Na+/K+-ATPase α1 mRNA expression in the gill and rectal gland of the Atlantic stingray Dasyatis sabina following acclimation to increased salinity

摘要

BackgroundThe salt-secreting rectal gland plays a major role in elasmobranch osmoregulation, facilitating ion balance in hyperosmotic environments in a manner analogous to the teleost gill. Several studies have examined the central role of the sodium pump Na⁺/K⁺-ATPase in osmoregulatory tissues of euryhaline elasmobranch species, including regulation of Na⁺/K⁺-ATPase activity and abundance in response to salinity acclimation. However, while the transcriptional regulation of Na⁺/K⁺-ATPase in the teleost gill has been well documented the potential for mRNA regulation to facilitate rectal gland plasticity during salinity acclimation in elasmobranchs has not been examined. Therefore, in this study we acclimated Atlantic stingrays, Dasyatis sabina (Lesueur) from 11 to 34 ppt salinity over 3 days, and examined changes in plasma components as well as gill and rectal gland Na⁺/K⁺-ATPase α1 (atp1a1) mRNA expression.