Cv: To explain the law of mass action + describe affinity & dissociation constants
LAW OF MASS ACTION states that the rate of a reaction is dependent on the [ ] of reagents
Binding of ligand with receptor:
KD = dissociation constant = [ ] when 50% of receptors is occupied
IF KD = low number → indicates less drug is required to occupy 50% receptors, implying each molecule is tightly associated with its receptor
KA = association constant (reciprocal)
- Measures the affinity of drug for receptor
- When plotted on logarithmic scale
- Receptor occupancy v. drug concentration
- Relationship represents sigmoid curve