The blood oxygen binding properties of hypoxic Salmo gairdneri

Abstract

The blood oxygen binding properties of rainbow trout responded to environmental hypoxia (the oxygen saturation of water 30% at 11°C) in three ways. The quickest response was a moderate acidosis, leading to slightly lowered blood oxygen loading due to the Bohr effect. The second response, an increase of blood oxygen carrying capacity, was completed with 6 h from the onset of hypoxia. The speed of the response suggests that the formation of new haemoglobin played no practical role, the increase being caused either by a decrease of plasma volume or the liberation of erythrocytes from a storage organ. The slowest response, a 25% increase of the blood oxygen affinity within a week of hypoxia, was probably caused by the concurrent decrease of the erythrocyte ATP concentration from 4.45 to 2.51 μmol/ml erythrocytes. © 1980 Springer-Verlag.