9. Liver, Pancreas and Biliary Tree Flashcards
What are some vessels contained within the liver?
- Portal tract
- Portal veins
- Arteries
- Bile ducts
- Central vein
How are hepatocytes arranged in the liver?
In cords with intervening sinusoids
What is the liver divided into?
Classic lobules
What are classic lobules?
A roughly hexagonal area drained by one central hepatic venule
What is an alternate architecture of the liver?
The acinus
What are acini?
Architectural concept based around the blood supply rather than drainage of the liver
Are all hepatocytes equal?
No. Some will be more richly oxygenated than others.
What are the 3 vessels of the portal triad?
- Bile duct
- Portal vein
- Hepatic artery
What are hepatocytes?
Principle functional cells of the liver
What characteristics do hepatocytes have? (8)
- Polyhedral epithelial cells
- Abundant mitochondria
- Large central spherical nuclei
- Prominent nucleoli
- May be binucleate
- Active Golgi apparatus
- Prominent endoplasmic reticulum
- Numerous peroxisomes
What are the 3 important surfaces of a hepatocyte?
- Sinusoidal (70%)
- Canalicular (15%)
- Intercellular (15%)
What is the importance of the sinusoidal surface of a hepatocyte?
Permits exchange of material with blood (Space of Disse)
What is the importance of the canalicular surface of a hepatocyte?
Permits excretion of bile
What are sinusoids?
Highly specialised blood vessels
Name 3 characteristics of sinusoids.
- Thin discontinuous fenestrated endothelium
- No basement membrane
- Contains scattered Kupffer cells
Describe the sequence of the intrahepatic biliary tree.
Canaliculi, bile ductules, trabecular ducts, bile ducts
What is the epithelium of the intrahepatic biliary tree?
Simple cuboidal-to-columnar epithelium
What are the 2 main functions of the gallbladder?
- Concentrates and stores bile
- Expels bile via common bile duct into duodenum
What is the epithelia of the gallbladder?
Simple columnar epithelium
What are some specialised characteristics of gallbladder mucosa?
- Microvilli
- Thrown into folds
- Adapted for water and salt absorption
- Connective tissue lamina propria
What is the main function of the exocrine pancreas?
To synthesise and secrete enzymes and bicarbonate-rich fluid into the duodenum
Describe the exocrine pancreas.
Poorly defined fibrous capsule with septa dividng glands into lobules with epithelial cells arranged in acini
Describe acinar cells.
- Epithelial
- Pyramidal shape
- Basally rich in rER
- Apically contain zymogen granules
What are the 4 types of exocrine pancreas ducts?
- Centroacinar cells
- Intercalated ducts
- Interlobular ducts
- Main pancreatic duct
