Morphological aspects of the liver of the freshwater turtlePhrynops geoffroanus Schweigger, 1812 (Testudines, Chelidae)

ABSTRACT

The objective was the morphological characterization of the liver of Phrynops geoffroanus, popularly knownas the freshwater turtle (cágado-de-barbicha in Portuguese), using six specimens from the Uberabinha Riverin Uberlândia, state of Minas Gerais, Brazil. The analyses involved anatomical and histological methods, andthe microscopic aspects were described after the histological preparation. Fragments of liver were fixed in10% formalin and absolute alcohol, embedded in paraffin, sectioned into four μm thick slices, and stainedwith HE, PAS, Gomori Trichrome and Reticulin. The liver of P. geoffroanus is a large light brown organspeckled with black spots, which represent melanin deposits. It is divided into four lobes, called the rightlateral, right medial, left lateral and left medial lobes. The hepatocytes in longitudinal section are similarto double cords surrounded by winding sinusoidal capillaries, polyhedral shaped, of varying sizes, with avacuolized aspect and with peripherally displaced nuclei. The cytoplasm is little eosinophilic and highly reactiveto PAS, suggesting abundant intracytoplasmatic glycogen. The hepatic parenchyma is supported by delicatereticular fibers surrounding hepatocytes and sinusoids. Large quantities of melanomacrophages are present inthe parenchyma and perisinusoidal spaces, mainly close to the portal spaces.