Objective   To find out the mechanism of manganese induced neuro to xicity.The human dopamindrgic neurob lstoma cell SH-SY5Y was selected as test cell in the manganese cytotoxicity researches.

  Methods   The cells were treated by 0.00, 0.25, 0.50 and 0.75 mmol/L Mn, respectively.24 hours later, the cellular super oxide dismutase(SOD), gulathione peroxidase(GSH-Px), catalase(CAT)and glutathione(GSH)were detected.The microviscosity of membrane was detected.The single cell gel electrophoresis was used to test the DNA strand breakage degree.After 0.50 mmol/L Mn treated cells 24 h and 48 h cell apoptosis and cell cycle were analyzed by flow cytometer.

  Results   The activity of antioxidant enayme in Mn treated cells was lower than that of control group to some extent.The amount of MDA and the product of lipid peroxide in the treated cells were higher than those of control group The microviscosity of membr ane of the treated cells was increased.DNAstrand breakage degree demonstrated that the amount of comet cells was increased to some different extent in the treated cells.Moreover, there was positive correlation between the concentration of manganese and the damage degree.All Mn treated cells exhibited obvious apoptosis peaks, and the cell cycle was changed as well.The amount of Sphase cells was in creased.

  Conclusion   Manganese could make the cells hold the oxidative stress status and could induce cells damage.It might be one of manganese induced neurotoxicity mechanisms.