Effects of ammonium metavanadate treatment upon macrophage glutathione redox cycle activity, superoxide production, and intracellular glutathione status.

Female B6C3F1 mice were given intraperitoneal injections of ammonium metavanadate (2.5 or 10 mg V/Kg), ammonium chloride, or sodium phosphate buffer every 3 days for 6 weeks. Resident peritoneal macrophages were harvested, lysed by freeze-thawing, and the resulting cytolysate was assayed for total protein content and enzyme activities of glutathione reductase, glutathione peroxidase, and glucose-6-phosphate dehydrogenase. In addition, peritoneal macrophages were assayed for superoxide production using nitroblue tetrazolium reduction, as well as for intracellular levels of oxidized and reduced glutathione. Exposure of mice to vanadium resulted in a dose-trend depression in the three macrophage enzyme activities as compared with the controls. Vanadium treatment resulted in a similar decrease in the production of superoxide anion, and an increase in levels of oxidized glutathione; however, the total glutathione pool (reduced plus oxidized forms) was not affected.