Liver Flashcards
What is a lobule?
Functional unit of the liver
What is the size/shape of a lobule?
1-2mm diameter hexagon shape
What does the lobule consist of? (6)
- Liver cells (hepatocytes)
- Central hepatic vein
- Sinusoids
- Kupffer cells
- Bile canaliculi
- Portal triads
Describe a hepatocyte
Organized in 2 layered columns converging toward a central vein in a radial pattern
What is the hepatocyte in contact with? What does it do?
Sinusoid blood- liberates substances in the blood
What does a sinusoid do?
Blood enters at the periphery of the lobule and travels to the central vein via sinusoid
Where is the sinusoid located?
B/w the hepatocytes columns
What type of blood does the sinusoid consist of? Of this blood what % does each contain?
80% Portal venous blood
20% Hepatic blood
Where are kupffer cells located?
Scattered along columns of the hepatic cells
What part of the system is the kupffer cells included in?
Reticuloendothelial system
What is the function of the kupffer cells?
Ingest and destroy foreign material (WBCs, RBCs and bacteria) and cleanse the blood
Where are the bile canaliculi located?
B/w 2 layers of the liver column cells
Are the bile canaliculi the smallest part of the biliary tree?
Yes
What divides the bile and sinusoid blood?
1 row of hepatocytes
Describe the flow of bile
Biles freed from the hepatocytes to the canaliculi- flowing towards larger bile ducts at the outer edge of the liver lobule
Converge to form larger ducts which unite to form the right and left hepatic ducts
Right and left hepatic ducts join at the porta hepatis to form the CHD
Cystic duct joins the CHD to form the CBD and drains into duo
What does the portal triad consist of?
CBD, PV and HA
Where are the portal triads located?
At the outer edge of the lobule
How many portal triads serve a single lobule?
Several
How does blood travel towards the central vein?
Blood enters periphery of the lobule via sinusoids
What state should the blood be in when in the central vein?
Clean of toxins and rich in liver secretions
What veins does the central hepatic vein converge with?
Converges into larger veins and unites into the hepatic veins and drains into IVC
Liver is the primary center for what function?
Metabolism
How many activities does the liver preform?
500 different activities
How are the functions carried out?
Hepatocytes, Kupffer cells and bile cells
What % of the liver tissue makes up hepatocytes?
80%
What is bile made of? (6)
- Bile salts
- Cholesterol
- Conjugated of steroid hormones
- Pressor amines
- Water
- Bilirubin
What is bilirubin?
Product breakdown of hemoglobin
What cells aid in the production of bilirubin? (Breakdown of RBCs)
kupffer cells and other RE cells
What forms bile salts?
Cholesterol in hepatic cells
What is the function of bile?
Emulsifies fats and aids in the production of fatty acids in the GI tract
How much bile is produced in a day?
700-1200ml/day
Where is bile stored?
GB
What is unconjugated bilirubin?
Fat soluble and not excreted by urine
Toxic to tissues
What is conjugated bilirubin? What structure secretes it?
Non-toxic and water soluble
Secreted from liver into bile canaliculi