A hepatic lobule is a small division of the liver defined at the histological scale. It should not be confused with the anatomic lobes of the liver (caudate lobe, quadrate lobe, left lobe, and right lobe), or any of the functional lobe classification systems.
Dividing liver tissue into lobules can be confusing, because the lobes are defined in different ways depending upon the function one is analyzing:
|"classic lobule"||hexagonal, divided into centrilobular, midzonal, periportal parts||endocrine|
|"acinus"||diamond shaped, divided into zone 3, zone 2, zone 1||blood/disease|
Sometimes the term "hepatic lobule" only refers to the "classic lobule".
When described as an "acinus lobule", the portal triad (portal vein, artery, bile duct) is at the centre and adjacent two central veins are at the periphery of the lobule. The liver parenchyma would be divided into zones based on oxygen supply. Zone 1 encircles portal tract where oxygen rich blood enters via hepatic arteries where as zone 3 being farthest has poorest oxygenation.
- Histology image: 15401loa – Histology Learning System at Boston University
- Histology at siumed.edu
- Histology at okstate.edu
- Histology at webmd.idv.tw. Not labeled in English, but overlapping shapes are clearly visible
- UIUC Histology Subject 923