Physiological properties of eel haemoglobin: hypoxic acclimation, phosphate effects and multiplicity.

Unlike the whole body oxygen affinity, which adapts readily to environmental oxygen tensions, haemoglobins, prepared from normoxic- and hypoxic-accimated eels (Anguilla anguilla) show no adaptive changes in oxygenation properties or in multiplicity. Hypoxic acclimation is, howeveer, accompanied by a strong decrease in red cell nucleoside triphosphates, particularly guanosine triphospphate (GTP), which depresses oxygen affinity of the composite and component haemoglobins more strongly than does the concurring ATP. The effects of pH, temperature and salts on the oxygenation properties of the (isolated) haemoglobins are reported, discussed in relation to the varying environmetal conditions encountered by eels, and compared with data on American and Japanese eels (A. rostrata and A. juponica, respectively.