低氧预适应保护缺血脑组织效应中CaMKⅡ的作用机制

低氧预适应保护缺血脑组织效应中CaMKⅡ的作用机制

李海涛

首都医科大学燕京医学院病理生理教研室

收稿日期:2012-06-26 修回日期:2012-10-16 出版日期:2013-02-15 发布日期:2013-02-15
通讯作者: 李海涛

Increased Phosphorylation of CaMKⅡ in Penumbra Cerebral Tissues of HPC-MCAO Mice

LI Hai-Tao

Department of Physiology, Yanjing Medical College, Capital Medical University, Beijing 101300, China

Received:2012-06-26 Revised:2012-10-16 Published:2013-02-15 Online:2013-02-15
Contact: LI Hai-Tao

李海涛. 低氧预适应保护缺血脑组织效应中CaMKⅡ的作用机制[J]. .

LI Hai-Tao. Increased Phosphorylation of CaMKⅡ in Penumbra Cerebral Tissues of HPC-MCAO Mice[J]. .

摘要/Abstract

摘要：

【摘要】目的 探讨钙调蛋白依赖性蛋白激酶Ⅱ( CaMKⅡ)在低氧预适应(HPC)保护小鼠缺血脑组织中的作用。方法 36只健康雄性BALB/c小鼠随机分为常氧假手术组、HPC假手术组、常氧缺血组和HPC缺血组，每组6只应用 Western blot并结合Gel Doc凝胶成像系统定量检测4组小鼠脑组织内CaMKⅡ蛋白表达量和磷酸化水平的变化，用免疫组化检测常氧缺血组和HPC缺血组小鼠脑皮层CaMKⅡ磷酸化水平。结果与常氧假手术组相比，常氧缺血组小鼠皮层缺血核心区和半影区CaMKⅡ蛋白表达量和磷酸化水平均显著降低(P < 0.05)，HPC缺血组缺血半影区CaMKⅡ 磷酸化水平及p-CaMKⅡ阳性细胞数目高于常氧缺血组(P < 0.05)。结论 HPC减缓缺血半影区CaMKⅡ磷酸化水平的降低，可能参与减轻因中脑动脉闭塞所致小鼠缺血性脑损伤作用。

关键词: 脑低氧预适应, 脑中动脉梗塞, CaMKⅡ, 磷酸化水平, 蛋白表达量

Abstract:

[Abstract] Objective To investigate the effect of hypoxic preconditioning (HPC) on middle cerebral artery occlusion (MCAO)-induced brain injury in mice，and changes of calcium/calmodulin-dependent protein kinaseⅡ(CaMKⅡ) phosphorylation thereof. Methods Thirty-six healthy male BALB/c mice were randomly divided into 4 groups: the normoxic sham surgery (H0-sham) group, HPC-sham group, H0-ischemia group and HPC-ischemia group. Changes of CaMKⅡ phosphorylation in the brain of mice were detected by Western blot combined with Gel Doc imagine systems. Levels of CaMK Ⅱ phosphorylation in brain cortex of mice were detected by immunohistochemistry. Results Both phosphorylation and protein expression levels in the ischemic core and penumbra were significantly decreased in H0-ischemia group compared with those in H0-sham group (P < 0.05). But the phosphorylation levels of CaMKⅡ and the positive cell number of p - CaMK Ⅱin the penumbra were significantly higher in HPC-ischemia group than those of H0-ischemia group (P < 0.05). Conclusion The de? creased CaMKⅡ phosphorylation level in ischemia penumbra might involve in the attenuation of middle cerebral artery occlusion (MCAO)-induced brain injury in mice.

Key words: Cerebral hypoxic preconditioning, MCAO, CaMKⅡ, Phosphorylation, Protein expression