Liver Lobule

Description

Centered on a terminal hepatic venule (central vein), the lobule is rendered as a classic hexagonal (polygonal) unit with hepatocyte plates arranged in radial cords extending from the periphery toward the center. Portal tracts sit at the angles, with branches of the portal vein (blue), hepatic artery (red), and interlobular bile duct (green) grouped as a portal triad. Between the hepatocyte cords, hepatic sinusoids course centripetally toward the central vein, while bile canaliculi run in the opposite direction, draining centrifugally toward the bile ductules at the limiting plate. Orientation matters here because lobular microanatomy explains liver function and injury patterns better than gross visceral anatomy ever can. Blood from the portal venule and hepatic arteriole mixes in the sinusoids and reaches the central vein after passing hepatocytes that differ by zone, a concept used to teach acinar Zones 1 to 3 and why centrilobular (Zone 3) hepatocytes are hit hardest in ischemic hepatitis and acetaminophen toxicity. The portal triad also anchors pathology: portal-based inflammation and fibrosis in chronic viral hepatitis and primary biliary cholangitis start around the bile ducts, then remodel lobular architecture into bridging fibrosis and cirrhosis. Use this artwork in histology and GI blocks to link sinusoidal flow, bile drainage, and metabolic zonation, or in hepatology and pathology texts when explaining portal triad lesions, centrilobular necrosis, and early cirrhotic nodule formation. It also fits operative and interventional teaching when correlating portal venous inflow, hepatic arterial supply, and biliary drainage before hepatectomy or liver transplantation. Anatomical accuracy verified by SciePro's Medical Advisory Board.