U0126对蛛网膜下腔出血小鼠细胞外信号调节激酶途径的调节作用  

Regulating effects of U0126 on the extracellular signal regulated kinase pathway after subarachnoid hemorrhage in mice

作　　者：刘江[1] 李冉[1] 崔建忠 王凯杰 张宇新[1] 高俊玲[1] 

机构地区：[1]河北联合大学基础医学院,唐山063000 [2]工人医院神经外科,唐山063000

出　　处：《神经解剖学杂志》2012年第3期283-288,共6页Chinese Journal of Neuroanatomy

基　　金：河北省自然科学基金(C2009001247);卫生部人类疾病比较医学重点实验室开放课题(ZDS200801);河北省教育厅重点课题(ZH200803);河北省卫生厅医学科学研究重点计划指令项目(20110164)

摘　　要：目的:研究细胞外信号调节激酶(ERK)、天冬氨酸特异性半胱氨酸蛋白酶-8(caspase-8)在蛛网膜下腔出血(SAH)后早期脑损伤中的作用,并探讨ERK特异性抑制剂U0126通过此途径发挥作用的保护机制。方法:采用稳定的非开颅血管内穿线法制备小鼠SAH模型,并于术前30 min经尾静脉给予U0126(0.1 mg/kg),分别在术后12、24、48 h 3个时相点取右侧大脑动脉标本,HE染色观察大脑动脉的形态改变,并检测大脑中动脉(MCA)的直径变化;应用免疫印迹法检测各组p-ERK1/2、caspase-8蛋白表达,TUNEL法检测MCA内皮细胞凋亡。结果:模型组小鼠MCA出现严重血管痉挛,直径减小,p-ERK1/2、caspase-8蛋白均有不同程度增强,凋亡细胞增多。与模型组比较,治疗组小鼠各时相点上述3项指标的表达均呈不同程度下调,MCA管径增加,脑血管痉挛缓解。SAH 12～48 h时p-ERK1/2与caspase-8的表达呈正相关。结论:SAH后ERK表达增强可通过激活caspase-8信号途径诱导大脑动脉内皮细胞凋亡;U0126可减少大脑动脉内皮细胞凋亡,其机制之一可能是通过阻抑ERK通路活化实现的。Objective：To investigate the role of extracellular signal regulated kinase（ERK）,caspase-8 signaling pathway in early brain injury and the protection mechanism of U0126（ERK specific inhibitor） by above signal pathway after subarachnoid hemorrhage（SAH）.Methods： A stable and reliable mice SAH model was made by endovascular perforation without opening cranium,and the mice in U0126 group was treated with U0126（0.1 mg/kg） via tail vein before 30 min of operation.At different time points（12,24,48 h） after operation,the cerebral artery in right side was sampled,and HE staining was used to observe the morphological change of the cerebral artery and checked the diameter changes of the middle cerebral arteries（MCA）.Western Blot was used to examine the expression of p-ERK1/2 and caspase-8,and the apoptotic cell number was detected by TUNEL method.Results： SAH produced severe acute vasospasm in the MCA,and the diameters of MCA in SAH mice were smaller than those in the control mice.The expressional level of p-ERK1/2,caspase-8 and the number of apoptosis cells was significantly increased in SAH group.While the above detected marker was decreased in the U0126 group than those in the SAH group,the diameter of the MCA was increased and vasospasm was released.The expression of p-ERK1/2 was positively correlated with caspase-8 at 24-48 h of SAH.Conclusions： The increased expression of ERK in cerebral arteries may induce the apoptosis of endothelial cells by activation of caspase-8 signaling pathway after SAH.The U0126 can reduce apoptotic of cerebral arteries endothelial cells by inhibiting the activation of the ERK signaling pathway.

关 键 词：蛛网膜下腔出血 大脑中动脉 细胞外信号调节激酶 半胱氨酸天冬氨酸特异性蛋白酶-8 小鼠 

分 类 号：R743.35[医药卫生—神经病学与精神病学]