Compatible and counteracting solutes and the evolution of ion and osmoregulation in fishes

摘要: The evolution of ion and osmoregulation in fishes can be divided into three physiological stages. first stage is a strategy employed by extant hagfish involved reduction inorganic levels intracellularly through the use compatible organic solutes. During osmotic stress, concentration solutes changes to aid cell volume regulation, but both intracellular plasma may fluctuate. next step substitution permeable rapidly diffusing, nonmetabolizable solute (urea) for some other This utilized chondrichthians coelacanth. Specific methylamines are maintained cells extracellular fluids these organisms counteract adverse physicochemical effects urea. Species using this possess greater control during stress. Reduced relatively constant concentrations ions minim...