Exam 1 - 1st half Flashcards
Pharmacokinetics
what the body does to the drug
absorption, distribution, metabolism, excretion
Pharmacodynamics
what the drug does to the body
Properties of drugs
drug size
shape (stereochemistry)
reactivity
hydrophobicity
greater hydrophobicity means ____ ability to cross biological membranes
greater
4 types of drug-receptor interactions
- g protein couple receptors (main one)
- ion channels
- transmembrane with cytosolic domains
- intracellular receptors
g- protein coupled receptors act in ____ time
seconds to minutes
examples of second messengers (2 of them)
cAMP
Ca2+ phosphoionisitide signaling
ion channels act in ___ times
miliseconds (QUICK)
3 KINDS of ion channels
ligand gated
voltage gated
second-messanger regulated
ligand gated channels transmit signal across plasma membrane by _______ transmembrane conductance and changing ____ potential
ligand gated channels transmit signal across plasma membrane by increasing transmembrane conductance and changing membrane potential
example of ligand-gated channels
nicotinic ACh receptor
transmembrane receptors with cytosolic enzymatic domains (5 kinds)
- receptor tyrosine kinase (insulin)
- receptor tyrosine phosphatases (immunosuppression)
- tyrosine kinase -associated
- Ser/Thr kinases (cell growth)
- guanylyl cyclases (smallest family)
intracellular receptors (3 kinds)
- enzymes
- transcription factors
- structural proteins
actions of drugs NOT mediated by receptors (3 kinds)
- antiacids
- agents that affect osmolarity
- chelatic agents
greater potency the drug means the concentration needed for the response is
smaller
what value does potency get associated with?
EC50
the lower the EC50 the _____ the drug
more potent
the higher the EC50 the ____ the drug
less potent
Emax is known as
the maximum response
partial agonists are ____ potent than standard agonsits
LESS
antagonist is an agent that binds to a receptor but cannot produce the conformational change necessary to
trigger the downstream events
competitive antagonists bind ____ to the receptor
REVERSIBLY
With competitive antagonism what kind of shift in the curve do you see?
a shift to the right
in competitive antagonist explain what happens to efficacy and potency
efficacy stays the same, potency goes DOWN
non-competitive antagonists ____ the receptor, its a ____ action
non-competitive antagonists inactivates the receptor, its a non-reversible action
in non-competitive antagonist explain what happens to efficacy and potency
potency stays the same and efficacy goes down
physiological antagonism
agonist and antagonist acting at 2 independent sites, opposite effects
chemical antagonism is caused by combination of
agonist with antagonist with resulting in inactivation of the agonist
what are the advantages to the spar receptors
activation at low concentrations with faster turn of
what is the most common mechanism that drugs pass membranes?
passive diffusion
acidic drugs are better absorbed in the
stomach
acids with accumulate in
basic compartments
bases are absorbed in the
small intestine
bases will accumulate in
acidic compartments
bioavailability is the measure of the _____ of the orally administered drug that _____ systemic circulation
bioavailability is the measure of the percent of the orally administered drug that enters systemic circulation
volume of distribution is related the blood _____ to the
blood concentration to the amount in the body
what 2 properties determine Vd value
lipid solubility and binding to plasma proteins
high lipid solubility means plasma concentration is low so the Vd is
a large value
binding to plasma proteins typically results in a what Vd value?
a lower value
what organ is the most important for excretion?
the kidney
in renal golmerular filtration what drug is filtered?
only the unbound drug
renal tubular secretion can be inhibited by what drug?
probenecid
renal tubular reabsorption is influcened by what properties?
nonionized, lipid solubility
adding sodium bicarbonate will allow trapping of what kind of drug in the urine ?
acidic drugs
adding ammonium chloride will allow trapping of what kind of drug in the urine?
basic drugs
phase 1 metabolism refers to what reactions?
oxidation, reduction, hydrolysis
phase II metabolism referes to what?
functional groups being attached to the drug molecule
zero order is constant ____ lost per unit time
constant amount lost per unit time
first order is constant ___ is lost per unit time
constant fraction or % lost per unit time
what is a good example of zero order
alcohol
half life can only be determined for
1st order kinetics
as 1/2 life increases what decreases?
ke (elimiation constant )
the elimiation rate constant gives a measure of the
rapidity of the drug elimination
steady state is when
rate of input and rate of ouptu per day are equal
elimination kinetics control ____ kinetics
accumultion kinetics
clearance is only for ____ order kinetics
1st order
bioavailability is also known as the
area under the curve
therapeutic index is an estimate of the ____ of the dose needed to produce ___ response from the dose that produces _____
therapeutic index is an estimate of the separation of the dose needed to produce desired response from the dose that produces toxicity
problems with TI (4)
- data must be collected in animals
- applicability of animal data to humans is uncertain
- ED50 is not a realistic dose, ED99 would be better
- assumption is that ED and LD curves are parallel and this isn’t always the case