Lecture 2 Qs - Questions on Drug-Receptor Interactions

Question 1

Which of the following statements is most accurate?

a) A partial agonist will always have a higher efficacy than a full agonist
b) Agonists have higher affinities than antagonists
c) Full agonists that are selective for a given receptor will have the same efficacy
d) Antagonists possess better efficacy than their respective agonists
e) Competitive antagonists will preferentially occupy the relevant receptor in the presence of agonist

Answer 1

C) Full agonists that are selective for a given receptor will have the same efficacy

This is because full agonists are able to produce the maximal response in the tissue. If the full agonist is selective or non-selective, as long as they can both produce the maximal response, they will have the same efficacy.

Question 2

A drug acting as an inhibitor at a particular drug target site prevents the removal of neurotransmitter from the synapse. Which type of drug target is this drug acting on?

a) Receptor
b) Voltage-sensitive ion channel
c) Receptor-linked ion channel
d) Transport protein
e) Non-proteinaceous target

Answer 2

D) Transport protein

This is correct as it is transport of neurotransmitters that is being inhibited so a transport mechanism must be targeted. It can’t be a receptor as they aren’t directly involved in NT transport, both ion channels are involved in charged particle transport (i.e. ions) not NTs, and the four drug targets are all proteinaceous with the exception of steroidal receptors in the cell which aren’t involved in transport. Hence, the answer is D.