3 - Receptor pharmacology review

Question 1

Law of mass action

Answer 1

more drug added, the greater the response

Question 2

Affinity

Answer 2

forces of attraction between receptor and agonist (usually not covalent bonds because agonist can’t unbind from receptor)

Question 3

Potency

Answer 3

a drug is more potent than another if a lower concentration is required to achieve a response. (varies depending on the receptor)

Question 4

Histamine receptors

Answer 4

H1 and H2 (H1 sensitive to antihistamines)

Question 5

Efficacy (pharmacological)

Answer 5

ability of the agonist to produce a conformational change in the receptor. not linked to potency.

Question 6

Competitive antagonists

Answer 6

compete with agonist for same orthosteric binding site (active site)

Question 7

Allosteric modulator

Answer 7

binds to allosteric site, different to where agonist binds

Question 8

Inverse agonism

Answer 8

make receptors even less active than they are naturally (GCPRs have baseline level of activity all the time which inverse agonists would stop) e.g. cetirizine, loratadine etc.

Question 9

Clinical efficacy

Answer 9

ability of drug to provide a clinical effect in clinical trials.