Liver Biochemistry Flashcards
Pit cells of liver
resident lymphocytes
Phase I reactions
Phase II reactions
I: add –OH group, makes reactive and more soluble
II: add substitute groups onto –OH groups, increase excretion of products
Acetaminophen toxicity: story
many different formulations all containing acetaminophen
taken without considering that
EtOH effect on acetaminophen metabolism
EtOH increases expression of CYP2E1
CYP2E1 metabolizes acetaminophen to NAPQI (toxic)
CYP2E1
expression upregulated with EtOH makes NAPQI (toxic byproduct)
NAPQI
acetaminophen metabolite (toxic)
enzyme: CYP2E1
enzyme upregulated by EtOH
How does EtOH cause liver fibrosis
acetaldehyde activates Kuppfer cells
Kuppfer cells activate stellate cells to lay down collagen
fibrosis of liver
Phosphoglucomutase-1 function
interconverts G1P and G6P
de novo synthesis of cholesterol from
carbohydrates
Two aa that carry nitrogen in blood
alanine: only N from other compounds
glutamine: can fix free ammonia
Glutaminase and glutamine synthase in hepatocytes
glutaminase: at portal canal
glutamine synthase: at central vein
Glutamine synthase expression in hepatocyte
Wnt regulated Wnt secreted by cells around central vein binds Frizzled receptor inactivates kinase of β-catenin β-catenin goes to nucleus transcription of glutamine synthase
Gluconeogenesis and urea cycle
gluconeogenesis from aa
nitrogen needs to be removed from the aa
so dependent on urea cycle
Nucleotide components derivations
sugar component: glucose
base component: amino acid
Dolichol
base for glycoproteins
base for branching of glycoproteins
