Changes in Chloride Cell Abundance, Na+, K+-ATPase Immunolocalization and Activity in the Gills of Golden Grey Mullet, Liza aurata, Fry During Adaptation to Differend Salinities

Objective: changes in chloride cell abundance, na+, k+-atpase immunolocalizationand activity were investigated in the gills of the golden grey mullet, liza aurata, fry acclimatedto freshwater (fw) and different salinities (12‰, 36‰ and 46‰).materials and methods: na+, k+-atpase localization was performed through immunofluorescencelight microscopy using a mouse monoclonal antibody iggل5. quantitiveanalysis of na+, k+-atpase intensity was analyzed using optima’s version 6.51 imageanalysis software (media cybernetics, silver spring, md, usa).results: in fw, the fluorescent cells (chloride cells) were observed on the epitheliaof filaments (mainly in inter-lamellar regions) and on the lamellae. following transferto 12‰ salinity, the abundance of na+, k+-atpase immunofluorescence cells on thefilaments decreased 1.7-fold, and no immunofluorescence cells were detected on thelamellae. samples from 36‰ and 46‰ salinity showed a high density of chloride cellson the epithelia of filaments, and a few cells on the lamellae. na+, k+-atpase intensitydid not change significantly with an increase in salinity from 36‰ to 46‰ but it wassignificantly higher (p>0.05) in the fw compared to 12‰ salinity. there was no significantdifference between gill na+, k+-atpase activity in fw and 12‰ salinity, but it wassignificantly higher (p>0.05) in the fish acclimated to 36‰ and 46‰ salinity (3.3- and5.1-fold) compared to 12‰.conclusion: the capability of l. aurata fry to change the number and size of gill chloridecells, as well as their activities indicate the high degree of adaptability of this fishto a wide range of salinity.