深低温停循环对大鼠大脑皮质HIF-1α和凋亡相关基因的影响  

Effect of whole body deep hypothermic circulatory arrest on expression of HIF-1α,Bcl-2 and Bax in cortex neurons of rats

作　　者：魏亮[1] 高永军[2] 杨成[1] 张燕飞[1] 孙志扬[1] 徐蔚[2] 

机构地区：[1]同济大学附属上海市东方医院神经外科,上海200120 [2]昆明医学院第二附属医院神经外科

出　　处：《山西医科大学学报》2011年第4期275-279,共5页Journal of Shanxi Medical University

基　　金：教育部科学技术研究重点项目(02141)

摘　　要：目的了解深低温停循环对大鼠大脑皮质缺氧诱导因子(HIF-1α)及凋亡相关基因的影响及其脑保护机制。方法将11只大鼠随机分为3组:深低温停循环组(DHCA,n=5)、常温停循环组(NTCA,n=3)和正常对照组(NC,n=3),对3组同时采用体外插管法建立大鼠闭胸式深低温停循环5 min缺氧模型,DHCA组低温条件下停循环5 min,NTCA组正常体温下停循环5 min,NC组建立体外循环后不进行降温和停循环。采用Real-time PCR方法测定HIF-1α、Bcl-2和Bax mRNA在大鼠大脑皮质中的表达。结果 HIF-1α在DHCA组和NTCA组表达较NC组明显增高(P<0.01),DHCA组较NTCA组表达增高(P<0.05)。Bcl-2在各组间差异无统计学意义(P>0.05);Bax在NTCA组中较NC和DHCA组表达增高(P<0.05)。结论缺氧可诱导HIF-1α和Bax的表达,深低温可诱导HIF-1α表达而抑制Bax的表达;深低温及缺氧对Bcl-2影响较小。深低温可能通过诱导HIF-1α同时抑制Bax的表达而达到脑保护作用。Objective To explore the effect of deep hypothermic circulatory arrest（DHCA） on expression of hypoxia-inducible factor 1α（HIF-1α）,B-cell leukemia/lymphoma-2（Bcl-2） and Bcl-2 associated X（Bax） mRNA in cortex neurons of rats.Methods Eleven SD rats were divided randomly into three groups：deep hypothermic circulatory arrest group（DHCA,n=5）,normal temperature circulatory arrest group（NTCA,n=3）and normal control group（NC,n=3）.The rat model of closed-chest DHCA was established by means of external cannulation.Circulatory arrest was performed for 5 min in rats at 18 ℃ in DHCA group and at normal body temperature in NTCA group,while no circulatory arrest and deep hypothermia in NC group.Then the cerebral cortexes were removed and dissociated.The mRNA expression of HIF-1α,Bcl-2 and Bax was measured in cortex neurons of rats by real-time PCR.Data were analyzed by software SPSS12.0.Results The levels of HIF-1α mRNA expression in DHCA group and NTCA group were significantly higher than in NC group（P〈0.01）.Compared with NTCA group,the level of HIF-1α mRNA expression in DHCA group increased（P〈0.05）.The level of Bax mRNA expression in NTCA group was higher than in NC group（P〈0.05） and DHCA group（P〈0.05）.The level of Bcl-2 mRNA expression showed no significant difference among 3 groups（P〉0.05）.Conclusion Ischemia can induce the expression of HIF-1α and Bax mRNA,and deep hypothermia could decrease the expression of Bax and induce the expression of HIF-1α,but have no significant effect on Bcl-2.Possibly,deep hypothermia may play a protective role by increasing the expression of HIF-1α and decreasing the expression of Bax.

关 键 词：深低温停循环 HIF-1Α BCL-2 BAX 大脑皮质 大鼠 

分 类 号：R364[医药卫生—病理学]