has output bile acid secretion Bile contains bile acids, glutathione, phospholipids, cholesterol, bilirubin, and other organic anions, proteins, metals, ions, and xenobiotics. Hepatocytes begins the formation of bile by transporting bile acids, glutathione, and other solutes including Xenobiotics and their metabolites into the canalicular lumen. The major driving force of bile formation is the active transport of bile salts and other osmolytes into the canalicular lumen. Most conjugated bile acids (taurine and glycine conjugates) and some unconjugated bile acids are transported into hepatocytes by sodium-dependent transporters. Sodium-independent uptake of conjugated and unconjugated bile acids is performed by members of the organic anion-transporting polypeptides (OATPs). OATPs also transport numerous drugs and hepatotoxicants. Lipophilic cationic drugs, estrogens, and lipids are exported by the canalicular multiple-drug resistance (MDR) P-glycoproteins, one of which is exclusive for phospholipids. Conjugates of glutathione, glucuronide, and sulfate are exported by multidrug resistance-associated protein2 (MRP2). The regulated release of bile acid, composed of any of a group of steroid carboxylic acids occurring in bile, by a cell or a tissue. bile acid moving A to the outside of B