15 minutes at 4° c. Supernatant erythrocyte lysate collected was analyzed.
The Cayman glutathione peroxidase assay kit was used to measure all the glutathione-dependent perox-idases in plasma and erythrocyte lysate indirectly by a coupled reaction with glutathione reductase (GR). The oxidized glutathione produced upon reduction of hydroperoxide by GPx was recycled to its reduced state by GR and NADPH. The oxidation of NADPH to NADP¯ was directly proportional to the GPx activity in the sample (Ursini et al., 1985).