Liver Biochemistry Flashcards
(24 cards)
Cell in the space of disse that stores vitamin A
Stellate, also store lipids
lose vit a stores when activated
Cells that are natural killers in space of disse to protect against viruses
Pit cells
Chemical reactions in Phase 1 of detoxification of xenobiotics
reduction, oxidation, hydroxylation, hydrolysis
this increases solubility and gets active sites for adding something else (phase 2)
Chemical reactions in Phase 2 of detoxification
Conjugation, sufation, methylation, gluconuration. increases solubility
cytochome p450 use what cofactors to do shit
NADPH and O2
What makes the p450 enzymes be expressed?
their substrates
What would cause vinyl chloride to cause angiosarcoma?
the CYP2E1 or Glutathione cannot keep up with the amount of exposure.
(phase 2 reactions can’t keep up)
what give the sulfur in phase II reactions?
PAPS
phosphoadenosine phosphosulfate
Why shouldn’t I butt chug a four loko and eat an acetomenophen sandwich?
Ethanol induces expression of CYP2E1, which metabolizes acetominophen to NAPQI, which is toxic.
What’s the mechanism of ethanol toxicity?
acetaldehyde activates the Kupffer cells. They secrete TGF-Beta that turns the stellate cells into collagen forming cells –> fibrosis.
what enzyme take NH4 off of glutamine when it gets to the liver
Glutaminase
After glutaminase, what happens to NH4?
Carbamoyl Phosphate synthase 1 (CPS1) –> Carbamoyl Phosphate –> then ornithine
What if CSP1 is saturated and can’t fix ammonia anymore?
We put the ammonia back onto glutamine so it’s not just floating around
What happens to beta-cat if WNT isn’t around?
It gets phosphorylated by APC and degraded in the proteosome
Why is there a high WNT expression near the central vein in a liver lobule?
WNT causes glutamine synthase to be made. So far away from the center, free ammonia can be used in the urea cycle
Ketones are made from what?
Fatty acids –> acetyl CoA –> acetoacetate –> beta- hydroxybutyrate
What are the products of the pentose phosphate pathways used for?
NADPH –> cholesterol synthesis, also detox of xenobiotics (cyto 450)
Ribose –> nucleotide synthesis
Sugars are attached to what molecule to make glycoproiens? What is it made of?
btw, this happens in the ER of hepatocytes
Dilochol
from cholesterol
what enzyme is elevated in bile duct blockage?
alkaline phosphatase
Deceased Albumin can be caused by acute or chronic liver failure?
Chronic, because it has a long half life
Why can a long PTT be from liver damage
bc that’s where the clotting factors are made you dummy!
Grapefruit juice inhibits what enzyme.
What drug does that normally metabolize
Cyp3A4
statins
Phosphoglucomutase 1 catalyzes what reaction?
if you have a mutation in it, what symptom is present
Glucose 1-P to glucose 6-p
goes bothdirrections depending on [ ]’s
resting hypoglycemia
What amino acids help get rid of Nitrogen?
Alanine - from other AA’s
Glutamine - can fix free ammonium
