肌苷对大鼠脑缺血再灌注损伤后神经细胞巢蛋白表达的影响

背景肌苷参与机体多方面的代谢过程并对缺血性脑损伤有一定的保护作用,但其机制尚需做进一步研究.目的研究大鼠缺血性脑损伤后巢蛋白(Nestin)基因表达的变化规律,探讨肌苷治疗中枢神经缺血性损伤的作用机制.设计随机对照的基础研究.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完成.实验材料成年健康雌性SD大鼠68只,以线栓法建立大脑中动脉缺血再灌注模型.随机分为治疗组和对照组,每组再随机分为缺血1.5 h再灌注2,6,12,24 h,2,3,7,14 d组(n=4),另外4只作假手术组.干预所有治疗均由作者亲自操作.治疗组大鼠于缺血1.5 h再灌注前给予空腹注射肌苷注射液100 mg/kg,2次/d.对照组大鼠同步注射相同剂量的生理盐水.所有大鼠置于同样的空间笼养.主要观察指标应用原位杂交技术检测脑缺血再灌注后脑组织NestinmRNA的表达.结果对照组缺血侧NestinmRNA表达皮质除2h以外、纹状体除2,6 h以外、室旁区除2,6 h,14 d以外各时间点均明显高于假手术组.治疗组NesfinmRNA表达较对照组于2,6 h,7,14d在皮质,14 d在纹状体有所降低,3 d在皮质、纹状体及室旁区均显著升高,7 d仅在纹状体、室旁区显著升高.结论肌苷可以促进大鼠脑缺血再灌注后Nestin mRNA的表达,从而达到神经组织结构和功能恢复的目的.

Effect of inosine on the expression of neuron neuroepithelial stem protein in rats after cerebral ischemic reperfusion injury

BACKGROUND: Inosine takes part in various metabolism of body and plays a certain role in protecting ischemic brain from injury, but its mechanism still requires further study. OBJECTIVE: To study the expression principles of neuroepithelial stem protein(Nestin) in rats after ischemic injury and to explore the therapeutic mechanism of inosine on ischemic injury of central nervous system.DESIGN: Randomly controlled basic study. SETTING and MATERIALS: Setting: This experiment was performed in the Institute of Cerebrovascular Diseases, Medical College of Qingdao Universify and the Key Laboratory of Cerebrovascular Diseases of Shandong Province. Materials: Sixty-eight healthy adult female SD rats were used to establish ischemic reperfusion animal model by middle cerebral artery occlusion with a nylon monofilament suture. Rats were randomly divided into treatment group and control group, and each group was redivided randomly into 2,6,12,24 hours,2,3,7,14 days groups after 1.5-hour ischemia ( n = 4). The other 4 rats served as sham-operation group. INTERVENTIONS: The whole experiment was carried out by the authors.Rats in the treatment group were injected with inosine(100 mg/kg body mass) peritoneally twice a day before reperfusion of 1.5-hour ischemia, while those in the control group were injected with the same dosage of saline at the same time. All the rats were breeding in the equal place of cages.MAIN OUTCOME MEASURES: In situ hybridization was used to examine the expression of Nastin mRNA in brain tissue of the rats after cerebral ischemic reperfusion. RESULTS: The expression of Nestin mRNA in cortex, striatum and extraventricular zone increased significantly in ischemic hemisphere of the control group except that of reperfusion 2 hours in cortex, 2 and 6 hours in striatum, 2, 6 hours and 14 days in extraventricular zone. The expression of Nestin mRNA in the treatment group decreased in cortex 2, 6 hours, 7, 14 days after reperfusion and in striatum 14 days as compared with that of the control group, then increased significantly in cortex, striatum and extraventricular zone 3 days after reperfusion, but increased only in striatum and extraventricular zone at 7 days. CONCLUSION: Inosine can promote the expression of Nestin mRNA in rats after cerebral ischemic repeffusion and thereby enhance the rehabilitation of the structure and function of nervous tissue.