【摘要】 目的 :探讨早产鼠高氧肺损伤对其肺表面活性物质蛋白 ( SP)基因表达及肺表面活性物质 ( PS)代谢的影响。方法 :孕 2 1日 SD早产鼠仔 96只被随机分为高氧暴露组 ( 48只 ,常压高氧舱中 ,氧体积分数 >0 .95)和空气对照组 ( 48只 ,正常空气中 ) ,高氧暴露 7日后 ,采用逆转录聚合酶链反应 ( RT PCR)和双相薄层层析法( 2 D TL C)观察了 8只鼠肺 SP m RNA水平和 PS含量 ;对 2 0只鼠肺支气管肺泡灌洗液 ( BAL F) ,肺组织干重 /湿重和 1 0只鼠肺组织学变化也进行了分析。结果 :与空气对照组比较 ,高氧暴露组发展为肺损伤 ,肺组织有明显水肿、出血 ;BAL F中蛋白含量、细胞数和肺组织干重 /湿重明显增加 ( P均 <0 .0 5) ,而 PS含量未见明显变化 ( P均 >0 .0 5)。SP A m RNA和 SP B m RNA增加 ( P均 <0 .0 5) ,SP C m RNA变化未达统计学意义 ( P>0 .0 5)。结论 :早产鼠早期高氧肺损伤并不明显影响 PS含量的变化 ,但可导致 SP A m RNA和 SP B m RNA增加 ,这种基因表达的向上调节可能是机体的一种保护性应激反应。更多还原

【Abstract】 Objective:To investigate the effects of hyperoxia on surfactant metabolism and surfactant protein (SP) gene expression in a premature rat.Methods:SD rat litters were delivered prematurely at 21 days gestation by hysterotomy,and sacrificed after 7 days of continuous exposure to oxygen ( n= 48,oxygen>0 95) or room air ( n= 48).The mRNA levels of SP (SPA,SPB,SPC) were measured by reversetranscription polymerase chain reaction (RTPCR),and surfactant components were measured by twodimensional thinlayer chromatograph1 (2DTLC).In addition,lung samples from 10 rats were examined for histological changes,protein and cellular content of bronchoalveolar lavage fluid (BALF),lung wet/dry weight ratio were also determined in 20 rats lungs.Results:Animals exposed to oxygen developed severe lung damage,and their BALF also showed higher protein and cellular contents (all P <0 05) compared to controls.The quantity of surfactant component remained unchanged (all P >0 05).SPA mRNA and SPB mRNA levels in lung tissues were higher in the oxygenexposed rats (both P <0 05).Conclusions:This study suggested that early hyperoxic lung damage in premature rat does not affect surfactant components,but result in increase in SPA mRNA and SPB mRNA.The upregulation of SPA mRNA and SPB mRNA may be a protective response to oxygen toxicity.更多还原