Effect of salinity on mitochondria of chloride cells in gill of juvenile's grouper (Epinephelus coioides)

For determining and changes of chloride cells, in gill of juvenile's grouper histomorph-ology were used during adaptation in two months. After fixation, specimens were dehyderated through a graded ethanol series and embedded in paraffin. Then, the serial sections of 5 m were mounted onto glass slides. The slides were stained by applying H & E and TEM methods for histological examination. Histological changes were studied by light microscopy. Then, in autumn, fishes directly transferred from salinity 40ppt which is normal for the Persian Gulf water to other treatment (10ppt, 20ppt, 60ppt). Results of light microscopic study showed during 15 days, numbers change of chloride cells and mitochondria were significant in different salinity.