Fig. 3. Northern blots using total RNA (10 µg) showing the expression of AQP3 mRNA in the gill and intestine of freshwater (FW)- and 3-week seawater (SW)-acclimated yellow and silver eels. Each sample on the blot was taken from an individual fish such that N=6 for each group. RNA sizes (kb) were estimated from RNA standards (not shown). The gill blot autoradiograph was exposed for 3 h at -80°C and the intestine blot, 32 h at -80°C. The 7 kb band seen in the tissue blot in Fig. 2 was not visible on autoradiographs in this figure, although it was included in the quantification results (Fig. 4).