Gastrointestinal Lecture 6 Part 1 Functional Anatomy of the Liver Flashcards
1
Q
What do we know about the liver already?
A
2
Q
Functional anatomy of the liver
A
3
Q
Functional anatomy of the liver: circulation
A
- The absorptive segments of the gastrointestinal tract drain into the hepatic portal vein
- The liver receives arterial blood supply from the aorta, and venous drainage via the vena cava
- The liver also receives blood supply from the hepatic portal vein, which drains from the stomach and intestines = “hepatic portal system”
- Substances absorbed in the intestine (nutrients, toxins, drugs) must pass through the liver and be processed before entering the general circulation
4
Q
Functional anatomy of the liver: hepatic lobules
A
- Structure has central veins
- Portal triad
- chords of hepatocytes
5
Q
Parts of the portal triad
A
- branch of bile duct
- branch of hepatic portal vein
- branch of hepatic artery
6
Q
How does the portal triad of the liver work?
A
- Arterial blood flows from hepatic artery to central vein oxygenating hepatocytes*
- Blood from the portal vein percolates between hepatocytes, emptying into the central vein*
- Bile produced by hepatocytes drains into the bile duct*
7
Q
What happens to Arterial and portal vein blood
A
percolates towards the central vein in hepatic sinusoids
8
Q
How does blood interact with hepatocytes
A
Blood travelling through the hepatic sinusoids can flow through gaps in the endothelial cell layer (fenestrations), entering the space of Disse and coming in direct contact with the hepatocytes.