Gallbladder

The gallbladder is a small hollow intraperitoneal organ located beneath the liver. Its primary function is to store and concentrate bile produced by hepatocytes in the liver before releasing it into the duodenum during digestion, particularly after ingestion of fatty foods. The release process is regulated by neurohormonal signals including cholecystokinin, which triggers contraction and emptying through relaxation at sphincters controlling outflow. The epithelium actively absorbs sodium ions from stored bile, concentrating it several-fold while protecting itself with mucus secretion. The coordinated filling-and-emptying cycle controls enterohepatic circulation and helps regulate lipid absorption. Dysfunction can lead to stone formation (gallstones), inflammation (cholecystitis), or rarely malignancy. While essential for optimal fat digestion under normal physiology, removal does not preclude survival; however, cholecystectomy alters enterohepatic cycling with potential long-term metabolic consequences including increased risks for certain cancers. The gallbladder should not be considered a canonical molecular drug target; rather it serves critical physiological roles within digestive health.

Other names

biliary vesicle

For drugs like ursodeoxycholic acid: Reduces cholesterol saturation in bile, dissolves cholesterol stones. For cholecystokinin analogs/agonists: Stimulate contraction/emptying by mimicking physiological hormone action. Note: No direct molecular targeting—actions are indirect via modulation of function or content.