Liver energy metabolism:

• production ATP by
  • Oxygen from hepatic artery + portal vein.
  • Basic units: carbs, fats, proteins

Carbohydrate metabolism

• amylases break down carbohydrates into mono, di and polysaccharides.
• Uptake in the liver through GLUT2 (birectional)
  • directly used for energy
  • stored as glycogen in liver + muscle (approx 120 g of glycogen max)
  • converted to fat/amino acids (extreme)

Protein metabolism

• breakdown by pepsin, trypsin, chymotrypsin into aminoacids.
• cannot be stored, but are toxic → urea cycle
• amino acids can be metabolized to glycogen or fat
• proteins can be used to sustain metabolism in extreme starvation

Fat metabolism

• emulition by bile acids
• breakdown of triglycerides → glycerol and FFA (lipolysis) in the intestine by pancreatic lipase.
• long vs short
  • 5-12C: directly released intro the portal vein, bound to albumin
  • 13-21C: reformed into triglyceride, coated with cholesterol → from chilomicrons that are released in the lymphatic system and eventually bloodstream.
• can be taken up in the liver
  • oxidized by energy (beta-oxidation)
  • stored
  • very low density lipoproteins (VLDL) binding for transportation to other tissues?

Phases of metabolism

1. prospranial 1-2 hours after meal