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Ethanol metabolism
 - NAD+ = limiting reagent
- Alcohol dehydrogenase operates via zero-order kinetics
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What is ethanol hypoglycemia
- Elevated NADH/NAD+ ratio ->
- pyruvate -> lactate
- oxaloacetate -> malate
Which stimulates fatty acid synthesis and inhibits gluconeogenesis
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Rate determining enzyme for
De novo pyrimidine synthesis
Carbamoyl phosphate synthetase II
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Rate determining enzyme for TCA cycle
Isocitrate dehydrogenase
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Glucokinase
Liver and B cells of pancreas
- Low affinity(high Km)
- High capacity (high Vmax)
- induced by insulin
Glucose -> Glucose-6-phosphate
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Enzyme and regulators for
Fructose-6-P to Fructose-1,6,BP
Phosphofructokinase-1
- Positive
- - AMP
- - fructose-2,6,BP (forced induction)
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Pyruvate dehydrogenase complex
Pyruvate -> acetyl-CoA
- Cofactors
- Pyrophosphate (B1, thiamine)
- FAD (B2, riboflavin)
- NAD (B3 niacin)
- CoA (B5 pantothenate)
- Lipoic acid
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Pyruvate dehydrogenase deficiency
Backup of pyruvate and alanine -> lactic acidosis
CLINICAL: neurologic defects
- Treatment:
- increase ketogenic nutrients (high fat content or increase lysine and leucine)
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Rotenone
CN-
antimycin A
CO
Electron transport inhibitors
Decrease in proton gradient and block of ATP synthesis
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