Here we shall learn where the gallbladder is located in the body, along with its functions, and the diseases affecting it. Have a look!
The gallbladder is a small, green, pear-shaped organ located in the abdominal cavity of vertebrates. It grows to a length of 8 centimeters, and has a diameter of 4 centimeters. The function of the gallbladder is to store the bile secreted by the liver.
Location of the Gallbladder
~ The gallbladder is located beneath the liver. Its location corresponds to the lowest ribs, on the right side of the rib cage.
~ The abdominal cavity in which the gallbladder is located, is termed as the gallbladder fossa, which is nothing but a depression on the undersurface of the liver, between the quadrate and the right lobes.
~ The organs that come in contact with the gallbladder, are the liver, the abdominal wall, the transverse colon, and the duodenum or small intestines.
~ The cystic artery, a branch of the right hepatic artery, supplies oxygenated blood to the gallbladder, while the deoxygenated blood is carried out by the cystic vein. The cystic vein drains the blood into the portal vein.
~ The gallbladder is supplied by nerves of the sympathetic and parasympathetic nervous systems, which arise from the celiac plexus located in the abdomen. In addition to this, the gallbladder contracts in response to the hormone cholecystokinin secreted by the duodenum.
Parts of the Gallbladder
The gallbladder has three parts, which are the fundus, body, and neck.
Fundus: The fundus is the rounded part of the gallbladder that is farthest from the cystic duct, and is covered with peritoneum.
Body: The part of the gallbladder between the fundus and the neck, is called the body. The body lies in contact with the undersurface of the liver.
Neck: The neck is the part of the gallbladder that lies closest to the cystic duct, and it connects the body of the gallbladder to the cystic duct.
The body and neck of the gallbladder is attached to the surface of the liver by the peritoneal covering.
Functions
The gallbladder is the site for storage and concentration of bile, until it is necessary for digestion. It can store about 50 ml of bile.
The primary function of the gallbladder is to aid in the digestion of fats. To carry out this function, it receives bile secreted by the liver through the cystic duct. The liver secretes bile through the left and right hepatic ducts, which come together to form the common hepatic duct. The cystic duct from the gallbladder joins the common hepatic duct to form the common bile duct, which carries bile to the small intestines. The sphincter of Oddi regulates the flow of bile into the small intestines, and when it contracts, the bile flows through the cystic duct into the gallbladder. The bile accumulated in the gallbladder undergoes certain modifications. The function of bile is to emulsify the fats present in the partly digested food, and this is essential for the digestion of fats and lipids. When fatty food reaches the small intestines, it stimulates the release of a hormone cholecystokinin from the mucous membranes present on the walls of the small intestines. The hormone reaches the gallbladder through the bloodstream, and triggers its contraction. This hormone also triggers the relaxation of the muscles of the sphincter of Oddi, facilitating the flow of concentrated bile into the small intestines.
Diseases of the Gallbladder
Gallstones are the most common conditions affecting the gallbladder, and are formed due to the solidification of certain substances present in the bile. While gallstones are mostly harmless, they can sometimes grow bigger and move into the cystic duct, causing a blockage. This condition is more common in people who are above the age of 40 and obese. Also, women are more prone to the condition. A sharp pain in the abdominal region is the most common symptom of gallstones, although a patient may not experience any symptoms for years. The symptoms, if present, worsen after the intake of fatty foods.
In most cases, the treatment comprises oral medications that dissolve the gallstones. Lithotripsy, in which ultrasonic shock waves are used to break the stones into smaller fragments, is also used. The surgical treatment involves removal of the gallbladder by a process termed as cholecystectomy. After the surgery, provision is made for the bile to pass through the ducts directly from the liver to the small intestine. The surgery is simple and there are rarely any complications involved. In rare cases, however, complications such as bleeding, diarrhea, and infection of the cystic duct, may arise. However, these are not a cause of concern, and can be easily treated with medications after consulting a doctor.