Section 1 Flashcards
Pharmacodynamics
drug on the body
Pharmacokinetics
body on the drug
Tachyphylaxis
reduced effect of the drug over time after repeated administration of the same dose of a drug (effect)
Desensitization
reduced ability of a receptor to respond to stimulation by a drug or ligand (cause), like PKA, GRK (Arrestin), receptor internalization and can be homo or hetero
Inactivation
loss of ability of a receptor to respond to stimulation by a drug
Refractoriness
inability of receptor to respond to a drug for a period of time after the first drug-receptor interaction (example in the heart pumps)
Down-regulation
reduction in the number of receptors after chronic stimulation by agonists (lysosomal degredation)
Up-regulation
increase in the number of receptors after chronic inhibition by antagonists (Beta blockers)
An increase in Kd means what for affinity?
decrease in affinity
A decrease in EC50 means what for potency?
increase in potency
When you increase the concentration of agonist at Emax or greater what could happen?
toxic effects
What does Intrinsic Efficacy compare (hint- it’s on the dose response curve)
Emax
What is the Emax (Intrinsic activity) of a full agonist, a partial agonist, and an antagonist?
full agonist (a=1) partial agonist (0<a><1) agonist (a=0)
When EC50 < Kd for a full agonist, what does this mean?
spare receptors
Can a partial agonist have spare receptors?
no
How could a non-comp antag decrease potencyof a full agonist?
increase concentration of non-comp antag, but still having a small concentration, and the agonist has spare receptors
Does a non-comp antag effect efficacy or potency?
efficacy
Does a comp. antag effect efficacy or potency?
potency