Evaluation of the Venous System of Wistar Rat Liver by Injection with Epoxy Resin

The rat is the most widely used experimental model in surgical research due to several factors, including that it is easy to handle and inexpensive. It can be used in investigations related to liver regeneration, liver metastases, or transplant immunology. This study highlights the venous components of the hepatic circulation in the Wistar rat by intravascular injection of a polymer that allows the assessment of the distribution of vessels, regardless of their caliber. Five cadavers of 11-month-old male Wistar rats from the USAMV Cluj-Napoca biobase destined for incineration, were used to highlight the liver venous system. A dye mixture, consisting of epoxy resin-catalyst-blue acrylic dye in a 2:1:1 ratio, was injected. After 24 hours, biological tissues were macerated by immersion in 10% KOH solution for five days. The intrahepatic venous system is represented by the venous branches that continue into the liver lobes. Those vessels follow a parallel trajectory with the hepatic artery branches represented by the right and left ramifications. The right portal vein presents branches to the lateral and medial parts of the right lobe of the liver and the caudate lobe. The left branch of the portal vein has ramificationsfor the lateral and medial parts of the left lobe and the quadrate lobe. The technique of injecting the venous circulation of the liver, followed by tissue maceration, allowed the removal by anatomical dissection of all liver components that permits the identification of all components of the venous system, including the finest venous branches of the hepatic circulation.