عنوان مقاله [English]
Objective: Study of the microscopic structures of the liver and pancreas as two accessory digestive glands and their ducts in Acipenser stellatus.
Design: observational study.
Animals: Ten sturgeons, Acipenser stellatus and their liver and pancreas.
Procedure: Samples of liver and pancreas were taken and fixed in 10% formalin. The processing was done in Autotechnicon. Sections of 5 micron were stained by H & E method and studied under light microscope
Statistical analysis: Descriptive statistics.
Results: The liver capsule has a cuboidal epithelium and it’s lobulation is incomplete. Portal tract includes vessels and bile ducts, with columnar cells. Hepatocytes have many glycogen and lipid vacuols which were seen as bicellular plates, among them many sinusoids with hepatic macrophage cells were existed. Pancreas is composed of exocrine and endocrine parts. The former includes serous acini and their ducts with stratified columnar. Each has one or more centroacinar cells. The latter composed of langerhans islets with secretory polymorphic cells and many capillaries.
Conclusion: Microscopic structures of liver and pancreas in this species is more similar to the other fishes and even mammals. Both of them are acting as mixed glands with endocrine and exocrine functions. Hepatocytes have functions like the other species such as, glycogen and lipid deposits. protein synthesizing and neutralizing or transferring toxic materials. These are like the endocrine glands whereas bile secretion is considered as an exocrine function.
Pancreas as an accessory digestive gland has many acini with
secretory granules containing complementary digestive enzymes. which transfer via the ducts to the anterior intestine. The secretions of the langerhans cells as endocrine function enter the blood vessels directly. J. Foe. Vet. Med. Univ. Tehran. 57, 1: 19-23, 2002.