Study on rat pulmonary toxicity induced by PM2.5 in atmosphere of Lanzhou city

  Objective   To study acute injury and mechanism of rats respiratory tract induced by PM_2.5.

  Methods   Wistar rats weighing between 180~220 g were randolmly divided into five groups including blank control group, saline control group, three level PM_2.5(high, middle and low)groups.Three level PM_2.5 groups were instilled intratracheally with 0.5 ml suspensions of PM_2.5 and saline control group were instilled intratracheally with 0.5 ml saline.After 12 days rats were killed, pulmonary pathological injury and bronchoalveolar lavage flluid(BALF)of all rats were later examined, including the level of lactate dehy drogenase(LDH), alkaline phosphatase(AKP), acidic phosphatase(ACP), albumin(ALB), immunoglobuli G(IgG), immunoglobuli A(IgA).

  Results   The amount of LDH, AKP, ACP, ALB, IgG, IgA in exposed groups were significantly higher than those in saline control, but no evident difference between blank control and saline control(P < 0.05).Inflammatory changes including neutrophil and monocyte, lymphocyte hyperplasia were observed on pulmonary pathological slide in a dose denpendent way.

  Conclusion   PM_2.5 have acute toxic effects on rat pulmonary cells and membrane tissues, also bring sapimmune response and macosal immune response.