Endogenous glutathione and catalase protect cultured rat astrocytes from the iron-mediated toxicity of hydrogen peroxide

Abstract

Primary astrocyte cultures from rat brain were exposed to hydrogen peroxide (H2O2) to investigate peroxide toxicity and clearance by astrocytes. After bolus application of H2O2 (100 μM), the peroxide was eliminated from the incubation medium following first-order kinetics with a half-time of approximately 4 min. The rate of peroxide detoxification was significantly slowed by pre-incubating the cells with the glutathione synthesis inhibitor buthionine sulfoximine (BSO), or the catalase inhibitor 3-amino-1,2,4-triazole (3AT), and was retarded further when both treatments were combined. H2O2 application killed a small proportion of cells, as indicated by the levels of the cytosolic enzyme lacta..