PD

Question 1

Define the terms affinity, efficacy, potency and specificity

Answer 1

Affinity —> tendency to bind to receptor.
Efficacy —> ability of a drug to produce a biological response.
Potency —> how much of a drug is required to produce a response.
Specificity —> a drug must act selectively and show binding site specificity.

Question 2

Define reversible and irreversible antagonism

Answer 2

Reversible —> reversible binding = inhibition, increased conc. Of endogenous ligand required to activate.
Irreversible —> slow/non present dissociation. Replacement of receptors required for activation.

Question 3

How is tachyphylaxis achieved (6).

Answer 3

Change/translocation of receptors, exhaustion of mediators, increased metabolism, extrusion, physiological adaptation.

Question 4

4 major types of drug targets

Answer 4

Receptors, ion channels, enzymes, transport/carrier proteins.

Question 5

4 main types of receptor proteins

Answer 5

Ligand gated, kinase-linked, G-protein coupled, nuclear receptors.