P1.89 Jan. 4 Na+/K+-2Cl-cotransporter Immunolocalization and Gene Expression in The Gills of The Golden Grey Mullet, Mugil auratus, Acclimated to The Brackish Water and Sea Water KHODABANDEH, Saber*; SHAHRIARI MOGHADDAM, Mohsen; Univ. of Tarbiat Modarres, Tehran, IRAN email@example.com
In euryhaline fish, Na+/K+-2Cl-cotransporter (NKCC) is important in maintaining a plasma osmolarity of ~300mOsm/Kg in an ambient seawater salinity of ~1000 mOsm/Kg. Immunolocalization, quantitive analysis of intensity and gene expression of NKCC were investigated in the Mugil auratus after exposure to brackish water (BW=12‰ salinity) and seawater (SW=36 ‰ salinity)for 7 days. NKCC immunoflurescence cells were detected in the mitochondria- rich cells of the gill in the both salinities. The results of quantification for NKCC show a significantly higher intensity in the mitochondria-rich cells in SW compared to BW. The NKCC gene expression was also significantly higer in SW than in BW(p<0.001). In conclusion, NKCC has its expression in osmoregulated when there is no further need of salt in SW fishes. The ability of golden grey mullet to high salinity tolerance, could be partially explained by the presence and a stronger role of NKCC in ions regulation by the gill mitochondria-rich cells.