Some Effects of pH and Temperature upon Normal Human Red Cell Adenosine Triphosphate

Abstract

Red cell ATP levels were determined on the fresh blood of 58 normal subjects using an enzymic method. Values were obtained in the range 80 to 140 μmoles of ATP per 100 ml. of packed red cells. Conditions for obtaining reliable fresh blood ATP values are reported together with the effects of different anticoagulants. It was confirmed that red cell ATP is pH‐sensitive. Thus, at pH values below 7.6–7.7 (25° C.) it was stable but at values above this range it disappeared from the red cells. Kinetic studies of red cell ATP at different temperatures and pH values are described.

Factors Affecting the Autohaemolysis of Normal Human Red Cells and the Mechanism of Lysis in vitro

“…During the first 24-hr period o f incubation, endogenous glucose disappeared and red cell glycolysis ceased. In an effect which has been noted previously (Scott et al 1969) to be a conselquence of the high initial pH of defibrinated blood. Following the disappearance of glucose, red cell ATP content fell more steeply to reach a low and negligible level where it remained.…”

“…The consumption of endogenous glucose was accompanied by a fall in pH and by a slight increase in cell volume (Figure 8). Despite utilisation of glucose, the ATP content fell somewhat but it had previously been established (Scott et al 1969) that this was due to the high pH which usually obtains in defibrinated blood. Had adequate glucose been present throughout the period of incubation, then, after the initial fall, ATP would have been maintained, although at a reduced level.…”

“…Red cell adenosine tripkosphate (ATP). This nucleotide was measured with a standard assay kit (Boehringer & Soehne) the reliability of which had been established previously (Scott et al 1969). The results are expressed as ,umoles of ATP per 100. ml of packed red cells.…”