脑缺血再灌注后神经细胞凋亡和细胞色素C基因表达及肌苷的干预作用  

Effects of inosine on the apoptosis and the expression of cytochrome C mRNA in neurons after cerebral ischemia and reperfusion in rats

作　　者：张红[1] 王粤[1] 龚薇薇[1] 孙国岚[1] 郭云良[1] 

机构地区：[1]青岛大学医学院附属医院脑血管病研究所,266003

出　　处：《中华老年医学杂志》2004年第9期652-655,共4页Chinese Journal of Geriatrics

基　　金：山东省自然科学基金资助项目 (Y2 0 0 1C0 4)

摘　　要：目的　研究肌苷对大鼠局灶性脑缺血再灌注后神经细胞凋亡和细胞色素C(CytC)基因表达的影响 ,探讨肌苷的神经保护作用机制。　方法　应用线栓法建立SD大鼠大脑中动脉阻塞(MCAO)再灌注模型 ,腹腔注射肌苷注射液 (10 0mg/kg) ,原位末端标记 (TUNEL)和原位杂交技术分别观察神经细胞凋亡和CytCmRNA表达。　 结果　脑缺血再灌注后 2h皮质区与纹状体区即出现凋亡细胞并逐渐增加 ,皮质区和纹状体区分别于 1d和 2d达高峰 ,之后逐渐减少 ,至 14d接近于假手术组水平 ;经肌苷治疗后凋亡神经细胞减少 ,其中再灌注 12h～ 7d较对照组相应时间点减少明显 ,差异有显著性 (P >0 0 5 )。CytCmRNA于脑缺血再灌注 2h开始表达 ,皮质区 12h达高峰 ,纹状体区 1d达高峰 ,以后逐渐下降 ;肌苷治疗组CytCmRNA表达于再灌注 12h～ 7d在皮质区、12h～ 14d在纹状体区较对照组显著降低。　结论　脑缺血再灌注损伤可诱导CytC基因表达和神经细胞凋亡 ,肌苷可能通过对二者的抑制而发挥其神经保护作用。Objective To investigate the effects of inosine on the neuronal apoptosis and the expression of cytochrome C mRNA after focal cerebral ischemia and reperfusion in rats,and to explore the neuroprotective mechanisms of inosine. Methods SD rats model of focal ischemic reperfusion was induced by intraluminal middle cerebral artery occlusion (MCAO) with a nylon monofilament suture. Inosine (100 mg/kg) was injected intraperitoneally twice following MCAO. Apoptosis was determined by terminal deoxynucleotidy1 transferase-mediated uridine 5'-triphosphate-biotin nick end -labeling (TUNEL) staining. In situ hybridization was performed to examine the expression of cytochrome C mRNA. Results TUNEL-positive cells were observed 2 h after reperfusion and peaked at 1 d and 2 d after reperfusion in cortex and striatum respectively. Inosine reduced the number of TUNEL-positive cells at and after reperfusion 12 h. Cytochrome C mRNA expressed in cortex and striatum of ischemic hemisphere as early as at 2 h after reperfusion and reached a peak at 12 h and 1 d in cortex and striatum respectively. Inosine could diminish the expression of cytochrome C mRNA at and after reperfusion 12 h. Conclusions Inosine might play a neuroprotective role by inhibiting the neuronal apoptosis and the expression of cytochrome C mRNA which were induced by cerebral ischemia reperfusion injury.

关 键 词：肌苷 神经细胞凋亡 皮质区 纹状体 脑缺血再灌注 表达 C基因 细胞色素C RNA 凋亡细胞 

分 类 号：R743[医药卫生—神经病学与精神病学] R971.2[医药卫生—临床医学]