Drug Metabolism by the liver Flashcards
What is the first metabolism route?
Oral Medication Intestinal Tract Portal Vein LIVER Hepatic Vein Hepatic Artery LIVER *Goes to other places in the body*
What is the purpose of drug metabolism?
Makes drugs MORE polar.
Increases solubility in urine and thus, can be excreted.
What is phase 1 in metabolic reactions?
Involves breaking down substances (KNOWN AS CATABOLIC).
Makes drug MORE REACTIVE and therefore, it can be MORE soluble.
What is phase 2 in metabolic reactions?
Makes the drug MORE SOLUBLE in water -> therefore, it is MORE polar.
What is phase 2 known as in metabolic reactions?
Glucuronidation.
What are microsomal mixed function oxidases?
Important group of enzymes involved in Phase 1 metabolism.
What does microsomal mixed function oxidases require?
Requires oxidase substrate, NADH, NADH - P450 reductase and molecular oxygen.
Where are microsomal mixed function oxidases found?
Embedded in lipid membranes.
What is known as a catalytic centre?
Haem group.
What is the purpose of a harm group?
Enables the substrate to bind to the active site.
What is the purpose of the cytochrome P450 cycle?
Allows the recycling of cytochrome P450 and the generation of an oxidised derivative of the drug.
Name the steps in the cytochrome P450 cycle.
At the start = p450 is binded to iron.
Drug complex is formed as fe3+ DH.
Fe03+ = oxidized version of the drug.
Cytochromee p450 is recycled and then the cycle starts again.
OXIDATION OF THE DRUG = CYTOCHROME P450 CYCLE.
What can affect the activity of the enzyme?
Ability to be induced.
What effect does clopidogrel have?
Has an active metabolite produced by the action of CYP22C19.
What effect does omeprazole have?
Proton pump inhibitor used for the treatment of gastric ulcers.
INHIBITOR OF CYP22CQ9
