Liver blood flow and pathogenesis

[Monique]

Interesting fact:

The liver is an organ that filters blood that comes from the digestive tract, blood comes in one side and goes out another.

Researchers wondered whether pathologies could arise when the wrong 'type' of blood enters the liver, fresh blood might have certain cell-mediators in them that alter gene expression and thus regulate glycolysis/gluconeogenesis.

So they change the 'type' of blood that enters the liver, by rerouting certain bloodvessels. They did not find any difference in gene expression of target genes.

BUT pathologies are known where liver failure develops when the right heart ventricle is unable to pump blood sufficiently, causing blood to return to the liver.

So the researchers looked at gene expression when blood was entering the liver from the wrong direction, AND! it was different!

Strange that wrong blood entering from one side doesn't have an effect, but wrong blood entering from the other side does :)

[Monique]

Could someone explain the following for me:

In a lecture it was stressed that the liver has a left and a right side. It was also stressed that biochemical opposite pathways will occur in different liver cells (to prevent futile cycle). Futher more it was noted that there are periportal and pericentral cells that have different gene expression patterns (blood flows out of a periportal vessel through hepatocytes towards a pericentral vessel).

Now I am trying to make these three concepts clear.

These two liver sides (left and right) are they really biochemically different, or are they just anatomically divided by the branching bloodvessels.

These periportal and pericentral hepatocytes, this is where the division of pathways takes place? Synthetic pathways in one celltype and metabolic in the other, or am I confused?