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Flashcards in GNG Deck (6)
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1
Q

LDH-5

A

Cori cycle; lactate oxidized to pyruvate; NAD+ required as cofactor

2
Q

Main substrates for GNG

A
  1. Lactate from anaerobic glycolysis
  2. Glucogenic a.a. (alanine & glutamate) from muscle protein breakdown
  3. Glycerol derived from TAG lipolysis
3
Q

Irreversible steps in GNG (4)

A
  1. Pyruvate carboxylase (mitochondrial matrix); requires Biotin (ABC)
  2. PEP-carboxykinase (cytosolic); requires GTP
  3. F1,6-Bisphosphatase (cytosolic)
  4. G6-Phosphatase (cytosolic)
4
Q

Hepatic Glyercol Kinase fx?

A
  • phosphorylates glycerol producing Glycerol-3-P
  • Glycerol-3-P converted to DHAP
  • No net production of glucose from the carbons of
    acetyl CoA or of fatty acids
5
Q

Role of Fructose 2,6 bisphosphate in GNG?

A

Decreased levels of F2,6-Bisphosphate decreases inhibition inhibition of FBP-1, which leads to increased rate of GNG

  • Glucagon ->->->PKA-> phosphorylated PFK-2/FBP-2 (bifunctional) complex
  • phosphorylated PFK-2 (INactive)/phosphorylated FBP (Active) impeding formation of F2,6-bisphosphate
6
Q

Glucose-6-Phosphatase fx?

A

In order for export of glucose to blood to occur, phosphate must be removed from G6P by glucose-6-phosphatase