Liver -- is responsible for many different functions and is unusual in being supplied by both arterial blood (for oxygen) and venous blood (with nutrients for processing).

Review the structural organization of the liver parenchyma (Fig. 16-11), noting inflow of blood to lobules from branches of both the hepatic artery and hepatic portal vein and outflow through central venules to branches of the hepatic vein. Note also how bile originates within lobules and is drained via branches of the bile duct. A simplified version of one liver lobule in transverse section is shown in the diagram on the next page.

List several unrelated functions of hepatocytes.

Clinical note: Hepatitis involves infection or inflammation of hepatocytes and other epithelial components in the liver. Cirrhosis involves excessive proliferation of fibroblasts and collagen deposition in the stroma of the liver. Hepatocytes have a remarkable capacity for regeneration, but chronic, long-term alcoholism leads to the death of these cells and cirrhosis.

Examine a section of the liver (slides 24, 29 and 141) and with the low power objective, locate a set of portal tracts outlining a lobule (Fig. 16-12). With the higher power objectives, identify the central venule in the center of the lobule (Fig. 16-13a) and the "triad" of components in a portal tract, namely branches of the hepatic portal vein, hepatic artery, and bile duct (Fig. 16-13b).

What do the 3 components of a “portal triad’ transport?

What fourth structure is also usually there?

Detail of the hepatic lobule.