Receptor theory

Question 1

Limitations of the law of mass action

Answer 1

• all ligands and receptors are equally available to each-other
• binding of drug and receptor is reversible
• binding of drug and receptor does not alter either the drug or receptor
• drug and receptor are either bound to eachother or not bound to each other

Question 2

operational model

Answer 2

• accounts for limitations in occupancy theory, these being receptors undergo conformational changes to alter their function (allosteric constant)

Question 3

Floor in the two state model

Answer 3

• Inverse agonist

Question 4

Clarks receptor occupancy theory

Answer 4

• OT is centred on the on the notion that if Ka = [drug concentration] required to occupy 50% of receptor sites at equilibrium , then the maximum response represents all receptors being occupied.

Question 5

Receptor reserve

Answer 5

• % of receptors not required for production of the maximal response
• allows signalling molecules to rapidly illicit a response