Liver Fucntion (physiology) Flashcards
What are the hepatic functions of the liver ?
Immune defense
Metabolism
Production of important molecules
Storage
Bile production
What do the enzymes in hepatocytes do ? (Metabolism)
Blood glucose control
Protein metabolism
Lipid metabolism
Heam metabolism
Detoxification and activation.
What’s immunity ?
(Kupfer cells) prevent pathogens entering systemic circulation from hepatic portal vein.
Also recycles erythrocytes.
What the metabolism?
Glucose, lipids, proteins, heme
What’s the production of important molecules?
Albumin clotting factors.
CPR.
Transport molecules.
What’s does it store?
Glycogenesis
Lipogenesis.
Vitamin ADEK
Vitamin B12
Iron
What are the macrophages in the liver called?
Kupfer cells
What does the bile consist of?
Water and ions
Bilirubin (gives color)
Bile salts (emulsify fat globules into smaller fat droplets fro easier digestion and absorption).
Phospholipids
Cholesterol
Other like hormones.
Why is bile needed?
Needed to make lipids Easily digestible and absorbable in the GIT and to neutralize (alkalinise) stomach acid.
What does emulsification entail in the GIT?
The break down of large fat globules into smaller fat droplets ( increase surface area area) using emphiphilic (molecules with a hydrophobic and hydropilic end)
Molecules which form micelles around fat to make them more easily digestible and absorbable (bile salts).
What metabolic function does the liver have in relation to glucose ?
Blood glucose control-
Alter enzymes activate in response to hyperglycemia (high glucose) to cause glycogensis ( conversion of glucose to glycogen.
Fatty acid biosynthesis (glucose as substrate).
Hypoglycemia response -
Glucose genesis (makes glucose from a glycerol and lactate).
Glycogenolysis (catabolism of glycogen into glucose).
What function does the liver have in relation to protein?
Catabolism of GIT peptides and degradation of peptide hormones, steroid hormones and drugs.( may activate or deactivate).
Deamintion ( for energy or before converting into glucose / fats) by product is ammonia.
Urea cycle to convert and excrete highly toxic ammonia as harmless area.
Transamination (AAs converted to keto acids to use in Krebs cycle or to generate glutamate - important for ammonia metabolism.
What’s protein synthesis?
Albumin -for water balance , important for oncotic/ colloid pressure in plasma.
C-reactive protein (CRP) inflammatory maker.
Clotting factors.
Transport proteins like albumin, globulins, lipoproteins and transferrin (bind and transport iron).
What metabolic functions does the liver have in relation to lipids?
Lipids:
Storage (vitamins A,D,EK and B12).
Processes lipids:
Send lipids to adipose tissue and arteries.
De novo lipogensis (converts excess glucose to fatty acids).
Receives lipids from adipose tissue and arteries.
Uses free fatty acids for energy, hormones and phospholipids.
Also add lipids to biliary secretions (cholesterol and phospholipids)
