L8 - Liver Disease Flashcards
Where is liver located?
• It is located beneath the diaphragm in the right upper
quadrant of the abdomen and is protected by the ribs.
• Divided into left and right anatomic lobes by the
falciform ligament, an anterior extension of the
peritoneal folds that connects the liver to the diaphragm
and the anterior abdominal wall.
Liver anatomy?
Hepatic vein
• blood returning to heart
Hepatic artery
• bringing fresh blood from heart
Portal vein
• bringing blood from intestines
Bile duct
• bile draining to intestines
Liver blood supply?
Receives ~ 1500 ml of blood per/min; ~25% of the cardiac output. The liver has a dual blood supply:
1. Hepatic artery , a branch of the celiac axis, provides oxygen-enriched arterial blood.
2. Portal vein , which carries blood from the spleen and nutrient enriched blood from the GI tract, supplies ~ 70% of the blood supply
**check slide (7/47)
Venous drainage from the liver?
Venous drainage from the liver ultimately converges into the right and left hepatic veins, which exit on the posterior surface of the liver and join the inferior vena cava near its entry into the right atrium.
Liver organization models?
Anatomical model - the liver lobule
Functional model - the liver acinus
The liver acinus zones: Zone 1?
Zone 1:
• Rich with lysosomes and mitochondria
• Oxygen rich
• Least susceptible to hypoxia/necrosis
• Highest degree of metabolic activity
• Provides base for hepatic regeneration
The liver acinus zones: Zone 2?
Zone 2: intermediate.
• Contains primarily
hepatocytes, site of
metabolic action
The liver acinus zones: Zone 3?
Zone 3:
• Enriched with endoplasmic reticulum
• Low oxygen tension
• Susceptible to hemodynamic stressors
• Primary site for drug detoxification (phase I and II metabolism)
Liver cellular architecture?
**Check slides (12/47)
Liver cellular architecture: Hepatocytes
70% of liver mass. Functional cells of the liver.
Site of metabolic and synthetic functions; divide
under stress and cytokine activation.
Liver cellular architecture: Kupffer cells
Specialized, self
renewing, long lived
macrophages that line the walls of the
sinusoids that form part of the reticulo
endothelial system. Part of innate immune
system (non specific targeting of foreign
antigens & antigen antibody complexes)
Liver cellular architecture: Stellate cells=Ito cells
Between hepatocytes and endothelial cells; store
fat soluble vitamins (quiescent); contractile
properties, involved in regulating blood flow;
synthesize collagen during fibrosis (stimulated)
Liver cellular architecture: Hepatic endothelial cells
Fenestrated cells that line sinusoids. Play role in
regulating intrahepatic resistance to blood flow via
NO (vasodilator).
Liver cellular architecture: Dendritic Cells
Localized around central vein; play an immune role
in antigen presentation and activation of T
lymphocytes.
4 main physiologic functions of the liver?
Metabolism
Synthesis
Excretion
Storage