Passage of Blood Cells Through a Liver Lobule

Description

Radial plates of hepatocytes form a hexagonal hepatic lobule, converging toward a centrally placed central vein (terminal hepatic venule). At the lobular periphery, portal tracts sit at the corners, where a portal venule and hepatic arteriole deliver blood into sinusoidal spaces that run between hepatocyte cords from peripheral to central. Kupffer cells line the sinusoidal lumen, while the space of Disse separates sinusoidal endothelium from hepatocytes; bile canaliculi run in the opposite direction, carrying bile centrifugally toward bile ductules in the portal triads. Flow direction matters. This arrangement underpins classic zonation, with periportal (zone 1) hepatocytes closest to the portal triad and centrilobular (zone 3) hepatocytes adjacent to the central vein. Zone 3 is most vulnerable to hypoxic injury in shock and to acetaminophen toxicity, and congestion around the central vein explains the centrilobular pattern in right-sided heart failure (nutmeg liver). Portal-to-central blood transit also frames how inflammatory cells and tumor cells interact with sinusoidal endothelium during hepatitis, sepsis, and hepatic metastasis. Use this illustration in histology and organ-system physiology teaching to anchor blood and bile flow, sinusoidal microanatomy, and metabolic zonation in a single spatial model. It also suits hepatology and pathology content on ischemic hepatitis, drug-induced liver injury, and congestive hepatopathy, plus surgical and interventional discussions where portal inflow and hepatic venous outflow are conceptually separated. Anatomical accuracy verified by SciePro's Medical Advisory Board.