Abstract: Abstract: Objective To investigate the effects and underlying mechanisms of Apelin-13 injected by intarcerebroventricular on cerebral ischemia-reperfusion injury in middle cerebral artery occlusive (MCAO) rats． Method Focal cerebral ischemia in rats was established by 2 h occlusion of the middle cerebral artery and 24 h reperfusion． After 2h ischemia，Apelin-13 and NS were administrated intracerebroventricularly． The neurologic deficient scores were investigated according to Zea-Longa’s Standard． The infarct areas were assessed with software Imagepro Plus 6. 0 after TTC staining． The activities of inducible nitric oxide synthase ( iNOS) and glutathione peroxidase(GSH-PX)were determined by specific kit． And the levels of Bcl-2、Bax and Caspase-3 in central neutral system were measured by western blot． Result Apelin-13(1. 0 μg·kg － 1 ) could decrease the neurologic deficient score，reduce the infarct areas of the brain in CIRI rats，depressed the activity of iNOS，enhance the activity of GSH-PX，increase the expression of Bcl-2，and decrease the expression of Bax and Caspase-3． Conclusion Apelin-13 can protect the ischemia-reperfusion injury，the mechanism may be related to depressing the level of NO， getting rid of more ROS，adjusting the expression of apoptotic and anti-apoptotic proteins．

Key words: Apelin-13, cerebral ischemia-reperfusion injury, Bcl-2, Bax, Caspase-3, inducible nitric oxide synthase, glutathione peroxidase

摘要： 摘要: 目的 研究 Apelin-13 侧脑室注射对大鼠脑缺血再灌注损伤的保护作用及相关机制。方法 侧脑室埋管后， 采用线栓法制备大鼠大脑中动脉栓塞模型，脑缺血 2 h 后侧脑室注射给药。再灌注 24 h 后进行 Zea-Longa 神经功 能评分;TTC 染色法测定大鼠脑梗死面积;试剂盒测定大鼠脑组织内诱导型一氧化氮合酶( inducible nitric oxide synthase，iNOS)和谷胱甘肽过氧化物酶( glutathione peroxidase，GSH-PX) 的活性;Western blot 法测大鼠脑组织 Bcl-2、Bax 和 Caspase-3 三种蛋白的表达水平。结果 Apelin-13(1. 0 μg·kg － 1 )侧脑室给药能改善大脑的神经功能， 减少脑缺血面积，降低 iNOS 活性，增加 GSH-PX 活性，增加 Bcl-2 的表达，减少 Bax 和 Caspase-3 的表达。结论 Apelin-13 对缺血再灌注脑组织保护的可能机制包括降低 NO 水平，加强自由基清除，以及调节凋亡相关蛋白表达。

关键词: Apelin-13, 缺血再灌注损伤, Bcl-2 蛋白, Bax 蛋白, Caspase-3 蛋白, 诱导型一氧化氮合酶, 谷胱甘肽过氧化物酶