DEV2022 – Lecture 16
It is attached inferiorly to the diaphragm. There is no visceral peritoneum that
covers that area hence its called the bare area.
Exocrine organ = secrete products into a duct. Secretes into the bile duct.
Umbilical and vitelline vessels that supply the liver.
Falciform ligament was a mesentery in the embryo. IN adults, it is still attached
to the inner aspect of the abdominal wall. Inside of it is a round ligament of the
liver, where it isn’t a ligament, but a remnant of the umbilical vessels that come
from the placenta, enter the abdo cavity, pass through and to the liver as a vessel,
before exiting to join the inferior vena cava, and the heart. At the time of birth,
that pathway is closed off, leaving behind a closed off collapsed vessel.
Nutrients and toxins heads towards the liver courtesy of the hepatic portal vein.
Inferior vena cava is not the vein that takes care of the venous drain.
Ciliac, superior mesentery and inferior mesentery have counterparts in the
venous system where they join up and forms the portal vein.
Tissue macro and micro organization:
The function of the liver is to filter and extract the blood that it receives. The
blood vessels from the capillaries are rather leaky.
Tiny gaps = blood vessels
Highly vascular organ
Black lining = collagen fibres (reticular fibres) where they support the radial
arrangement of blood vessels in each prism or lobule.
In some disorders, there is an overproduction of these fibres where the liver fails
Liver lobule concept:
Each lobule has a hole in the middle, which is the central vein. There are
radiating spokes (sinusoid, which are special capillaries).
The cords are the sheets of liver cells. There are gaps between them (sinusoids).
The central vein is in the middle. And at the angles of the polygon/prism, red =
arterial (hepatic artery from ciliac trunk (foregut artery)), blue = venous (portal
vein from gut), green = bile
The liver lobule:
Blood coming into each of our polygon, comes in at the edge and the blood in
these vessels drain into the capillari