摘要
目的探讨缺氧缺血性脑损伤(hypoxia ischemia brain damage,HIBD)时端粒酶逆转录酶(telomerase reverse transcriptase,TERT)的表达及神经元凋亡情况。方法42只清洁级7日龄SD大鼠,雌雄不限,体重12～18g,随机分为假手术组(6只)和缺氧缺血组(36只)。缺氧缺血组实验动物分离右侧颈总动脉,双线结扎,缝合皮下组织及皮肤,并低氧处理,制备HIBD动物模型;假手术组仅将缝线从右侧颈总动脉下穿过,不结扎,缝合切口,不作低氧处理。分别于术后4、8、12、24、48及72h处死大鼠取脑组织,采用免疫组织化学法检测TERT和CC3蛋白表达,采用TUNEL染色检测细胞凋亡。结果缺氧缺血组TERT蛋白表达于术后4h开始增加,24～48h达高峰,之后略有下降;CC3蛋白表达于术后4h开始增加,24h明显升高,48h及72h维持较高水平。假手术组TERT和CC3仅有少量弱阳性表达。缺氧缺血组术后各时间点TERT及CC3蛋白表达与假手术组比较,差异均有统计学意义(P<0.05)。TUNEL染色显示,缺氧缺血组术后4～8h神经细胞凋亡开始增多,24～48h达高峰,72h仍维持在较高水平;假手术组偶见阳性细胞。缺氧缺血组术后各时间点阳性细胞计数与假手术组比较,差异均有统计学意义(P<0.05)。结论缺氧缺血能诱导脑组织中TERT表达增加,TERT可能对神经细胞凋亡起一定保护作用。
Objective To investigate the expression of telomerase reverse transcriptase （TERT） and cell apoptosis in neonatal rats with hypoxia ischemia brain damage （HIBD）. Methods A total of 42 7-day-old SD rats （12-18 g,male or female） were randomly allocated into sham-operation group （n=6） and hypoxia-ischemia （HI） group （n=36）. In HI group,the rats were anesthetized with ethylether. The right common carotid artery （CCA） was exposed and permanently ligated with a 7-0 silk suture through a midline cervical incision. A duration of 2.5 hours of hypoxia （8%O2 / 92%N2） was used to produce HIBD model. For sham-operation group,the CCA was exposed without ligation or hypoxia. The brain tissues were harvested at 4,8,12,24,48,and 72 hours after completion of an HI insult. The expressions of TERT and CC3 were detected by immunohistochemical staining. The apoptosis cells were detected with TUNEL staining method. Results The expression of TERT was increased at 4 hours after HI injury,significantly increased at 24-48 hours and then decreased at 72 hours. The expression of CC3 was increased at 4 hours after HI injury,significantly increased at 24 hours and still maintained high expression at 48 hours and 72 hours. However,in the sham-operation group,both the expressions of TERT and CC3 were extremely low. The expression of TERT and CC3 were higher in the HI group than in the sham-operation group at different time points,and the differences were signifi cant （P 〈0.05）. The TUNEL staining showed that the positive cells in hippocampus and cortical areas were increased at 4 hours after HI injury,significantly increased at 24-48 hours and maintained a high level at 72 hours. However,there was few positive cells in the sham-operation group. There were signifi cant differences between the HI group and the sham-operation group at different time points （P 〈0.05）. Conclusion TERT could be induced by HI in neonatal rats,and might have a protective role in regulating the cell apoptosis in the neonatal HI
出处
《中国修复重建外科杂志》
CAS
CSCD
北大核心
2010年第5期588-593,共6页
Chinese Journal of Reparative and Reconstructive Surgery
基金
国家自然科学基金资助项目(30825039
30973236)
四川省科技厅基金资助项目(8ZQ026-069)~~
关键词
缺氧缺血性脑损伤
细胞凋亡
端粒酶逆转录酶
大鼠
Hypoxia ischemia brain damage Apoptosis Telomerase reverse transcriptase Rat
