2 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...
Limited extracellular but complete intracellular acid-base regulation during sh...
Brauner, Colin John; Wang, Tobias; Wang, Yuxiang; Richards, Jeffrey G.; Gonzalez, Richard J.; Bernier, Nicholas J.; Xi, W.; Patrick, Marjorie L.Environmental hypercapnia induces a respiratory acidosis that is usually compensated within 24-96 h in freshwater fish. Water ionic composition has a large influence on both the rate and degree of pH recovery during hypercapnia. Waters of the Amazon are characteristically dilute in ions, which may have consequences for acid-base regulation during environmental hypercapnia in endemic fishes. The armoured catfish...