EXPERIENCES WITH RED-CELL ENZYME ASSAYS

The red cell is continually exposed to oxidative challenge, both physiological and non-physiological. Specific antioxidant defence systems have evolved and, under normal conditions, protect the red cell against oxidative damage. However. If an additional extraneous oxidative challenge is presented to the red cell, e.g. oxidant drugs, the reducing potential of these defence mechanisms will be stressed, and if overwhelmed, the red cell will be damaged and consequent haemolysis may occur. Many red cell enzymes play an important role in the complex defence mechanism, and changes in the activities of these protective enzymes may precede overt haemolysis. The monitoring of these enzyme levels is of particular interest in the development of compounds with oxidative potential. Methods have been investigated to assay such enzymes in the hope of detecting uncompensated oxidative stress prior to irreversible damage.