22 research outputs found
Recruitment of amphidromous sleepers Eleotris acanthopoma, Eleotris melanosoma, and Eleotris fusca into the Teima River, Okinawa Island
Response of branchial Na+/K+ ATPase to changes in ambient temperature in Atlantic cod (Gadus morhua) and whiting (Merlangius merlangus)
Distribution, Abundance, and Habitat Characterization of the Saltmarsh Topminnow, Fundulus jenkinsi (Everman 1892)
Time course of osmotic adaptation and gill energetics of rainbow trout (Salmo gairdneri R.) following abrupt changes in external salinity
Metabolic responses to salinity changes in the subantarctic notothenioid teleost Eleginops maclovinus
Eleginops maclovinus is an endemic, subantarctic Notothenioidei species. This study examined the influence of different environmental salinities (5, 15, and 45 psu; and 32 psu as a control) on energy metabolism in E. maclovinus over a period of 14 days. Metabolite contents and enzymatic activities related to carbohydrate, amino acid, and lipid metabolisms were evaluated in metabolic (liver) and osmoregulatory (gill and kidney) tissues. At extreme salinities (5 and 45 psu), the liver showed a high consumption of energy reserves, mainly as amino acids and carbohydrates. Carbohydrate metabolism in the gills did not change under different salinities, but increased lactate levels were found, suggesting that this tissue may use lactate as an energy substrate. Amino acid metabolism in the gills decreased at 5 psu but increased at 45 psu, and lipid metabolism increased at 5 and 15 psu during the first days of the trial, indicating a possible use of lipids as energy. Kidney carbohydrate catabolism and amino acid metabolism increased after 14 days at 45 psu, while lipid metabolism did not vary in relation to salinity changes. Together, these results suggest that the liver is most affected by salinity changes, probably due to its role as a supplier of energetic substrates. The gills and kidney, osmoregulatory tissues, maintained their energy metabolism levels with minor modifications. In conclusion, E. maclovinus exhibits metabolic adjustments to adapt to different salinities, showing the best responses in isosmotic environmental salinities