Lect 3 - Molecular aspects of drug action Flashcards
what are the different targets of drugs you don't need to know structures also don't need mechanism in these lectures
what are the main targets of drugs
receptors ion channels enzymes transporters exceptions
q
agonist keeps receptor in active state
antagonist inhibits agonist
understand how drugs work on different things
ion channel
enzyme
transporter
receptor (in another lecture)
what is a pro drug
need to be metabolised before it can affect the target
what are some exceptions to the above in terms of how drugs work
- microtubule inhibitor
- DNA modifiers
- osmotic diuretics
- antacid
how do drug work on ion channels
drugs that target ion channels work by blocking the channel.
e.g. amiloride is a weak diuretic (promotes urine production) that blocks Na channels
how do drugs work on enzymes
drugs can target enzymes in 3 ways
- acting as an inhibitor by blocking the activation site
- acting as false substrate so that abnormal metabolites are produced
- pro-drug aka precursor to drug which then becomes fully active after being processed the enzyme
why might we use prodrug
a prodrug might be used to improve how a medicine is absorbed, distributed, metabolized, and excreted (ADME).
Prodrugs are often designed to improve bioavailability when a drug itself is poorly absorbed from the gastrointestinal tract.
what is an example of a drug that works on enzymes, how does it work
Allopurinol - reduce inflammation in gut
does so by inhibiting Xanthine oxidase
how do drugs that target transporters work
transporter drugs work by either blocking (inhibiting) the transporter from working, or by being false substrate leading to abnormal metabolite
why are proton pump inhibitors pro-drugs
proton pump inhibitors are pro-drugs because pump inhibitors need to be metabolise before they will act
what are the 4 exceptions to how drugs act
- microtubule
- DNA
- osmotic diuretics
- antacids
