Distinctive features of hepatocytes in five small mammal species (insectivores and rodents): taxonomic versus ecological specificity

摘要

Morphometric parameters of hepatocytes have been studied in five small mammal species with different ecological specificity from two taxonomic groups: a surface-dwelling insectivore (the common shrew, Sorex araneus), a subterranean insectivore (the European mole, Talpa europaea), surface-dwelling rodents (the bank vole, Myodes glareolus and herb field mouse, Apodemus uralensis) and a subterranean rodent (the northern mole vole, Ellobius talpinus). The results show that the hepatocytes of the European mole differ markedly from those of all other species, being characterized by smaller size and nuclear area, low anisocytosis and anisokaryosis, the almost complete absence of binuclear cells and, on the other hand, high nuclear-cytoplasmic ratio and packing density. The common shrew differs from the European mole containing a relatively high proportion of binuclear hepatocytes, and the size of hepatocytes in this species is smaller than in rodents. Differences in the parameters of these cells between rodents are minimal or absent. The differences observed in the characteristics of hepatocytes between the above species cannot be explained solely by either taxonomic or ecological specificity. Comparative research involving a greater number of closely related species (at the levels of families and orders) is needed to reveal and evaluate the taxonomic and ecological specificity of hepatocytes in greater detail.