Oxidation damage of airborne fine particulate matter on brains of rats

  Objective   To investigate the toxicological mechanism of airborne fine particulate(PM_2.5)on brains of rats.

  Methods   32 male wistar rats were randomly divided into PM_2.5 exposure groups at different concentration(1.5, 7.5, 37.5 mg/kg)and control group instilled with physiological saline.Rats were killed 24 h after instillation, and the levels of thiobar bituric acid reactive substance(TBARS), Glutathione(GSH)and activities of superoxide dismutase(SOD), Glutathione peroxidase(GSH-Px), Catalase(CAT)were measured.

  Results   The activities of SOD and CAT decreased with PM_2.5 concentration in a dose depenent manner(P < 0.05).PM_2.5 instillation at 37.5 mg/kg caused statistically significant decrease of GSH level.(P < 0.05).The changes of GSH-Px activities and TBARS levels at all concentration were not statistically significent in comparison with control group.SOD/TBARS decreased significantly at all concentrations, and TBARS/GSH-Px increased significently at 37.5 mg/kg concentration(P < 0.05).

  Conclusion   PM_2.5 could cause oxidative damage to brains of rats.It was a neural toxin.