氧自由基与小儿哮喘气道高反应性的关系

STUDY ON THE RELATIONSHIP BETWEEN OXYGEN FREE RADICAL AND AIR WAY HYPERRESPONSIVENESS IN ASTHMATIC CHILDREN

采用放免法和荧光法检测６４例哮喘发作期和缓解期患儿血中超氧化物歧化酶（ＳＯＤ）及脂质过氧化物（ＬＰＯ）含量，并与３４例健康儿童作对照。然后选取其中２８例患儿作支气管组织胺激发试验。结果：与对照组比较，患儿哮喘发作期中ＳＯＤ明显下降（Ｐ＜０．０ｌ），ＬＰＯ明显升高（Ｐ＜０．０１）；缓解期ＳＯＤ逐步回升，且有超出对照组水平的趋势，但无统计学意义（Ｐ＞０．０５），ＬＰ０基本恢复正常（Ｐ＞０．０５）。哮喘患儿无论是发作期抑或是缓解期，都有较高的气道反应性，且与ＳＯＤ呈明显负相关（ｒ＝一０．６４２９，Ｐ＜０．０１），而与ＬＰＯ呈正相关系（ｒ＝０．８７１ｇ，Ｐ＜０．０１）。提示哮喘发作期氧自由基（ＯＦＲ）明显升高，是促成气道高反应的主要因素之一，表明其在哮喘发病中起重要作用。

he blood content of superoxide dismatase(SOD)and lipidperoxides(LPO) was determined with RIA and fluorometric method respectively in 64 cases of asthmatic children with and without attack,and compared with that of 34 cases of normal subjects. Then,28 cases of asthmatic chil-dren were selected to take bronchial histamine provocation test.The results showed that SOD of asthmatic childrem with attack was apparently lower(P<0.0l)and LPO was higher(P<0.0l)when compared with that of normal subjects;In patients without attack, SOD increased gradually and had a trend to exceed the normal levels(P>0;05)and LPO almost returned to normal levels(P>0.05);In all patients studied a higher airway responsiveness was found.The AHR was nega-tively correlated with SOD(r=一0.6429,P<0,0l )and positively correlated with LPO(r=0. 8719, P<0.01). These results indicated that the marked increase of OFR in asthmatic patients with attack was one of the important factor in the development of AHR,suggesting its important role in the pathogenesis of asthma.