Interpretation of Zonal Lesions by Different Concepts of the Hepatic Lobule

Zonal lesions in the hepatic lobules observed in drug-treated rats, dogs, and monkeys or spontaneously diseased monkeys were considered in reference to the different concepts of the hepatic lobule in order to understand the significance of zonal lesions of the liver correctly. Lesions due to congestion appeared at the periphery of the portal lobule of Mall's concept. Incipient changes due to severe anemia occurred in a triangular shape at the center of the classical lobule where the apices of primary lobules become confluent as proposed by Matsumoto and Kawakami. Drug-induced centrilobular necrosis appeared evenly around the central venules showing clear contrast with the change observed in anemia. Periportal necrosis was located along the portal tract at the periphery of the classical lobule. None of these lesions match the zones of the acinar concept proposed by Rappaport. The concept of the hepatic lobule is essential to understand zonal lesions correctly.