Fig. 2. Elevated dietary salt intake increases the expression of genes involved in ion secretion in seawater. (A,B) The results of western blot analysis revealed a marked increase in Na⁺/K⁺-ATPase (NKA; band at 115 kDa) and Na⁺/K⁺/2Cl^- co-transporter (NKCC1; band at 160 kDa) protein in fish fed a high salt diet (filled bars; N=4 for each group). Blots were cropped for presentation purposes. (C) The levels of NKA, NKCC1 and cystic fibrosis membrane transmembrane conductance regulator (CFTR) mRNAs in salt-fed fish (N=14) were increased 5- to 15-fold relative to control fish (N=9). Asterisks in B and C indicate statistically significant difference from control values (P<0.05).