摘要
【目的】探讨高氧对新生大鼠肺组织超微结构的影响及其血管内皮生长因子(vascular endothelial growthfactor VEGF)蛋白表达的变化。【方法】新生SD大鼠48只随机分为高氧试验组和空气对照组,高氧试验组吸入95%以上高氧建立高氧肺损伤模型。采用透射电镜和免疫组化观察新生大鼠3、71、4 d肺组织超微结构和VEGF蛋白表达变化。【结果】吸入高氧3 d新生大鼠肺泡Ⅱ型上皮细胞(AEC-II)出现板层小体结构松散,部分血管内皮细胞肿胀,随着高氧吸入时间的延长,14 d时AEC-II、血管内皮细胞产生了致死性损害作用,出现了类似早产儿支气管肺发育不良的肺组织形态学特征。VEGF蛋白在高氧吸入3 d时出现降低,7 d明显降低,到14 d时进一步降低。【结论】持续高氧吸入可造成新生大鼠肺肺泡Ⅱ型上皮细胞和血管内皮细胞损害。高氧可抑制VEGF蛋白在新生大鼠肺内的表达,VEGF可能在新生鼠肺发育和高氧肺损伤发病机理中起重要作用。
[Objective] To explore the changes of ultrastructure of pulmonary and the role of vascular endothelial growth factor（VEGF） in neonatal rats with hyperoxia. [Methods] 48 spraqut Dawley neonatal rats were randomly divided into two groups（n=24）. The rats in experimental group inhaled 95% oxygen and the control group were fed in room air. The changs of ultrastructure of pulmonary type Ⅱ alveolar cell（AEC-Ⅱ） and vascular endothlial cell observed with electron microscope. The expres sion of VEGF protein in the lung was determined by using immunohistochemical methods. [Results] The structures of lamellar bodies in AEC-Ⅱ and pulmonary capillary endothelial cell swollen were partly damaged on the 3 d of hypenoxia induction, the normal structures of AEC-Ⅱ and pulmonary capillary endothelial cell were disappeared on 14 d, which shared morphologic similarities to human bronchopulmonary dysplasia. The expression level of VEGF protein was very lower than that of control group on the 7 d and to the lowest level on days 14. It was hardly to see the VEGF positive cells on 14 d. There was significient difference between the two groups on 3, 7 d（P〈0.05）, on 3,14 d （P〈0. 01）. [Conclusions] Hyperoxic exposure can cause lung injury of AEC- Ⅱ and vascular endothlial cell in neonatal rats. Hyperoxia decrease VEGF protein levels in lung of neonatal rats. VEGF might involve in the pathology of lung injury of hyperoxia.
出处
《中国儿童保健杂志》
CAS
2007年第6期629-631,共3页
Chinese Journal of Child Health Care
基金
陕西省科技攻关项目(2004K17G18)
关键词
高氧肺损伤
超微结构
管内皮生长因子
新生大鼠
lung injuy of hyperoxia
ultrastructure
vascular endotheial growth factor
neonatal rats
