ABSTRACT
Red cells contain only cytoplasmic CuZN SOD which can generally be measured by any of the methods described in this volume. Most commonly, either xanthine and xanthine oxidase, or riboflavin and light, are used to generate superoxide, which is detected by its reaction with cytochrome c or nitroblue tetrazolium (NBT). 1 - 6 An alternative is to measure the rate of disappearance of potassium superoxide at pH 10. This assay, which is described in detail by Marklund elsewhere in this book, has the advantage of allowing the use of whole hemolysate, whereas with most other methods, it is necessary to make a chloroform-ethanol extract to remove hemoglobin. Radioimmunoassay can also be used for measuring red cell SOD. In this chapter. I shall describe the preparation of chloroform-ethanol extracts of red cells and the determination of SOD activity by the riboflavin/NBT method. 2 , 3 Methods using xanthine and xanthine oxidase or cytochrome c, which can also be used with red cell chloroform-ethanol extracts, are also described in References 1 and 2.
