Liver Structure and Function - Flash Card
Hepatobiliary system - refers to the liver, gall bladder & bile ducts
liver comprises several lobes
receives blood from the hepatic artery (25%) & the hepatic portal vein (75%)
blood from spleen and GI tract passes through liver
largest internal organ (~1.5kg)
Tissue contains two major cell types: parenchymal and non-parenchymal
parenchyma (aka hepatocytes): accounts for 80% of liver volume, 60% of cells
hepatocytes in outer areas of lobule are specialised for oxidative functions - well perfused - such as gluconeogenesis and cholesterol synthesis
cells in the inner zone are more important for glycolysis, lipogenesis and cytochrome P-450 based drug detoxification
cells in the inner areas are less well perfused and more susceptible to ischaemic injury
hepatic portal vein = poorly oxygenated, high in nutrients
hepatic artery = highly oxygenated, low nutrients
The non parenchymal cells of the liver include populations of cholangiocytes (epithelial cells), sinusoidal endothelial cells, stellate cells, Kupffer cells, and intrahepatic lymphocytes.
Functions including:
detoxification - particularly nitrogenous compounds, hormones & drugs
synthesis
metabolism
storage - glycogen, iron, copper, and fat soluble vitamins
breakdown
bile production
Carbohydrate
storage of glycogen
main source of blood glucose
Fat
dietary fat processing
lipoprotein synthesis
Protein
major site of protein synthesis, especially plasma proteins e.g. albumen, coagulation factors
protein catabolism and urea production
