Environmental induction of Na + transporter affinity in Atlantic salmon embryos

• Published in: Journal of Fish Biology
• Main Author: McWilliams, P. G.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1993
• Subjects: Atlantic salmon; Salmo salar
• Online Access: http://dx.doi.org/10.1111/j.1095-8649.1993.tb00310.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1095-8649.1993.tb00310.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1095-8649.1993.tb00310.x

Atlantic salmon ( Salmo salar L.) alevins hatched from eggs transferred from high‐ to low‐Na water at 250° days, before the onset of the phase of increasing whole egg sodium content (at ∼380°days), showed a significantly reduced K m for Na + transport, whereas transfer at 400° days did not produce any change in K m . Alevins hatched from eggs given acid shocks of 1, 3, 7 or 14 days duration initiated at 250 or 400° days showed no significant changes in Na + transporter K m . Extended acid exposure (38 days) from 250°days to hatching resulted in a slight lowering of K m (P<0.05). A 24‐day acid exposure from 400°days to hatching had no effect on Na + transporter K m . Alevins hatched from eggs incubated throughout in acidified water had a significantly reduced K m compared to controls (P<0.01). The timing and duration of periods of Na depletion of eggs is considered with respect to environmental induction of increased Na transporter affinity in teleost embryos as a mechanism of long‐term physiological adaptation to the gradual acidification of natural waters.