Portal vein is formed by union of which of the following veins?
a) Superior mesenteric vein & Splenic vein
b) Superior mesenteric vein & inferior mesenteric vein
c) Inferior mesenteric vein & Splenic vein
d) inferior mesenteric vein & Hepatic vein
Correct Answer - A
Portal vein is formed by the union of Superior mesenteric vein (SMV)
and splenic vein posterior to the neck of pancreas. The inferior
mesenteric vein drains into the splenic vein.
- The hepatic portal vein pass posterior to the first part of duodenum,
in the free edge of lesser omentum. - At the porta hepatis, it divides into right and left branches
supplying the right and left lobes of the liver. - Within the sinusoids of the liver, hepatic portal blood and
oxygenated blood from the hepatic artery mix together and come
into contact with the hepatocytes, where metabolites such as
products of digestion are exchanged. - Blood from the sinusoids empties into hepatic veins draining the
liver and in turn drain into IVC, and blood is returned to heart.