Week 1

Question 1

List the key biological drug targets (associated with respiratory system)

Answer 1

Drug Targets:
1. Enzymes
2. Receptors (on cell membranes OR intracellular i.e nuclear, cytoplasmic)

Question 2

What is the mechanism of beta agonists?

Answer 2

Agonist - activate / trigger a response

Full agonist = full response
Partial agonist = partial response (NOT full)
Biased agonist =activates a group of receptor’s signalling cascade
Inverse agonist = produces opposite effect of natural ligand

Beta agonist (e.g. beta-adrenoreceptor) activates adenyl cyclase = increased production of cAMP
cAMP activates protein kinase A = protein phosphorylation + change in Ca2+ conc.
Causes biological response

Question 3

What is the mechanism of inhaled corticosteroids?

Answer 3

Drug binds to receptor = hormone-receptor complex is formed
Complex enters nucleus + binds to receptor site on chromatin
Binding causes increase protein transcription

Drug: corticosteroid, hormones

Question 4

What is the mechanism of muscarinic agents?

Answer 4

M2 and M4 receptors inhibit adenyl cyclase = decrease intracellular conc. of cAMP
M1, M3, and M5 receptors activate phospholipase C
1. causes change in Ca2+ conc. = biological response
2. activates protein kinase C = protein phosphorylation = biological response

Question 5

What is the mechanism of leukotriene antagonists?

Answer 5

Antagonist - prevents agonist from binding to receptor

Competitive antagonist - binds to same site (as agonist)
Non-competitive - bins to different site

Reversible antagonist - short lived bonds (dissociate easily)
Irreversible antagonist - strong covalent bonds (doesn’t dissociate)

Question 6

Toxicities of key drugs used to treat infection & respiratory disease

Answer 6

Lower drug conc. required to produce effect = high potency
Higher drug conc. required to produce effect = low potency

High doses (above therapeutic window) causes toxicity

Question 7

How does a drug produce an effect?

Answer 7

Drug binds to a target (tight binds) forming a target-drug complex
This complex produces a response

Target usually on cell membrane, can be intracellular
If drug size, shape etc. is correct = higher affinity between target + drug