Lecture 4 Drug receptor theory (agonists) Flashcards
what is EC50
this is the concentration of the drug at 50% of maximal response
on a concentration response curve, where is EC50 in relation to KD
EC50 is shifted to the left of KD (affinity)
how does amplification of signalling effect drug response
means that 100% occupancy is not necessary for a response of the tissue.
what does efficacy influence?
how big or how well the tissue produces a response.
what is the Hill equation?
response=max.[Xa]n/([Xa]n+[EC50]n).
Xa is concentration of agonist.
N is slope factor
what does the Hill slope represent?
related to measure number of molecules that binds to a receptor to activate it.
How does potency effect EC50
Drug with highest potency requires a lower concentration for EC50
what does EC50 depend on?
affinity and efficacy
efficacy of a partial agonist
partial agonists have a lower efficacy compared to full agonist. Partial agonists need 100% occupancy to produce max response
What do inverse agonists do?
stabilise the resting state of the receptor.
properties that determine the effect of a drug in a living system
- specificity
- affinity
- efficacy of agonists
how to measure relative potencies
comparing doses of the same amount of standard and unknown
