Hepatobiliary system

This refers to the liver, gall bladder and bile ducts, and how they work together to make bile. Bile consists of water, electrolytes, bile acids, cholesterol, phospholipids and conjugated bilirubin. Some components are synthesised by liver cells, the rest are extracted from the blood by the liver.

Bile is then secreted by the liver into small ducts that join to form the common hepatic duct. Between meals, secreted bile is stored in the gall bladder, where 80%-90% of the water and electrolytes can be absorbed, leaving the bile acids and cholesterol. During a meal, the smooth muscles in the gallbladder wall contract, leading to the bile being secreted into the duodenum.

To see how this relates to the metabolism of bile, read bilirubin metabolism.