Abstract
The effect of osmotic shock was investigated mainly in the chloride cells (CCs) and rodlet cells (RCs) of gills, and RCs of intestine and kidney of the European sea bass Dicentrarchus labrax obtained from a farm in the northern Adriatic Sea. During the experiment, fish were abruptly transferred from sea water to a salinity of 15 (15 SW) or to fresh water (FW). Numeric variation and ultrastructural changes of both cell types were evaluated at 24, 48 and 96 h after the transfer to lower salinity levels, using light and transmission electron microscopy (TEM). Exposure to FW produced a significant increase ( P