Flashcards in GI module 4 Deck (43)
The functional unit of the liver is a hexagonal arrangement. Describe the parts of this.
1. hexagonal hepatocytes and microvasculature
2. central vein at center of hexagon
3. At each corner is a portal triad
What does the microvasculature of the hepatocyte contain?
sinusoid and bile canaliculi
Name the parts of the portal triad
Terminal branch of the hepatic artery
Terminal branch of the portal vein
Terminal bile duct
Describe the pathway of bile
Bile canaliculi drain into terminal bile ducts
Terminal bile ducts drain into R/L hepatic ducts
R/L hepatic ducts merge to form common hepatic duct
Common hepatic "divides" into cystic (gallbladder) and common bile which merges with the pancreatic duct to drain into the duodenum
T/F liver has the ability to regenerate?
What are some of the signaling mechanisms that stimulate liver regeneration?
TGF, HGF, EGF
If 50-60% of the liver is damaged from 4 days of acetaminophen how long will it take for the liver to completely regenerate?
within 30 days.
What are the 2 afferent pathways to the liver and what percent do each supply?
Portal pathway (hepatic portal vein) 75%
Arterial pathway (hepatic artery) 25%
What does the portal pathway primarily supply?
What does the arterial pathway primarily supply?
If there is congestion in the portal vein what levels will increase?
What structures make up the efferent pathway of the liver?
Where do the central veins drain into?
Where do the hepatic veins drain in to?
t/f the liver produces a large amount of lymph?
The hepatic portal vein receives blood from?
The GI tract, spleen and pancreas
What does the hepatic portal vein carry?
A large amount of nutrients from the GI tract, and a relatively small amount of O2
Where does the hepatic portal vein terminate?
Divides into R/L branches and further divides until it finally delivers blood to portal vein
What collateral veins are part of the hepatic portal anastomosis?
When congestion d/t cirrhosis is present what may also be seen on inspection?
Distention of the hepatic portal anastomosis veins
Where does the hepatic artery originate from?
The celiac trunk
Is blood flow from the hepatic artery impaired during cirrhosis?
What acts as a "capillary bed" for hepatocytes?
What 2 vessels do the sinusoid receive blood from?
Terminal branches of hepatic portal veins, and artery
What works to expose hepatocytes to hepatic blood flow?
Where does the sinusoid drain into?
Where are Kupffer cells located?
Surface of the endothelium
What do Kupffer cells function to do?
Phagocytic removal of immune complex
RBC degradation-remove damaged RBC's
SERVES AS EARLY FRONT LIKE DEFENSE AGAINST LIVER DAMAGE
What structure allows nutrients/lipids to travel through the sinusoidal wall and flow to microvilli of hepatocyte?