新生早产大鼠高氧暴露肺组织细胞色素C变化及其与肺细胞凋亡的关系  

Correlation between cytochrome C and the lung cell apoptosis in premature rats exposed to hyperoxia

作　　者：刘敬[1,2] 常立文[1] 卢红艳[1] 李文斌[1] 蔡成[1] 姜娜[1] 彭琼玲[1] 

机构地区：[1]华中科技大学同济医学院附属同济医院儿科,武汉430030 [2]首都医科大学附属北京妇产医院新生儿科

出　　处：《中华围产医学杂志》2007年第2期104-107,共4页Chinese Journal of Perinatal Medicine

基　　金：国家自然科学基金（30471824）

摘　　要：目的研究新生早产大鼠吸入高浓度氧（以下简称高氧）后肺组织细胞内细胞色素C（cytochrome C，Cytc）表达及分布的变化及其与肺细胞凋亡的关系，探讨Cytc变化在高氧肺损伤中的作用。方法将新生早产SD大鼠随机分为高氧组和空气组，高氧组暴露于浓度为85％左右的氧气中建立高氧肺损伤模型。在生后1、4、7、10、14d各组取材，分别用RT-PCR技术检测肺组织Cytc和caspase-9 mRNA表达，用免疫组化法检测Cytc蛋白分布，脱氧核糖核酸转移酶介导的X-dUTP缺口末端标记（terminal deoxynucleotid transferase-mediated X—dUTP nick end labeling，TUNEL）法检测肺细胞凋亡情况。结果生后第4天高氧组肺组织Cytc mRNA水平为0．5739±0．0228，第7天为1．1000±0．1050，均高于空气组（分别为0．4001±0．0383和0．6330±0．0740）（P均〈0．05）；高氧组肺组织caspase-9mRNA第4天为1．2975±0．0729，第7天为1．2012±0．0615，也分别高于空气组（分别为0．8428士0．0272和0．8086士0．0167）（P〈0．05）。生后各时间点肺组织Cytc免疫组化平均灰度值和肺组织细胞凋亡阳性率均高于空气组（P均＜0．01）。结论高氧暴露可致新生早产大鼠肺组织Cytc mRNA表达增加和Cytc分布变化，可能通过激活caspase-9进而导致肺细胞凋亡，从而导致高氧肺损伤。Objective The aim of this study was to explore the changes of the expression of cytochrome C （Cytc） mRNA and the redistribution of Cytc, also the influence of the changes of Cytc on the lung cell apoptosis in premature rats exposed to hyperoxia. Methods The neonatal premature rats were divided randomly into hyperoxic group and air group. The neonatal premature rats in hyperoxic group were exposed to 85 % oxygen after birth to establish hyperoxic lung injury model, while air group were in room air. At 1^st , 4^th , 7^th , 10^th and 14^th day after birth, the expression of Cytc mRNA and caspase-9 mRNA in lung tissue was detected by using reverse transcription polymerase chain reaction （RT-PCR）. Immunohistochemistry was done to observe the redistribution of Cytc peptide, and lung cell apoptosis were observed by terminal deoxynucleotid transferase-mediated X-dUTP nick end labeling （TUNEL）. Results Cytc mRNA in hyperoxie group at 4^th and 7^th（0. 5739±0. 0228 and 1. 1000±0. 1050） were higher than air group （0.4001±0.0383 and 0.6330±0.0740） （P〈0.05）. The level of caspase-9 mRNA in hyperoxic group at 4^th and 7^th（1. 2975±0. 0729 and 1. 2012±0. 0615） were higher than air group too （0. 8428±0. 0272 and 0. 8086±0. 0167） （P〈0.05）. The Cytc redistribution to cytoplasm and the number of lung cell apoptosis were higher than air group at all time points （P〈0.01）. Conclusions The changes of the expression of Cytc mRNA and the redistribution of Cytc may result in lung cell apoptosis in neonatal premature rats exposed to high concentration of oxygen by activating the caspase-9.

关 键 词：大鼠 婴儿 早产 高氧症 细胞色素C类 半胱氨酸天冬氨酸蛋白酶 细胞凋亡 

分 类 号：R722[医药卫生—儿科]