中文摘要：

[目的]利用动物实验，比较上海二城区各个季节大气细颗粒物（PM2.5）对大鼠肺部炎症指标的影响。[方法]分别在上海市宝山区、徐汇区采集两个社区4个季节的大气中PM2.5。每社区每个季节PM2.5，设低、中、高剂量组（分别为1．6、8．0、40．0mg／kg体质量），另设生理盐水对照组，每组6只sD大鼠。采用气管滴注的方式染毒，连续染毒3d。最后一次气管滴注24h后，收集肺泡灌洗液进行细胞计数，测定肺泡灌洗液中总蛋白、乳酸脱氢酶、白介素-6、肿瘤坏死因子-α的变化。[结果]肺泡灌洗液中各指标均呈现剂量-效应趋势。不同地区比较：宝山PM2.5对上述指标的影响在高剂量组均明显强于徐汇PM2.5（P〈0．05）。不同季节比较：宝山高剂量组乳酸脱氢酶、白介素-6的含量春季明显大于夏、秋两季（P〈0．05），冬季明显大于秋季（P〈0．05），而在徐汇高剂量组秋季明显低于其他季节（P〈0．05）。宝山高剂量组白介素-6在春、冬两季明显高于夏、秋两季（P〈0．05），而在徐汇高剂量组春季明显高于秋季（P〈0．05）。肿瘤坏死因子-α含量在宝山中、高剂量组春季明显高于秋季（P〈0．05），而在徐汇高剂量组春、冬两季明显高于夏、秋两季（P〈0．05）。在高剂量组宝山和徐汇春季PM2.5致肺泡灌洗液细胞总数增加明显高于秋季（P〈0．05）。[结论]宝山钢铁工业区PM2.5对大鼠肺部炎性损伤强于徐汇交通区PM2.5,凡并存在一定的季节差异性。

英文摘要：

[ Objective ] To compare the toxicity of fine particulate matters （PM2.5）-in each season collected from different districts of Shanghai through an animal experiment. [ Methods ] PM2.5 was sampled from Baoshan and Xuhui districts of Shanghai in each season. Sprague Dawley rats were divided into three PM2.5 dosage groups （1.6, 8.0, and 40.0mg/kg body weight） and one saline control group of six rats each. Each group received intratracheal instillation once per day for three consecutive days. Twenty-four hours after the last exposure, bronchoalveolar lavage fluid （BALF） were collected and analyzed for ingredient changes including lactate dehydrogenase （LDH）, total protein （TP）, tumor necrosis factor α （TNF-α）, interleukin-6 （IL-6）, and cell number. [ Results ] The concentrations of all parameters increased in a dose-dependent manner. The effect was more strongly driven by high-dose PM2.5 exposure from Baoshan district than that from Xuhui district （P〈 0.05）. For the Baoshan high dose groups, the levels of LDH were higher after spring particle exposure than after summer and autumn particle exposures （P〈0.05）, and were also higher after winter particle exposure than after autumn particle exposure （P〈 0.05）. In contrast, for the Xuhui high dose groups, the lowest levels of LDH were found after autumn particle exposure （P〈 0.05）. Baoshan spring and winter PM2.5 exposure at high doses exhibited stronger toxic effects in producing IL-6 than summer and autumn particle exposure did （P〈0.05）, while Xuhui spring PM2.5 exposure at high dose produced more IL-6 than autumn exposure did （P〈0.05）. Baoshan spring PM2.5 exposure at middle and high doses exhibited the strongest toxic effects in producing TNF-α （P〈 0.05）, while Xuhui spring and winter PME.5 exposure at high dose produced more TNF-α than summer and autumn exposure did （P〈0.05）. The cell number increased more significantly in spring than in autumn in both Baoshan and Xuhui districts （P〈 0