8/20/13 Flashcards
Too little drug, no effect
subeffective dose
Threshold effect and threshold dose
minimally effective dose
Graded response, increasing dose increases intensity of effect
dose dependent
Ceiling effect
maximally effective dose
Related to the size of the dose necessary to provide a certain effect, determined by the affinity of the receptor for the drug
Potency
Often used to measure drug potency
ED50
Related to the maximal effect obtained by the drug
Efficacy
Drug that binds to a receptor to produce a biologic response
Agonist
Drug that binds to a receptor and prevent the interaction of an agonist with the receptor
Antagonist
The magnitude of a pharmacologic response elicited by a drug which reversibly combines with its receptor is proportional to ____
the number or fraction of receptors occupied by the drug
Produces a ceiling effect that is not exceeded by other drugs
Full agonist
Full agonist and partial agonist differ in ____ but may or may not differ in _____
Efficacy, potency
Preference for inactive state
Inverse agonist
Difference between Inverse agonist and competitive antagonist
inverse agonist take receptor BELOW basal activity while competitive antagonist takes it to basal activity
Can potentiate effects of endogenous regulators
Allosteric activators
Antagonist has ____ for the receptor, but low to zero____
Affinity, efficacy
A competitive inhibitor will shift the dose-response curve to the
right
Compounds that bind to or inactivate an agonist before it can bind to its receptor
chemical antagonists
Noncompetitive antagonist always decreases the
maximal response (may or may not affect the potency of the agonist)
Physiological antagonists
Noncompetitive, blocks consequences of agonist binding to receptor
What can act like competitive antagonists at spare receptors?
Non-competitive antagonists
Spare receptors _____ the concentration of agonist required for full effect
decreases
Special class of proteins whose biological role is to receive signals from other cells or to sense the outside environment of cells
physiological receptors
extracellular signals that use physiological receptors
neurotransmitters, endocrine hormones, paracrine hormones, autocoids
single largest class of drug targets
physiological receptors
