Sea bream liver : histological and ultrastructure studies (ii)‎ biliary system and hepatopancreas

Abstract EN

The liver was covered by a thin fibrous connective tissue capsule, and a single layer of mesothelial cells.

The parenchyma of the liver was not divided into lobules.

The biliary channels were dispersed throughout the parenchyma.

The biliary tree was formed of canaliculi, preductules, ductules and ducts.

The bile canaliculi were formed by the apposition of 2-3 hepatocytes and the plasmatic membrane at this level projected numerous microvilli into the lumen.

Adjacent cells were joined by apparent tight junctions, followed by desmosomes.

Bile ductules were lined by 2-3 cuboidal cells with rounded nuclei and prominent nucleoli, its outer contour was surrounded by dark stained cell with flat nucleus.

These cells were attached by apparent tight junctions, desmosomes and interdigitations.

Additionally they were joined to the hepatocytcs basally by desmosomes.

Few short microvilli projected into the lumen.

Bile ducts showed a clear basal lamina.

The small sized duct was lined by 4-6 cuboidal cells, with spherical vesicular nuclei, prominent nucleoli and with clear apical brush border.

It was surrounded by connective tissue.

Ultrastructurally, the bile duct was encircled by fibrocytes and myocytes, up to 4 layers.

Few microvilli were observed on the apical border.

The large bile ducts were lined by more than six cells and had a much wider lumen than the smaller ducts.

Its lining was columnar cells with slightly elongated basal nuclei.

Dark stained nuclei of migratory cells were observed in the epithelium of large bile duct.

Rodlet cells were found among the biliary epithelial cells.The large bile duct was surrounded by abundant fibrous connective tissue formed mainly of collagen fibers and few reticular fibers.

The bile duct had apical brush border which reacted positively with PAS