Oxidative stress-mediated neurotoxicity of cadmium

Young albino rats were administered cadmium i.p. (0.4 mg/kg body weight) for a period of 30 days and membrane fluidity, intracellular calcium level, MDA level, phospholipids, (phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol, phosphatidylserine and sphingomyelin) and reduced glutathione were studied in olfactory bulb, cerebellum and rest of brain. A decrease in membrane fluidity was observed in all the brain regions studied, maximum being in olfactory bulb (21%). Intracellular calcium (Ca++)(i) level was increased significantly in olfactory bulb (150%) followed by rest of brain (98%) and cerebellum (71%) in Cd-exposed rats in comparison with controls. A significant decrease in phosphatidylcholine (27%) and phosphatidylethanolamine (22%) was observed in olfactory bulb, while other phospholipids remained unaffected. TEA reactivity was increased in olfactory bulb (77%), cerebellum (35%) and rest of brain (27%). Reduced glutathione level was also decreased in different brain regions. The results suggest that the effect of cadmium in brain is region-specific and most pronounced in olfactory bulb.