Tert-butyl hydroperoxide decreases GSH and total free glutathione (GSH+2GSSG) contents of acini from lactating mammary glands. The decrease in total free glutathione can be explained by an increase in mixed disulfide formation and by excretion of GSS G to the extracellular medium, and subsequent degradation catalyzed by gamma-glutamyl transpeptidase. Low concentrations of glucose prevented the changes in glutathione levels induced by the peroxide. In the presence of extracellular ATP, glucose did not prevent these changes. However, incubations with the peroxide, did not alter the rate of other metabolic pathways by acini.
Abbreviations used GSH, Reduced glutathione; GSSG, Glutathione disulfide; GSSR, Glutathione mixed disulfide; GGT, Gamma-glutamyl transpaptidase; tbOOH, Tert-butyl hydroperoxide