Liver Regeneration and Structural Remodeling Following 2/3 Partial Hepatectomy: An Experimental investigation

Abstract

In liver structural units such as the classical lobule, portal lobule, acinus, Ekataksin’s cholehepaton, Matsumoto lobule/module, and Teutsch’s lobule/module, the number of portal triads typically exceeds that of hepatic vein tributaries. However, identifying these units in human and rodent livers is challenging because some regions do not clearly fit within any specific unit. This uncertainty complicates the evaluation of liver architecture after regeneration, particularly following hemihepatectomy, which is essential for both the remaining and transplanted livers as they regenerate

Methods: In this study, 24 adult male Wistar rats underwent two-thirds hepatectomy. Liver tissues were examined at 24, 48, and 96 hours, as well as at 1 and 2 weeks post-surgery, using histology, immunohistochemistry, and scanning electron microscopy of vascular corrosion casts. The resected liver sections served as controls, and morphometric analysis was used to compare the findings

Results: The study revealed:

• Enlargement and changes in the shape of hepatocytes across all zones of the hepatic lobule/acinus within two weeks post-surgery.
• Formation of atypical membrane protrusions and new intercellular connections between hepatocytes.
• Transformation of the vascular network, including altered shapes and sizes of existing structures, along with the development of new sinusoidal capillaries and venules.
• Hepatic vein tributaries outnumbering nearby portal veins.
• Early-stage hypertrophy and proliferation, followed by spatial transformations affecting cellular, vascular, and connective tissue components, resulting in structural remodeling of liver tissue.
• A tendency for classical lobules and acini to transition into Teutsch’s lobules/modules, characterized by the organic merging of sinusoidal compartments within these modules.

Conclusion: Liver tissue undergoes significant spatial reorganization following two-thirds hepatectomy. Although some of these observations are novel and not yet fully supported by current literature, further research is required for validation.