肢体缺血后处理对大鼠慢性脑缺血后脑内LINGO-1的表达及神经功能的变化

目的:观察大鼠肢体缺血后处理后脑内LINGO-1表达的变化,研究肢体缺血后处理改善慢性脑缺血后神经损伤的分子机制。方法:采用50%三氯化铁处理双侧颈总动脉的方法建立慢性脑缺血模型,随机将大鼠分为假手术组、模型组和肢体缺血后处理组。大鼠肢体缺血后处理3周后采用三等分Y型电迷宫方法观察各组大鼠的学习记忆能力,RT-qPCR检测LINGO-1的mRNA,Western blot法测定LINGO-1的蛋白水平。结果:与模型组相比,肢体缺血后处理组大鼠学习记忆能力显著增加(P0.05)。假手术组大鼠LINGO-1的mRNA及蛋白水平有少量阳性表达。肢体缺血后处理组大鼠LINGO-1的mRNA及蛋白水平均显著下降(P0.05)。结论:慢性脑缺血大鼠脑内LINGO-1水平明显上调,肢体缺血后处理可明显降低LINGO-1的表达水平,并提高学习记忆能力,这可能是肢体缺血后处理改善慢性脑缺血神经功能的分子机制之一。

Effects of limb ischemic postconditioning on expression of LINGO-1 in brain and neural function after focal cerebral infarction in rats

AIM: To observe the expression of LINGO-1 in the rat brain after ischemic stroke, and to explore the molecular mechanism of improving the neural damage after chronic cerebral ischemia by limb ischemic preconditioning (LIP). METHODS: The chronic cerebral ischemia model was established by the method of processing bilateral common carotid arteries with 50% FeCl₃. The rats were randomly divided into sham operation group, model group and LIP group. The study and memory abilities of the animals were observed by the test of Y-type labyrinth after treatment for 2 weeks, and the mRNA and protein expression of LINGO-1 was detected by RT-qPCR and Western blot. RESULTS: Compared with model group, the study and memory abilities were significantly increased (P<0.05). Only a small amount of positive expression of LINGO-1 at mRNA and protein levels in sham operation group was observed. The expression of LINGO-1 in model group was increased significantly. Compared with model group, the expression of LINGO-1 at mRNA and protein levels was significantly decreased in LIP group (P<0.05). CONCLUSION: LIP improves the study and memory abilities and reduces the expression level of LINGO-1. LINGO-1 may be one of the molecular targets for LIP improving the neural function of chronic cerebral ischemia.