目的 观察急性百草枯(PQ)中毒致肺损伤后血小板内皮细胞黏附分子-1(PECAM-1)水平的变化.方法 36只成年新西兰大白兔按随机数字表法分为PQ 8、16和32 mg/kg 3组,每组12只.胃管灌入20%PQ制模,7d后处死动物取肺组织行苏木素-伊红(HE)染色,观察肺组织病理改变,进行肺损伤评分,Masson染色鉴定肺纤维化程度,免疫组化半定量分析PECAM-1表达；将PECAM-1表达与肺损伤评分、肺纤维化程度进行相关分析.结果 随PQ中毒剂量增加,肺损伤评分、肺纤维化程度逐渐加重,肺PECAM-1表达逐渐下降；8、16、32 mg/kg PQ中毒组肺损伤评分(分)分别为8.33±1.03、9.83±1.17、11.50土1.38；肺纤维化程度分别为(31.09±2.05)%、(34.37±1.62)%、(36.54±0.44)%；PECAM-1表达分别为(20.31±0.70)%、(19.34±0.68)%、(18.37±0.46)%,组间两两比较差异均有统计学意义(P＜0.05或P＜0.01).Pearson相关分析显示,PECAM-1表达与肺损伤评分(r=-0.732,P=0.001)、肺纤维化程度(r=-0.779,P＜0.001)均呈明显负相关.结论 PQ中毒后,兔肺组织内PECAM-1表达明显下降,呈剂量依赖性,其与肺损伤程度、肺纤维化程度密切相关;PQ对PECAM-1的抑制是肺损伤发生发展的重要因素之一.%Objective To examine the changes in PECAM-I expression and its correlation to the level of pulmonary tissue injury in the lungs from rabbits exposed to acute PQ poisoning.Methods Three groups of New Zealand rabbits (12 each,randomly assigned) were treated with PQ at 8,16 and 32 mg/kg respectively through gavage.The animals were sacrificed 7 days after the poisoning and the upper lobe of their lungs collected for semi-quantitative microscopic evaluation of tissue injury,pulmonary fibrosis and the expression of PECAM-l after hematoxylin-eosin (HE),Masson,and immuno-histological staining.The correlation analysis was used for the relationship between the expression of PECAM-l and lung injury score or fibrosis of lung.Results The evaluation scores (demonstrated as mean+ standard deviation) in the three treatment groups were found to be (a) 8.33± 1.03,9.83士1.17 and 11.50士 1.38 for lung tissue injury,(b) (31.09士2.05)%,(34.37土1.62)% and (36.54士0.44)% for pulmonary fibrosis,and (c) (20.3 土 0.70)%,(19.34±0.68)% and (18.37土 0.46)% for PECAM-I expression.Statistically significant difference (P展开▼
