脑缺血再灌注后细胞色素C和卡配因基因表达对神经细胞凋亡的影响(英文)

Influence of cytochrome C and Calpain gene expressions on neuronal apoptosis after ischemia-reperfusion injury

背景:细胞凋亡与细胞色素C(cytochromeC,CytC)、卡配因、Bcl-2家族和半胱天冬酶家族等基因表达有密切关系。脑缺血再灌注过程中,下调卡配因的表达,抑制CytC的释放可减少细胞凋亡。目的:研究大鼠局灶性脑缺血再灌注后神经细胞凋亡及其与CytC和卡配因基因表达的关系。设计:随机对照的实验研究。地点和材料:实验地点:青岛大学医学院脑血管病研究所和山东省脑血管病防治重点实验室。动物:成年健康雌性SD大鼠36只,体质量230～270g,清洁级,由中国科学院上海实验动物中心提供。方法:全部实验均由所有作者完成。具体方法:应用线栓法建立SD大鼠大脑中动脉阻塞(middlecerebralarteryocclusion,MCAO)再灌注模型,应用TUNEL法观察脑缺血再灌注后神经细胞凋亡,原位杂交技术检测CytCmRNA和卡配因mRNA的表达。主要观察指标:凋亡细胞数;CytC和卡配因的阳性细胞数。结果:脑缺血再灌注后2h脑组织即出现凋亡细胞,在皮质区和纹状体区分别于1d和2d达高峰,此后逐渐减少。脑组织CytCmRNA和卡配因mRNA的表达自缺血再灌注后2h后逐渐增高,皮质区12h达高峰犤分别为(122.50±6.69)和(138.50±6.25)个/视野犦,纹状体区1d达高峰犤分别为(119.25±5.12)和(105.00±4.58)个/视野犦,以后逐渐下降。CytCmRNA和卡配因mRNA的表达与细胞凋亡的?

BACKGROUND:Programmed cell death has a close relationship with gene expression,such as cytochrome C(Cyt C),Calpain,Bcl 2 family and caspases.Down regulation of calpaine gene expression during ischemia reperfusional(IR) injury may inhibit Cyt C release,which results in attenuated cell apoptosis OBJECTIVE:To investigate the correlation of neuronal apoptosis with gene expressions of Cyt C and calpain in rats after focal cerebral IR injury. DESIGN:Randomized experimental case control study. SETTING and MATERIALS:The study was carried out at the Cerebrovascular Disease Research Institute of Qingdao Medical College and Cerebrovascular Disease Prevention Laboratory of Shandong Province.Thirty six healthy clean adult female SD rats,weighing 230-280 g, were provided by Shanghai Experimental Animal Center of Chinese Academy of Science. METHODS:Reperfusion animal models of middle cerebral artery occlusion(MCAO) were established on SD rat by thread bolt method.TUNNEL method was used to observe neuronal apoptosis after IR and in situ hybridization technique was applied to detect the expressions of Cyt C mRNA and Calpain mRNA. MAIN OUTCOME MEASURES:Numbers of apoptosis neurons and Cyt C and Calpain positive cells. RESULTS:Neuron apoptosis occured 2 hours after cerebral IR,increased to the peak 1 day and 2 days after IR in cortex and striatum,respectively,and then gradually decreased.Cerebral Cyt C mRNA and Calpain mRNA expressions increased 2 hours after IR,and to the peak at 12 hours in cortex[(122.50±6.69) and(138.50±6.25) eye field,respectively],and 1 day in striatum[(119.25±5.12) and(105.00±4.58) eye field,respectively],and then decreased gradually.The spacial expression of Cyt C mRNA and calpain mRNA were consistent with the region of neuronal apoptosis. CONCLUSION:Neurons in cortex were more vulnerable to ischemic injury than those in striatum.Cyt C and calpain gene expressions play a key role in inducing cell apoptosis.