essential pharmacology Flashcards
what is a drug
a chemical agent that affects a biological system
what is meant by a receptor ?
is a binding site a drug interacts with to get into action
what does adding a small amount,large amount and maximum amount of ligand do in terms of drug- receptor interactions
small amount of ligand = small response
large amount of ligand = large response
maximum amount of ligand = maximum response
what does a higher E50 value and lower E50 indicate in terms of affinity ?
higher E50 means lower affinity
lower E50 indicates higher affinity
if affinity is high or low what direction does the graft shift to?
high affinity = left shift on x-axis
low affinity = right shift on x-axis
is E50 directly proportional or inversely proportional to the affinity between a receptor and a drug
it is inversely proportional (lower E50 means higher affinity )
how is the efficacy determined ?
how good the drug is at activating the receptor
what is meant by endogenous agents
made by the body e.g hormones , neurotransmitters
give example of exogenous
drugs
what is signal transduction ?
turning a chemical signal into an appropriate response
what is an agonist and antagonists ?
agonist ; mimics normal action of receptor
antagonist ; blocks the normal action of receptor
explain the coupling of G proteins to adenylyl cyclase
produces cAMP as 2nd messenger
cAMP regulates protein kinase A which the phoshorylates a protein and produces a cellular response
what is the biggest class of cell surface receptors?
G-protein receptors
explain the coupling of G protien to phospholipase
produces DAG and IP3 as 2nd messengers
this regulates PKC
which phosphorylates a protein and produces a response
what are properties of a full agonist ?
high affinity high efficacy
