Histological study of liver in Dhub lizard Uromastyx aegyptius microlepis (Blanford, ۱۸۷۴) during the period of hibernation

The Iraqi dhub-lizard enters the hibernation when the temperature decreases in the winter. During this period, light microscopic analysis showed that the hepatic tissue is surrounded by a thin capsule composed mainly of collagen fibres. Trabeculae extended from this capsule towards the parenchyma were restricted to the subcapsular region and the liver tissue had no clear lobulation.  Hepatocytes were arranged into one or two cell thick cords or acini contained three to five cells.  Hepatocytes were polyhedral, oval and pyramidal in shape, and some of these cells demonstrated degenerative changes. Sinusoids appeared either as narrow irregular shape channels separating the hepatic cords with two layers of cells or wide channels separating the cords with one layer of cells. At the beginning of hibernation, application of the PAS technique revealed that glycogen granules spread heterogeneously within the hepatocyte cytoplasm and appeared dark pink in colour while at the end of hibernation these granules decreased in quantity and appeared light pink in colour. Large quantities of various-sized melano-macrophage aggregations were present in the liver tissue. The liver contained a very dense vascular system represented by the vessels of portal areas, the central veins, and the presence of hematopoietic tissue.

کلیدواژه ها:

Liver ، Dhub lizard ، Uromastyx aegyptius microlepis ، Hibernation