Drug metabolism 2-mech Flashcards
what are phase II reactions?
-reactions that prepare activated compounds for excretion in the bile or urine
what enzyme is used for sulfate conjugation?
sulfotransferase
what is glutathione conjugation?
the conjugation of a tripeptide glutathione
what happens when the toxic electrohpiles and made from the metabolisim of drugs?
toxic electrophiles are made the tripeptide is conjugated with toxic electrophile which detoxify them and then excretion occurs
what is an overdose on paracetamol?
more than 10g/day causes fatal toxicity
what happens when conjugation depletes glutathione?
build up toxic metabolite> liver damage>death
what is codeine ?
its a prodrug of morphine
what is a single nucleotide polymorphism?
when a single nucleotide mistake occurs which could change the protein
what can polymorphism do?
- Can cause an increase in protein activity (extensive metabolisers)
- Can cause decreased/absent protein activity (poor metabolisers)
- Altered substrate specificity of enzyme
what converts codeine to morphine?
CYP2D6
what percentage of drugs does CYP3A4 metabolise?
50% polymorphism is rare unknown functional consequence
what percentage of drugs does CYP2C9 metabolise?
20% of drugs like NSAID, warfarin
what other uncontrollable facts affect drug metabolism?
- age very young and old
- disease can effect
- liver disease
