Formation and Secretion of Bile and Bilirubin Metabolism

Man produces 500–800 ml bile daily. Bile is produced by hepatocytes and is modifi ed in the biliary tree. We distinguish between the yellow-golden liver bile and the more yellow-brown gallbladder bile. The colour of the bile originates from bilirubin and bilirubin metabolites. Liverand gallbladder bile are isotonic because the tight junctions between bile duct epithelial cells are freely permeable to water. Bile is a micelle and lipid rich watery fl uid. In contrast, the so called “chalk-milk bile” is pasteous and partly crumbly. In gallbladder hydrops, gallbladder bile is a watery clear fl uid. This means that bile may change its consistency from a watery fl uid to a solid mass. Cholesterol, phospholipids, bilirubin, electrolytes, proteins and several drugs are excreted with the bile.