Introduction

• The gallbladder is located between the lobes of the liver and may be visualized during laparotomy from the visceral surface, between the right medial and quadrate lobes.
• The gallbladder stores bile; this is produced by hepatocytes and transported through intralobular bile canaliculi, along the hepatic bile duct system and into the gallbladder via the cystic duct. The cystic duct joins the common bile duct which conveys bile to the proximal duodenum at the major duodenal papilla.
• Bile stored in the gall bladder is concentrated substantially by absorption of water. The gallbladder epithelium further modifies the bile by absorption of various electrolytes and secretion of bicarbonate-rich mucin.
• The Sphincter of Oddi, at the duodenal papilla, controls bile flow into the duodenum.
• Gallbladder contraction, relaxation of the Sphincter of Oddi and therefore bile secretion is stimulated by cholecystokinin (CCK) from the proximal small intestine in response to food, particularly long chain fatty acids, in the lumen.
• The gallbladder and sphincter are under autonomic control: bile release is stimulated by parasympathetic innervation.
• The arterial supply to the gallbladder is from the cystic artery from the left branch of the hepatic artery. Interruption of this solitary supply to the gallbladder results in ischemic necrosis, such as is seen following traumatic avulsion of the artery or thromboembolism.
• The gallbladder is not an essential structure; bile production and flow continues in patients following cholecystectomy.
• The minor pancreatic duct opens next to the bile duct at the major duodenal papilla. The accessory (larger) pancreatic duct opens to the intestinal mucosa about 1-2 cm away. Pancreatic pathology (such as inflammation Pancreatitis: acute Pancreatitis: chronic or neoplasia Pancreas: neoplasia ) is a common cause of biliary obstruction in dogs.

Diseases of the gallbladder and biliary tract

Diagnostic procedures

Drug therapy

Further Reading

Publications

Refereed papers

• Recent references from PubMed and VetMedResource.

Other sources of information

• Center S A (2009) Diseases of the gallbladder and biliary tree. Vet Clin North Am Small Anim Pract 39 (3), 543-598 PubMed.
• Thrall D E (ed) (2007) Textbook of Veterinary Diagnostic Radiology. 5th edition, Saunders, Elsevier, St. Louis.
• Bishop Y (ed) (2004) The Veterinary Formulary. 6th edition. Pharmaceutical Press, London.
• Greene C E (ed) (2000) Infectious diseases of the Dog and Cat. 3rd edition. Saunders, Elsevier, St. Louis.
• Dyce K M, Sack W O, Wensing C J G (1997) Textbook of Veterinary Anatomy. 2nd edition, Saunders, Elsevier, St. Louis.