大鼠哮喘模型肺组织血红素氧合酶-1蛋白及基因表达

目的 探讨大鼠哮喘模型肺组织血红素氧合酶-1(HO-1)蛋白及基因表达特点以及其与HO-1的活性之间的相关性.方法 清洁级雄性SD大鼠20只,随机分为对照组和哮喘组,每组10只.测定全血碳氧血红蛋白(COHb)的百分比含量;计算肺泡灌洗液(BALF)沉渣中细胞总数和分类;计数气道壁中浸润的炎性细胞数;用免疫组织化学染色法观察HO-1在哮喘大鼠肺组织的表达;用RT-PCR方法 检测哮喘大鼠肺组织HO-1基因表达.结果 HO-1阳性细胞主要定位于支气管上皮细胞及黏膜下巨噬细胞,气道平滑肌细胞偶有表达.2组表达HO-1的阳性细胞百分比分别为(5.03±1.22)%和(27.14±4.68)%;2组HO-1基因表达光密度比值分别为(0.32±0.05),(0.68±0.02);2组全血COHb的百分比含量分别为(0.45±0.35),(3.89±1.15);哮喘组HO-1蛋白、基因的表达水平以及全血COHb的百分比含量均显著高于正常组(P＜0.01).HO-1蛋白表达水平、基因表达水平与全血COHb的百分比含量均呈正相关(r=0.897,0.971,P＜0.01).结论 哮喘大鼠的肺组织HO-1蛋白基因表达水平显著增加,且反应HO-1活性的全血COHb的百分比含量亦显著增加,提示HO-1可能参与了哮喘的发病过程.

Expression and significance of heine oxygenase-1 in the lung tissue of asthmatic rat

Objective To investigate the protein and mRNA expression of HO-1 in the lung tissue of asthmatic rat and the correlation between the percentage of blood carbon monoxide Hb(COHb)and the expressions of HO-1 in the lung tissue of asthmatic rat.Methods Twenty Sprague-Dawley(SD)male rats were randomly divided into 2 groups,control group and asthma group.Each group had 10 rats.The assessment of the percentage content of blood carbon monoxide Hb(COHb)wag performed.The total cell number and differentiation cell numbers in bronchoalveolar lavge fluid(BALF)and the inflammatory cells of airway wall were counted,the protein expressions of HO-1 in airway wall wag detected with immunohistochemistry technique.and the mRNA expressions of HO-1 in airway wall was detected with RTPCR.Results The expression of HO-1 was mainly located in airway epithelium and macrophage.The percentage of the cells in which protein of HO-1was expressed were(5.03±1.22)%,(27.14±4.68)%in two groups.The optical densities of mRNA expression of HO-1 were 0.323±0.05,0.68±0.02.The percent content of blood carbon monoxide Hb(COHb)were(0.45±0.35)%,(3.89±1.15)%.The protein and mRNA expressions of HO-1 and the percent content of COHb in asthmatic group were higher than those of the control group (P＜0.01 respectively).There was a significant positive correlation araong the protein expression of HO-1 in airway wall and the percent content of COHb(r=0.971,P＜0.001),mRNA expressions of HO-1 in lung tissue and the percent content of COI-Ib(r=0.897,P＜0.001).Conclusion The protein and mRNA expressions of HO-1 in the lung tissue,and the percent of COHb in blood were significantly mcreaged in asthmatic rat,which suggested HO-1 may play a significant role in the pathogenesis of asthma.