GI: The Liver Flashcards
Where does the arterial and venous blood from the hepatic artery and hepatic portal vein mix?
Sinusoids
What is at the centre of each liver lobule?
central vein (branch of the hepatic vein)
What is located in the triad at each of the six corners of the lobule?
A branch of the hepatic portal vein
a branch of the hepatic artery
A bile duct
Where does blood flow in the liver lobule?
Inwardly towards the central vein
Where does bile flow in the lobules
Secreted from hepatocytes and flows outwardly towards the bile ducts through canaliculi
What does the basolateral membrane face?
The space of disse
What is present on the apical membrane>
The canaliculi
What is contained in the sinusoidal space?
endothelial cells that are fenestrated
kuppfer cells
stellate (ito) cells
What are kuppfer cells?
Resident macrophages in the sinusoidal space which degrade old erythrocytes
What are stellate (ito) cells?
within the space of disse
Store vitamen A
Deposit collagen whihc can lead to fibrosis and cirrhosis
What is the sequence of the intrahepatic bile system?
Canaliculi Terminal bile ductules Perilobar ducts Interlobular ducts Septal ducts Lobar ducts Two hepatic ducts Common hepatic duct
What is the composition of bile?
Secretion of hepatocytes
Secretion of bile duct cells (cholangiocytes)
What is hepatic (primary) bile composed of?
Bile acids (cholic and chenodeoxycholic)-- form bile salts with NA and K Electrolytes Water Lipids and phospholipids Cholesterol IgA Bilirubin
Describe the secretions of bile duct cells?
Similar composition to pancreatic juice - alkaline
What does the alkaline pH of bile duct secretion contribute to?
Micelle formation
Neutralization of chyme
pH adjustment for digestive enzyme action
protection of the mucosa
