Drug-Induced Hepatic Injury Exam 3 Flashcards
What supplies the liver with blood?
- portal vein
- hepatic artery
portal vein
- approximately 75% of the blood supply to the liver is derived from the portal vein, which drains the intestinal tract, spleen, and pancreas
- blood is enriched with nutrients and other absorbed xenobiotics and is poor in oxygen
hepatic artery
the remainder of the hepatic blood flow (~25%) comes from the hepatic artery, which delivers well-oxygenated blood from the systemic circulation
sinusoids
where the blood from the hepatic artery and portal vein mixes
How does oxygen content change going from the portal area to the central hepatic vein?
oxygen content diminishes
What are the concepts that help describe the appearance and function of the liver?
- Hepatic lobule
- Acinus
Hepatic lobule
- A hexagon with the central vein at the center and the portal triads at the angles.
- The portal triad
- Cords of hepatocytes are oriented radially around the central hepatic vein.
What makes up the portal triad?
- portal vein
- common bile duct
- hepatic artery
Acinus
Located between two central veins and subdivided into three metabolically distinct zones: Zone 1, 2, 3
What are the cells and cell types that make up the liver?
- Hepatocytes
- Endothelial cells
- Kupffer cells
- Stellate (Ito) cells
Hepatocytes component
- liver parenchyma cells
- make up 80% of liver mass
Functions of hepatocytes
- Glycogen storage and gluconeogenesis
- Formation of bile and biliary excretion
- Biotransformation and detoxification
- Synthesis of plasma proteins (clotting factors, protein)
Endothelial cells characteristics
- Thin and fenestrated
- Carrying blood; secrete cytokines
- May produce reactive oxygen and nitrogen compounds in response to various stimuli
Kupffer cells function
- aka fixed macrophages
- Scavenge cell debris, particulates, endotoxin, etc
- Secretion of cytokines (e.g. tumor necrosis factor) and reactive oxygen and nitrogen radicals in response to endotoxin lipopolysaccharide (LPS) or ischemiareperfusion
Stellate (Ito) cells function
- Primary site for storage of fat and vitamin A
- Produce collagen, proteoglycans, and adhesive glycoproteins
- Are causal in fibrosis and are associated with the development of cirrhosis