Liver And Gall Bladder Flashcards
What are the livers two sources of blood?
Portal vein and hepatic artery
What is the space of Disse?
What does it contain?
Fluid filled space between endothelial cells and hepatocytes (space is continuous with plasma). Interface for interaction between liver and blood
Contains Stellate cells
What are 2 functions of stellate cells?
Store vit A
Can synthesize collagen and thus can cause hepatic fibrosis
What are the two models describing the arrangement of the hepatic parenchyma?
Classical subunit is hepatic lobule
Classical subunit is hepatic acinus
In the hepatic lobule model, what is the centre and what is the periphery? What is the shape?
Centre: hepatic venule or central venule
Periphery: portal venule hepatic arteriole bile duct, lymphatics, nerves
Shape: hexagonal
In the hepatic acinus model, what is the centre, what is the periphery, and what is the shape?
Centre: terminal afferent branches of the portal venule and the hepatic arteriole
Periphery: hepatic venules
Shape: diamond shape
What are the 3 zones and which is most and least oxygenated?
Zone 1 = periportal (most oxygenated)
Zone 2 = midlobular
Zone 3 = centrilobular (least oxygenated)
What species is the gall bladder absent in? Where does the common bile duct empty into?
Horse and rat
Duodenum
What are the 5 normal liver functions?
- Bilirubin metabolism
- Bile acid metabolism
- Carbohydrate metabolism
- Lipid metabolism
- Protein synthesis
What type of icterus is caused by an increase in the breakdown of RBCs?
Prehepatic icterus
What is the cause of hepatic jaundice?
Decreased uptake of bilirubin due to liver disease (bilirubin accumulates because the liver is not removing it from the blood)
What is the cause of post-hepatic icterus?
Decrease hepatic excretion of bilirubin with bile (cholestasis)
What is the most common type of icterus in ruminants?
Prehepatic icterus
What species develops physiologic icterus with starvation? Why?
Horses
Bilirubin uptake is energy dependent and is decreased during starvation
What is random distribution of degeneration and necrosis caused by?
Bacteria, viruses, Protozoa
What are the 5 types of zonal distribution of degradation and necrosis?
Centrilobular
Paracentral
Periportal
Midzonal
Bridging necrosis
What are the 2 common causes of centrilobular pattern necrosis?
Toxins requiring metabolic activation
Passive congestion of the liver
Describe the paracentral pattern of necrosis
Involves only a wedge around the central vein (one acinus affected)
What is the term that describes necrosis of an entire hepatic lobule or contagious lobules?
Massive necrosis
What are the two types of cholestasis? What is affected? What causes it?
Intrahepatic cholestasis- affects bile caniliculi or ductules within the liver, caused by liver injury (fibrosis)
Extrahepatic cholestasis- affects extrahepatic bile duct, caused by obstruction due to a mass within or outside of the lumen. Will lead to intrahepatic cholestasis
When will you see regenerative nodules?
Extensive loss of hepatocytes and loss of extracellular matrix scaffold (reticulin)
What are the 2 differentials when you see regeneration nodules (lumps and bumps)?
Neoplasia and granulomatous inflammation
What is happening when a liver is small, firm and pale white and may have a nodular appearance to it?
Fibrosis
What are the 3 processes of end stage liver (cirrhosis)?
Degeneration and necrosis
Regeneration (regenerative nodules)
Fibrosis
What is the definition of hepatic failure?
Loss of adequate hepatic function as a consequence of either acute or chronic hepatic damage
What are the 4 consequences of hepatic failure?
Hepatic encephalopathy
Metabolic abnormalities
Vascular and hemodynamic alterations
Cutaneous manifestations
What is an example of vascular and hemodynamic alteration?
Acquired portosystemic shunt which is an abnormal vascular communication between the portal vein and the systemic circulation
What are the two types of cutaneous manifestations?
Superficial necrolytic dermatitis
Photosensitization secondary to hepatic dysfunction