Functional Protein receptors:
Fluoxetine on serotonin tpt
Penicillin on transpeptidase in bacterial
cell wall synthesis
Antacids
Al/Mg hydroxide
Nucleic acid receptors:
Actinomycin D on DNA
Streptomycin on RNA
Bulk laxatives
agar/methyl cellulose
Osmotic diuretics
mannitol
D binds R
Receptor
theory
Not all drugs need receptors
Receptor: any component of
a biological system that
interacts with a drug, leading
to the drug effect
Agonist
Interacts w/ receptor
elicits direct response
Antagonist
interacts with receptor
no direct response
affinity (Kd)
Principles of Drug Action
DR complex
efficacy
chemical antagonism
potency (EC50)
dose required to
procduce a given
degree of response
slide 13, 14, 15
efficacy
affinity
measure of biological
effectiveness of DR
complex
P(drug molecule
interacts with its
receptor to form DR
complex)
lower EC50 = higher
potency
slide 12
slide 10
Effector
(activated by DR complex)
Response =
elicited because receptor
occupied
- more DR complex, more
response
chemical antagonism
(drug level)
physiological antagonism
pharmacological
antagonism
(receptor level)
antagonist binds to R,
prevents active drug
from binding
-C or NC antagonism
no pharmacological
efficacy but may have
clinical efficacy
(therapeutic)