1. Structure of the liver, gallbladder and pancreas
Sanjaya Adikari
Department of Anatomy

2. Hepatic ducts
Common hepatic duct
Cystic duct
Common bile duct
Pancreatic duct
Ampulla of Vater
Sphincter of Oddi

3. Ampulla of Vater

4. Liver Largest gland in the body Second largest organ
Principal metabolic organ
70-80% of its blood comes from portal vein
20-30% of its blood comes from hepatic artery
Everything absorbed, except lipids, enter it

5. Functions of the liver Fat metabolism Carbohydrate metabolism
Protein metabolism
Storage
Drug, toxin and alcohol metabolism
Secretion of bile

6. Liver Formed by hexagonal structural units called liver lobules
Pig liver lobules have clear connective tissue boundaries
Formed by hexagonal structural units called liver lobules
Lobules have a central venule
Lobules are surrounded by portal tracts

7. Liver
Human liver lobules do not have clear connective tissue boundaries
Lobules are defined by the arrangement of portal tracts around central venule

8. Liver

9. Structure of a lobule The main functional cell is hepatocyte
Hepatocytes are arranged in plates
Between hepatocyte plates are sinusoids and bile canaliculi
Sinusoids are lined with fenestrated endothelium
Between the endothelium and the hepatocytes lie the space of Disse

10. Structure of a lobule
Blood from the branches of hepatic artery and portal vein enter the sinusoids
Blood is drained by central venule, branch of hepatic vein
Bile flow in the bile canaliculi is opposite to the blood flow in the sinusoids
Central venule collects blood from one lobule
Portal tracts supply several lobules around them

11. Arrangement of portal tracts and central venules
Bile ductule

12. Liver

13. Arrangement of sinusoids and bile canaliculi
Bile ductule

14. Liver

15. Liver

16. Lining cells of sinusoids
Three types
Endothelial cells
Kupffer cells
Stellate cells or hepatic lipocytes
Stores vitamin A
In response to liver injury produces large amounts of collagen causing fibrosis that may lead to hepatic cirrhosis

17. Kupffer cells These are phagocytic cells
Removes aged erythrocytes and particulate matter from circulation

18. Portal tracts (Portal triads)
Branch of the hepatic portal vein
Branch of the hepatic artery
Bile ductule

19. Limiting plate
The layer of hepatocytes immediately bordering the portal tract is called the limiting plate
The limiting plate gets disturbed in diseases like hepatitis

20. Sinusoids and spaces of Disse
Endothelium has no basement membrane
Space of Disse lies between the endothelium and hepatocytes
Space of Disse drains into the lymphatics of portal tracts

21. Hepatic acinus Roughly diamond shaped
Consists of liver parenchyma centred around a portal tract
Acinus is divided into three zones
Zone 1 - Receives most oxygenated blood
Zone 3 - Receives least oxygenated blood

22. Gallbladder Bile in the common hepatic duct enters the gallbladder
Bile is stored and concentrated in it
Capacity is about 100 ml
Contracts in response to CCK
Bile is an emulsifying agent

23. Gallbladder
Simple columnar epithelium

24. Pancreas  Cells - Insulin  Cells - Glucagon  Cells - Somatostatin
Has exocrine and endocrine components
Under the influence of autonomic nerves, gastrin and CCK
Secretes enzymes that digest proteins, lipids and carbohydrates
Secretes insulin, glucagon, somatostatin, and some other hormones
 Cells - Insulin
 Cells - Glucagon
 Cells - Somatostatin

26. Pancreatic acini
Pyramidal shaped cells
Lumen
Intercalated ducts