Iron toxicity to peritoneal macrophage due to alteration of Mitochondria by NO

The cytotoxic effect of iron was examined in peritoneal macrophage to determine contributing factors by iron injection to rat. Viability was reduced by 24% by the iron‐overload and by 30% by short‐term iron addition. Total iron was increased by 45% in the iron‐overloaded with remarkable elevation (9 to 14 fold) in the presence of FeSO4. Free calcium was also increased by 19% in control and 44% in iron‐overloaded group due to additional FeSO4. NO and MDA were increased by 40% and 136%, respectively, with significant reduction (37%) of NAD(P)H. RCR and cytochrome c oxidase activity were lowered approximately by 10% with reduction of mitochondrial membrane potential. Addition of iron was frequently associated with altered distribution of mitochondria of high membrane potential in the iron‐overloaded macrophage. These results suggest altered mitochondria with high NO and low NAD(P)H due to iron.