蛋白激酶R样内质网激酶的磷酸化对缺氧缺血性脑损伤新生大鼠脑神经细胞凋亡的影响  

The role of phosphorylated protein kinase R-like ER kinase in brain tissue of hypoxic-ischemic neonatal rats and the following effect on neuronic apoptosis

作　　者：顾卉[1] 纪莲[1] 黄天楚[1] 梅妍[2] 袁正伟[1] 

机构地区：[1]中国医科大学附属盛京医院卫生部小儿先天畸形重点实验室,沈阳110004 [2]武汉大学口腔医学院,430000

出　　处：《中国小儿急救医学》2015年第5期316-319,共4页Chinese Pediatric Emergency Medicine

基　　金：国家自然科学基金（31201053）

摘　　要：目的研究蛋白激酶R样内质网激酶（proteinkinaseR—likeERkinase，PERK）的磷酸化及其下游的C／EBP同源蛋白（C／EBPhomologousprotein，CHOP）的表达在缺氧缺血性脑损伤（hypoxic—ischemicbraindamage，HIBD）中的作用和机制。方法60只新生7日龄SD大鼠分为假手术组和HIBD组，每组各30只，每组又按照手术0h，6h和24h分为3个亚组，每组10只。采用流式细胞仪检测脑细胞凋亡情况，并用Westernblot方法测定脑组织中磷酸化的PERK及CHOP表达水平。结果（1）HIBD6h出现典型的凋亡细胞峰，细胞凋亡率为（2．17±0．19）％。HIBD24h凋亡峰更为明显，细胞凋亡率达到（13．42±0．83）％，与假手术组（0．57±0．06）％相比，差异有统计学意义（P〈0．01）。（2）假手术组与HIBD0h大鼠脑组织中磷酸化的PERK和CHOP表达水平较低，在HIBD6h后二者表达开始上升，24h上升更加明显，而假手术组各个时间点二者表达差异无统计学意义（P〉0．05）。与假手术组比较，HIBD组各时间点二者的表达均明显上升，差异有统计学意义（P〈0．01）。（3）缺氧缺血后各时间点磷酸化的PERK的表达和CHOP的表达呈正相关（r=0．997，P〈0．05）。结论脑缺氧缺血后，随着凋亡的出现，磷酸化的PERK和CHOP表达水平升高，提示PERK—CHOP通路的活化可能参与了新生大鼠HIBD神经细胞凋亡的发生。Objective To investigate the effect and mechanism of phosphorylated protein kinase R-like ER kinase（p-PERK） and C/EBP homologous protein （CHOP） after hypoxic-ischemic brain damage （HIBD）. Methods Neonatal 7-day-old Sprague Dawley rats were divided into sham-operation control group and HIBD group（ n = 30 per group）. Each group was divided into 0 h,6 h and 24 h subgroup after operation （n = 10 per group）. The ratio of apoptosis of brain cell was measured by flow cytometer and the expression of p-PERK and CHOP were detected by Western blot. Results （ 1 ） Apoptosis cell appeared at 6 h in HIBD group,the ratio of cell apoptosis was（2. 17 ±0. 19）%. The apoptosis cell obvious increased at 24 h,the ratio of cell apoptosis was（ 13.42 ±0. 83 ） %. There was a significant increase in the ratio of apoptosis after HIBD 6 h and 24 h, as compared with sham-operation control group E （ 0. 57±0. 06 ） % （ P 〈 0. 01 ） ]. （ 2 ） The expression of both p-PERK and CHOP was very low in sham-operation control group. In the HIBD group, the expression of both p-PERK and CHOP began to increase at 6 h and increased furthermore at HIBD 24 h. The differences in the expression levels of p-PERK and CHOP in HIBD group among different time points were significant（ P 〈 0. 01 ）. （3） The expression of p-PERK positively correlated with the expression of CHOP （ r = 0. 997,P 〈 0. 05 ）. Conclusion With the emerging of apoptosis after HIBD, the expression of both p-PERK and CHOP increases. The imbalance in the expression of PERK induces the apoptosis of brain cells in the H1BD of neonatal rats by regulation of CHOP expression.

关 键 词：缺氧缺血性脑损伤 新生大鼠 蛋白激酶R样内质网激酶 C/EBP同源蛋白 凋亡 

分 类 号：R722.1[医药卫生—儿科]