Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
39 Cards in this Set
- Front
- Back
|
What are the four types of transduction mechanisms?
|
1) G-protein
2) Ion channels 3) receptors as enzymes 4) receptors regulating nuclear transcription |
|
|
What is a drug's response determined by?
|
affinity for receptor and the efficacy of the drug-receptor complex to produce a response
|
|
|
Competitive antagonist
|
reversible
shift to right slope does not change affinity is reduced |
|
|
Noncompetative antagonist
|
not reversible
max is reduced slope is reduced affinity does not change apparent # of receptors is decreased |
|
|
partial agonist
|
may act like an antagonist in the presence of a full agonist
|
|
|
Two state model
|
-receptor is active or inactive
-inverse agonist makes it inactive producing an opposite effect -antagonist does not alter the equilibrium, no preference for active or inactive form |
|
|
Quantal Dose Effect
|
-responses are all or nothing
-a frequency distribution of the response of population of a drug at increasing concentrations |
|
|
Hyperreactive
|
respond to doses below the ED50
|
|
|
Hyporeactive
|
respond to doses above the ED50
|
|
|
Tachyphylaxis
|
rapidly induced tolerance only after a few doses
|
|
|
Therapeutic Index
|
LD50/ED50
|
|
|
Certain Safety Factor
|
LD1/ED99
|
|
|
Factors controlling the minimum effective concetration (MEC)
|
absorption, distribution, biotransformation, excretion
|
|
|
Fick Equation
|
DAK(Co-Ci)/X
|
|
|
Ion trapping
|
weak acids will be on the side of the membrane with a higher pH, and weak bases will be on the side of the lower pH.
|
|
|
What is the difference between passive and facilitated diffusion?
|
both are down a concentration gradient but facilitated requires carriers
|
|
|
ABC super family
|
7 families
active transporters, usually out p-glycoprotein - over expression may confer resistance to chemotherapy |
|
|
SLC super family
|
43 families
facilitated and active, in and out serotonin and dopamine receptors |
|
|
enteral administration
|
oral
sublingual (tongue) rectal |
|
|
parenteral routes
|
IV
IM subcutaneous (fat or skin) topical inhalation |
|
|
Where are the highest perfusion rates?
Intermediate? Slowest? |
highest - kidney, liver, lung, brain
intermediate - muscle slow - fat and bone |
|
|
How does a drug bound to a plasma protein affect distribution?
|
-can't pass membrane, lowers free concentration
-can't be filtered by kidney -albumin is the most important plasma protein for acidic drugs |
|
|
What types of drugs is redistribution applicable to?
|
those with high lipid solubility, CNS or cardiovascular
|
|
|
What are the two phases of redistribution?
|
1) flow dependent - going to tissues with larger flows first
2) then it goes to those with low flow |
|
|
What is the equation for renal clearance?
|
(conc. of drug in urine) * (vol of urine formed/hr) / (conc. of drug in plasma) = clearance
|
|
|
4 types of excretion?
|
renal, bile, respiratory, others (sweat, tears, saliva, milk)
|
|
|
How does the liver secrete drugs?
|
-they secrete them into bile involving p-glycoprotein or other ABC protein.
-may be reabsorbed, enterhepatic circulation |
|
|
What does biotransformation typically do to a drug?
|
It makes it more polar
|
|
|
What are the phase 1 and phase 2 biotransformation reactions?
|
1) adding a functional groups for phase 2, usually more polar and oxidation
2) large molecule, glucuronidation, more water soluble, inactivation |
|
|
What part of the cell contains cyt P450?
|
smooth ER
|
|
|
what are two non-microsomal drug oxidations?
|
alcohol and aldehyde dehydrogenase
monoamine oxidase |
|
|
zero order kinetics
|
rate is independent of concentration
|
|
|
first order kinetics
|
rate is proportional to concentration
|
|
|
What is the slope equation for first order elimination kinetics?
|
slope = -ke/2.3 (1/time) ke = elim rate
also... vol distributed = X (mass) / Co |
|
|
What is the half life equation?
|
t(1/2) = 0.693/ke= 0.693 (Vd/ke)
|
|
|
What is the whole body clearance?
|
Cl = ke*(Vd)
|
|
|
What happens when the dosing intervals are less frequent than t1/2 or more frequent than t1/2?
|
less: large fluctuations
more: small fluctuations |
|
|
The dose of a drug that will produce the desired therapeutic level at a steady state.
|
maintenance dose - it is equal to the amount of drug to replace what was lost at the previous interval
|
|
|
What is the equatoin for maintenance dose?
|
dosing rate x dosing interval
|
