What part of the liver does the portal vein carry blood into?

The portal vein is responsible for carrying blood rich in nutrients from the gastrointestinal tract and spleen directly into the liver. Specifically, the blood from the portal vein enters the hepatic sinusoids, which are specialized capillary-like vessels within the liver.

These sinusoids are crucial for the liver’s function, as they allow for the exchange of substances between the blood and liver cells, known as hepatocytes. The unique structure of the sinusoids, which have larger gaps between endothelial cells compared to regular capillaries, facilitates the uptake of nutrients, medications, and other substances from the blood. This is a vital step in the metabolic processes of the liver.

In contrast, the central vein collects blood from the sinusoids and drains it into the hepatic veins, which eventually return the blood to the general circulation. The portal system refers to the network of veins that carry blood to the liver, but the specific role of the portal vein is to deliver blood directly into the sinusoids for processing.