Fig. 5. Immunoblot of protein form opercular epithelia treated for different times with isotonic solution (control), hypotonic saline (Hypo) and hypertonic saline (Hyper). (A) Upper panel: p38 MAPK (38-40 kDa) was detected by antibody to any form of the protein. Lower panel: p38 MAPK detected by the antibody specific to the phosphorylated form of the protein. (B) Bar charts of quantitative scans averaged over three immunoblots where p38 MAPK phosphorylation was enhanced significantly (^*P<0.05, paired t-test compared to isotonic control level at the respective time, N=3) by hypotonic shock at 5 min, by hypertonic shock at 30 min and by both hypertonic and hypotonic shock in a second phase response at 60 min.