摘要
目的观察深低温对全脑缺血大鼠海马Bax表达的影响及其与细胞凋亡的关系，从而进一步探讨深低温的脑保护作用机制。方法30只Wistar大鼠在制备成体外循环全脑缺血模型后按随机数字表法分为3组：对照组（模型制备后5min立即处死取海马组织）、常温缺血组[于大鼠肛温（37．0±0．3）℃下停循环5min后立即处死取海马组织]和低温缺血组[热交换器配合体外冰屑诱导将大鼠肛温降至（18．0±0．5）℃，停循环5min后立即处死取海马组织1，每组10只。采用实时荧光定量PCR检测海马组织BoxmRNA表达，采用免疫组化染色检测Bax阳性细胞吸光度值，采用Westemblotting检测神经细胞胞浆细胞色素C（Cyt-C）蛋白表达，采用TUNEL法检测神经细胞凋亡情况。结果与对照组比较，常温缺血组海马BoxmRNA（2．734±0．301）、阳性细胞吸光度值（0．326±0．017）及神经细胞胞浆Cyt-C蛋白表达（4．14±0．79）以及神经细胞凋亡率[（53．95±4．23）％1均明显升高，差异均有统计学意义（P〈0．05）；而低温缺血组海马BaxmRNA（1．679±0．309）、阳性细胞吸光度值（0．209±0．019）及神经细胞胞浆Cyt-C蛋白表达（1．45±0．49）以及神经细胞凋亡率[（15．56±3．02）％]均较常温缺血组明显降低，差异均有统计学意义（P〈0．05）。结论深低温可通过抑制海马Bax表达而抑制神经细胞Cyt-C释放，阻止细胞凋亡，从而起到脑保护作用。
Objective To detect the effect of profound hypothermia on Bax expression and its relationship with cell apoptosis in the rat hippocampus after global ischemia. Methods Animal models of cardiopulmonary bypass （CPB） were established in 30 Wistar rats which were randomized into blank control group （rats were sacrificed 5 min after model making and hippocampus tissues were prepared）, normothermia ischemia group （circulatory arrest was performed at [37.0±0.3]℃ for 5 min, and then, rats were sacrificed 5 min after model making and hippocampus tissues were prepared） and hypothermia ischemia group （circulatory arrest was performed at [18.0±0.5]℃ by ice crumbles for 5 min, and then, rats were sacrificed 5 min after model making and hippocampus tissues were prepared, n=10）. Quantitative real-time PCR （qPCR） was used to detect the Box mRNA expression, immunohistochemical method was used to detect the Bax protein expression, Western blotting was used to detect the cytochrome C （Cyt-C） expression, and TUNEL was used to measure the cell apoptosis. Results The Box mRNA expression （2.734±0.301）, optical density of positive cells （0.326±0.017）, Cyt-C protein expression （4.14±0.79） and cell apoptosis rate （53.95% ±4.23% ） increased significantly in the normothermia ischemia group as compared with those in the blank control group （P〈0.05）. The Box mRNA expression （1.679±0.309）, optical density of positive cells （0.209±0.019）, Cyt-C protein expression （1.45±0.49） and cell apoptosis rate （15.56%±3.02%） in the hypothermia ischemia group decreased significantly as compared with those in the normothermia ischemia group （P〈0.05）.Conclusion By inhibiting the expression of Bax, profound hypothermia can inhibit release of Cyt-C into the cytoplasm and thus reduce cell apoptosis in the hippocampus after global ischemia in rats, which may be one important way that profound hypothermia has protective effect on brain tissue with ischemic injury.
出处
《中华神经医学杂志》
CSCD
北大核心
2017年第12期1286-1289,共4页
Chinese Journal of Neuromedicine
基金
江苏省青年医学人才项目（QNRC201684）
关键词
深低温
脑缺血
Bax
细胞色素C
细胞凋亡
Profound hypothermia
Cerebral ischemia
Bax
Cytochrome C
Cellapoptosis
