血管紧张素1-7对氧糖剥夺/复氧海马神经元的保护作用

血管紧张素1-7（angiotensin 1-7, Ang1-7）在神经系统中发挥重要作用。已有研究发现，Ang1-7在脑缺血动物模型中发挥保护作用，但至今未见有关Ang1-7对氧糖剥夺/复氧（oxygen-glucose deprivation/ reoxygenation, OGD/R）损伤神经元的保护作用及其机制的研究报道。本研究以厌氧培养及不含葡萄糖的EBSS培养基培养、建立新生大白鼠原代培养的海马神经元OGD/R模型模拟脑缺血环境，实验分为3组：正常对照组、实验对照组和Ang1-7处理组。倒置显微镜观察神经元形态显示，Ang1-7处理组的神经元形态明显改善|CCK8试剂盒检测发现，Ang1-7处理组的细胞活性提高|流式细胞术研究发现，Ang1-7处理组的神经元凋亡和坏死率降低、神经元内Ca2+及NO水平降低|Western印迹结果发现，Ang1-7处理组Bax表达降低，Bcl-2表达增加。以上结果说明，Ang1-7可降低OGD/R神经元中NO和Ca2+水平，降低Bax蛋白、增加Bcl-2蛋白的表达，减少OGD/R神经元凋亡和坏死率，对OGD/R神经元发挥了保护作用。本研究为进一步在神经元水平上研究Ang-1-7的保护机制奠定基础，对中风等脑缺血疾病的防治具有重要意义。

Angiotensin 1- 7 Protects against Oxygen-Glucose Deprivation/Reoxygenation-induced Injury of Primarily Cultured Hippocampal Neurons of Rats

Angiotensin 1-7 (Ang1-7) plays important roles in the nervous system. Previous studies found that Ang1-7 played a protective role in cerebral ischemia animal model. But the protection effect of Ang1-7 on hippocampal neuron injury induced by oxygen-glucose deprivation/reoxygenation and its mechanism had not been reported. In this study, the hippocampal neuron of new born SD rat was cultivated. Anaerobic incubator and EBSS medium were used to establish oxygen glucose deprivation/reoxygenation model of hippocampal neuron. The cells were divided into three groups: the normal control group, the experimental contro1 group and the Ang1-7 stimulation group. Inverted microscope was adopted to observe the morphology of hippocampal neurons. Compared with the experimental control group, the cell morphology in Ang1-7 group was greatly improved. The results of CCK8 assays showed that the neuron vitality in Ang1-7 group was greatly increased. Flow cytometry was adopted to study cell apoptosis and the levels of Ca2+ and NO in hippocampal neurons. The results showed that cell apoptosis and necrosis rate in Ang1-7 group were decreased. At the same time, the levels of Ca2+ and NO in Ang1-7 group were significantly decreased. Western blot showed that Bax expression was decreased and Bcl-2 expression was increased in Ang1-7 group. These results suggested that Ang1-7 played protective roles through increasing Bcl-2 expression, reducing the levels of Ca2+, NO and Bax, and reducing cell apoptosis and necrosis rate. The results in this study would lay the foundation for further research on the protection mechanism of Ang1-7 in neurons and the prevention and control of cerebral ischemia related diseases.