3 documents found, page 1 of 1
Mechanisms of ion transport in Potamotrygon, a stenohaline freshwater elasmobra...
Wood, Chris M.; Matsuo, Aline Y.O.; Gonzalez, Richard J.; Wilson, Rod W.; Patrick, Marjorie L.; Val, Adalberto LuisStingrays of the family Potamotrygonidae are the only stenohaline freshwater elasmobranchs. Potomotrygon sp. collected from the ion-poor blackwaters ([Na+], [Cl-] and [Ca2+]=10-30μmoll-1, pH6.1) of the Rio Negro, Amazonas, Brazil, were ammoniotelic (91% ammonia-N, 9% urea-N excretion) and exhibited blood chemistry (Na+, Cl-, urea, ammonia and glucose levels and osmolality) typical of freshwater teleosts. Unidir...
Low pH and calcium effects on net Na+ and K+ fluxes in two catfish species from...
Matsuo, Aline Y.O.; Val, Adalberto LuisThe present study analyzes Na+ and K+ disturbances caused by low pH in two catfish species from the Amazon River. Corydoras adolfoi inhabits ion-poor, black-stained, low pH (3.5-4.0) waters, while C. schwartzi is native to ion-rich waters at circumneutral pH. Fish were exposed to pH 3.5 Ca2+-free, and Ca2+-enriched (∼500 μmol/l) water to determine the protective effects of calcium. Net Na+ and K+ fluxes were me...
Dietary tissue cadmium accumulation in an amazonian teleost (Tambaqui, Colossom...
Matsuo, Aline Y.O.; Val, Adalberto LuisUnderstanding the effects of metal contamination in the Amazon basin is important because of the potential impact on this region of high biodiversity. In addition, the significance of fish as the primary source of protein for the local human population (living either alongside the Amazon River or in the city of Manaus) highlights the need for information on the metal transfer through the food chain. Bioaccumula...