CADMIUM-INDUCED PRODUCTION OF SUPEROXIDE ANION AND NITRIC-OXIDE, DNA SINGLE-STRAND BREAKS AND LACTATE-DEHYDROGENASE LEAKAGE IN J774A.1 CELL-CULTURES

The involvement of reactive oxygen species in the toxicity of cadmium (Cd) has been proposed. We have, therefore, examined the effects of th is cation on the production of superoxide anion and nitric oxide and D NA single strand breaks in J774A.1 macrophage cells in culture as well as the effects on lactate dehydrogenase (LDH) leakage and cell viabil ity. Following a 48-h incubation, over 2-fold increases in superoxide anion and nitric oxide (NO) production were observed at a Cd concentra tion of approximately 0.60 mu M, while a 50% decrease in viability was observed at this concentration. LDH leakage paralleled the superoxide anion and nitric oxide production. Concentration-dependent increases in DNA single strand breaks (SSB) were observed after incubation with Cd with a maximum increase occurring at a concentration of approximate ly 0.40 mu M. The results indicate that Cd is toxic to the J774A.1 cel l line, and support the hypothesis that the toxicity may be due at lea st in part to an oxidative stress induced by the production of reactiv e oxygen species following exposure to this cation.