Liver (and a little of Gallbladder) Flashcards
What is Glisson’s capsule?
A thin layer of fibrous connective tissue that encapsulates the liver.
It is also continuous with the connective tissue that surrounds each lobule.
What are the contents of the Portal Triad? Why is its name considered a bit of a misnomer?
It contains FOUR structures of import:
- Common Hepatic Duct
- Portal Hepatic Vein
- Proper/Common Hepatic Artery
- Associated lymphatics
What kinds of blood does the liver receive? Which vessel brings the most blood to the Liver?
Both deoxygenated (venous) and oxygenated (arterial) blood.
Note that the deoxygenated blood is nutrient-RICH.
The Portal VEIN brings 70% of the blood going to the liver.
Describe the blood pathway throughout the liver, from entrance to exit.
Portal Hepatic Vein/Proper Hepatic Artery -> Distributing vessels between (classic) lobules -> Sinusoids -> Central Vein (venule) -> Sublobular vein -> Hepatic Veins -> IVC -> Heart RA
What are the three types of hepatic organization?
Classic Lobule
Portal Lobule (exocrine organization)
Liver Acinus
What is the Portal Lobule transporting? What is a clue for understanding this function?
It transports bile out of the liver.
Note that the portal lobule is centered around the Portal tract, which contains the bile duct (and would lead to the Common Hepatic Duct).
In the Liver Acinus, where are the 3 zones, and which zones are affected first/last during an episode of heart failure?
Zone 1 is located adjacent to the classic lobule walls, and Zone 3 is located by the Central Vein.
Zone 3 will show ischemic necrosis first and will have a more difficult time regenerating (if at all), and Zone 1 will be the first to regenerate and last to die.
In the case of alcoholism/alcohol poisoning, how are the zones of the Liver Acinus affected?
Reversed from how they would be affected in an episode of heart failure.
What are the two cell types of the Sinusoids?
Endothelial Cells and Kupffer Cells.
What is a notable feature about the Endothelial cells in Sinusoids?
They have no tight junctions linking them together and have many fenestrations, making them very leaky.
What are Sinusoids, anyway?
Small spaces between the hepatocyte cords of Liver lobules.
What are Kupffer Cells?
They are macrophage-like cells that function somewhat like the ‘immune system’ of the liver, filtering out particulate/unwanted matter from the blood.
What is the function of the space of Disse? Where is located?
It is a sort of ‘lymphatic drain’ for the lobule. It mostly contains plasma and some proteins. It is the space between the endothelial cells and hepatocytes.
Note: the hepatocytes will project microvilli into this space to increase surface area for absorption.
What is the function of the Ito cells?
They normally produce/store vitamin A, which is important for vision. They also produce Extracellular Matrix during recovery after the liver has sustained injury.
What happens when the Ito cell is in a pathological state?
It becomes fibrotic, spewing out excessive collagen into the space of Disse and basically clogging them up.
