Effects of inhalable particle matters on airway inflammation of rats

  Objective   In order to study the mechanism of the airway inflammation induced by the inhalable particle matter (PM₁₀), the toxicity effects of PM₁₀ collected from Beijing urban area on rat s airway were assessed by intratracheal instillation.

  Methods   PM₁₀ was collected by MODEL-120A in Beijing urban areas.After rats were treated by PM₁₀ twice, samples were obtained.

  Results   The total number of inflammatory cells, the concentration or activities of acid phosphatase(ACP), alkaline phosphatase(AKP) and malondiadehyde(MDA)in BALF in PM1-0treated groups were increased in a dose-respondent manner, while glutathion-peroxidase (GSH-Px)was decreased compared with control group.The activities of ACP and GSH-Px in lung homogenate of the highest doses group were significantly different from that in control group.The results of histopathological analysis indicated that PM₁₀ can cause airway injury and pathological changes, such as the damage of alveolar septum, bronchial epithelium in a dose dependent way.The infiltration of inflammatory cells in lung matrix, especially eosinophilia was observed.These studies suggested that PM₁₀ had free radical activity and caused lung inflammation and epithelial injury.

  Conclusion   ACP and GSH-PX may be considered as sensitive indicatior of toxic effect of PM₁₀ on rat s airway inflammation.