Dose-dependent effect of recombinant CHH-B1 on osmoregulatory capacity and Na+/K+-ATPase expression in bilaterally eyestalk-ablated shrimp Litopenaeus vannamei

Osmoregulation in crustaceans is under neuroendocrine control by the crustacean hyperglycemic hormones (CHHs), which modify water and ion concentrations in diverse species. Previous studies done by our group suggested that CHH variant B1 (CHH-B1) has effects on the osmoregulatory responses of the Pacific white shrimp Litopenaeus vannamei. For a better understanding of the molecular action mechanisms of CHH-B1 in osmoregulation, in this work, we established the dose-dependent effect of recombinant CHH-B1 on the gene expression of Na+/K+-ATPase (NKA) in gills, in contrast to changes in the osmoregulatory capacity (OC) of bilaterally eyestalk-ablated shrimp under hyper-osmotic conditions. The results indicate that CHH-B1 regulates the OC of shrimp during hypo-regulation by modulating Na+/K+-ATPase at a transcriptional level. Our results suggest that CHH has a direct participation in the control of osmo-ionic regulation mechanisms, not only in L. vannamei but in crustaceans in general.