缺氧缺血性脑损伤新生大鼠脑组织细胞红蛋白的表达

Expression of cytoglobin in brain tissues of neonatal rats with hypoxic-ischemic brain damage

目的探讨细胞红蛋白（cytoglobin，CYGB）在7日龄新生大鼠缺氧缺血性脑损伤（hypoxic-ischemic brain damage，HIBD）脑内的表达变化。方法健康7日龄SD大鼠70只，按简单随机抽样法随机取50只制备HIBD模型作为HIBD组，再随机分为HIBD后0、4、12、24和48h组，每组10只；假手术组10只，只分离左颈总动脉，不结扎，也不放入缺氧箱；另10只不做任何处理作为对照组。假手术组术后即断头取脑，对照组同时取脑，HIBD组在相应时间点取脑。采用免疫组织化学法和Western印迹法从蛋白水平分析CYGB在脑组织中的分布及表达特点。结果（1）免疫组织化学染色显示CYGB主要表达于大脑皮质、丘脑和海马神经元的胞浆，HIBD组CYGB表达数量及染色强度均高于对照组，其中缺氧24、48h组表达最强。（2）Western印迹结果显示，HIBD后0、4、12、24和48hCYGB平均吸光度分别为261．5±5．0，263．0±5．4，464．3±6．8，522．8±11．2，512．9±7．9，明显高于假手术组（117．6±7．0）及对照组（116．6±9．0），P〈0．01。其中缺氧0和4h组明显高于对照组（P〈0．01）；缺氧12h组的表达明显高于缺氧0、4h组（P〈0．01）；缺氧24、48h组明显高于缺氧12h组（P〈0．01）；缺氧0、4h组间，缺氧24、48h组间差异无统计学意义（P〉0．05）。结论7日龄新生大鼠HIBD后脑内CYGB表达明显增强，并且随着缺氧缺血发展呈现时相性变化，提示其可能在脑缺氧缺血的适应性调节过程中起重要作用。

Objective To study the expression of eytoglobin （CYGB） in the brain tissues of 7-day-old rats with hypoxic-isehemie brain damage （HIBD）. Methods Seventy 7-day-old SD rats were divided into HIBD group（n = 50）, sham-operated group （n = 10） and control group （n= 10）. HIBD group rats were HIBD models and subdivided into 0 h,4 h,12 h,24 h and 48 h groups after hypoxie-ischemic injury. Brain tissues of rats in sham-operated and control group were collected after operation immediately and brain tissues in HIBD group were collected at different times. Western blot and immunohistoehemistry were used to detect the expression of CYGB. Results test showed that CYGB was located in the cortex, thalamencephalon and hippocamp and stronger CYGB expression was found in the HIBD group in comparison with the other two groups. Western blot showed that the expression of CYGB at 0 h,4 h, 12 h, 24 h and 48 h after hypoxic-isehemie injury （261.5±5.0,263.0±5.4,464. 3±6. 8,522. 8±11.2,512. 9±7. 9） were significantly stronger than that in the sham-operated group （117.6±7. 0） and the control group （116.6±9. 0）（P〈0. 01）. The expression of CYGB was up-regulated in HIBD 12 h group than in HIBD 0 and 4 h groups, and that in HIBD 24 and 48 h groups was higher than in the HIBD 12 h group. However, no significant difference were found between HIBD 0 and 4 h groups, neither between the 24 and 48 h groups （P〉0. 05）. Conclusions CYGB may have important role in protecting the brain from hypoxic-ischemie injury.