Neuropharmacology Flashcards
Tom Ridler
What is the difference between an agonist and an antagonist drug?
Against activates receptor while antagonist binds without causing activation
Define efficacy
Once bound, how well drug elicits a response
Define affinity
how well drug binds to receptor
Define potency
amount of drug required to elicit response
What is the orthosteric site?
primary ligand site for a receptor
What is E50
The concentration of drug needs for half the maximal response
What is an inverse agonist
Decreases activation response
What is a neutral antagonist
Doesn’t produce response but blocks original affects
Compare irreversible and reversible antagonists
-Can unbind/can’t unbind
-Competes with agonists/changes rector share reducing its bind ability
In which direction would the sigmoidal curve go if there was negative affinity modulation?
To the right
What would happen to the curve of there was positive efficacy modulation
Go up and more right angle like
Describe the structure of a typical ligand receptor [2]
-heteromeric assemblies of 4-5 subunits
-each subunit has transmembrane spanning helices
Describe GPCR activation [3]
-binding of ligand induces GDP/GTP exchange on Ga subunit
-Ga dissociates from BY complex
-activated down stream targets e.g. cAMP, kinases
What are the 4 types of alpha subtypes in GPCR
Gas
Gai/o
Gaq
GBy
Describe what happens when kinase linked receptors are activated [4]
-dimerisation (bring closer together) of receptors
-Undergo autophosporylation at tyrosine residues
-Tyr recruits proteins with SH2 domains
-activation of downstream signalling