Gallbladder
The gallbladder (or cholecyst) is a pear-shaped hollow organ that is located right under the liver. It is connected to the liver by the biliary tract.
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2 Microscopic anatomy 3 Function 4 Role in disease 5 External links |
Anatomy
Not all mammals have gallbladders. The rat, for example, does not have a specialised organ for the storage of bile.
The gallbladder is connected to the main bile duct through the gallbladder duct (cystic duct or, in Latin, ductus cysticus). The main biliary tract runs from the liver to the duodenum, and the cystic duct is effectively a "cul de sac", serving as entrance and exit to the gallbladder.
Vascularisation is by the cystic artery and vein, which run parallel to the cystic duct.
Microscopic anatomy
The gallbladder has an epithelial lining characterised by recesses (called Aschoff's recesses), which are pouches inside the lining. Under the epithelium there is a layer of connective tissue, followed by a muscular wall that contracts in response to cholecystokinin.
Function
The gallbladder stores bile, which is released when fat-containing food enters the digestive tract, stimulating the secretion of cholecystokinin (CCK).
Role in disease
Cholelithiasis
Up to 25% of all people have gallstones, composed of cholesterol, lecitin and bile acids. These can cause colicky shooting abdominal pain, usually in relation with the meal, as the gallbladder contracts and gallstones pass through the bile duct. Surgery (cholecystectomy) is the most therapy for gallstones. It can be performed laparoscopically, and it is in fact one of the most common procedures done through the laparoscope.
People at an increased risk of cholelithiasis are people who are 5 F's:
- Female
- Fat (obesity)
- Fair (Caucasian)
- Forty (middle-aged)
- Fertile (the risk is increased in pregnancy)
Cholecystitis
- ''Please refer to main article: Cholecystitis
Choledocholithiasis
When gallstones obstruct the common bile duct, the patient develops jaundice and liver cell damage. It is a medical emergency, requiring endoscopic or surgical treatment.
| Digestive system |
| Mouth - Pharynx - Esophagus - Stomach - Pancreas - Gallbladder - Liver - Duodenum - Jejunum - Ileum - Colon - Cecum - Rectum - Anus |