Morphological and Histological Study of Kidney in Juvenile Great Sturgeon (Huso huso) and Persian Sturgeon (Acipenser persicus)

Sturgeons are ancient and commercial fishes which posses’ primitive characteristics and due to their great inflections are able to live in both freshwater and marine environments. So their kidney has great ability for adaptation process. In order to find the structure and distribution of kidney nephrons in juvenile Huso huso and Acipensr persicus, sampling of head, body and caudal parts of kidney in fishes were carried out. Histological samples were dehydrated by routine methods and embedded in paraffin wax. They were sectioned by microtome and stained with H & E and PAS stain. The results revealed that the kidney of young Huso huso and Acipenser persicus consists of two lobes that are slender and long and is divided into three parts: a head, body and caudal part. Also, the kidney of sturgeons was consisted of: Glomeruls, Bowman s capsule, Proximal , (I & II), Distal and Collecting tubule. The renal corpuscles of sturgeons consist of a glomerulus and a glomerular (Bowman’s) capsule. The proximal tubules consisted of cuboidal cells with welldeveloped brush border. Two proximal tubule segments distinguished by the different heights of the cells and the brush border. The distal tubules have cuboidal epithelium without brush border. The collecting tubules lined with high cuboidal epithelium. Their nuclei are mainly spherical that are located in the central part of the cells. The kidney of H. huso and A. persicus was Y shape and distribution of different cells was not hemogene in all sections of kidney. The head of the kidney composed exclusively of hematopoietic tissue and islets of interrenal tissue. But, in the body and caudal part the amount of hematopoeitic tissue and interrenal glands were decreased and substituted by renal tubules and glomeruli. So, there are not any difference in kidney structure and nephrons morphology between A. persicus and H. huso.