
lag period (hours-days) ; hours-days
cytokine receptors are an example of ________
transmembrane protein receptors with intracellular enzymatic activity or stimulate protein tyrosine kinase
acetylcholine nicotonic receptor is an example of a ____________. Its effects take ________
ligand-gated transmembrane ion channel; milliseconds (instant)
the activated alpha unit in the GPCR ________ resulting in ________
exhanges bound GDP with GTP; dissociation of alpha subunit from beta-gamma dimer