P450 Flashcards
overview of the lecture
- different CYPs involved in drug metabolism
- mech of CYP action
- effects of mutations and polymorphisms in CYPs on drug metabolism
what are the major characteristics of cytochrome?
- perfrom RedOx rxn (phase 1)
- bound to the lipid membranes of the smooth endoplasmic reticulum
- most are found in the liver, but exist in lung, kidney, heart, and brain also
CYP enzymes are an important biotransforming system,
utilizing mostly oxidation and reduction
what is a prodrug?
a medication that is administered in an inactive or less than fully active form, and is then converted to its active from through a normal metabolic process.
what is an example of prodrug?
codeine (inactive) becomes morphine via CYP2D6.
codeine is a prodrug that is metabolized by CYP2D6, when Rifampin was given what happens?
Rifampin induce CYP2D6, thus converts more codeine to morphine
Define prodrug
a medication that is administered in an inactive or less than fully active form, and is then converted to its active form through a normal metabolic process
Define induction
biotransformation by induced CYP enzmyes results in either increased activity of prodrugs or enhanced elimination of drugs
what is it called that a genetic change that exists for at least 1% of population?
polymorphism
when does CYP polymorphism occur?
when the biotransforming properties of an enzyme are altered
warfarin is taken for
artrial fibrilation
warfarin is used to inhibit
factors 2, 7, 9, and 10, thus anticoagulating the blood
warfarin is measured in
INR
what are the substrates for CYP2C9?
Warfarin, Phenytoin
warfarin is a substrate for CYP2C9 and is
metabolized at a satisfactory rate for the patient’s blood to be adequately anticoagulated
