肢体远端缺血预处理对缺血性脑卒中保护作用的DWI研究  

MR DWI research on the inhibition of limb remote ischemic preconditioning toward stroke

作　　者：吴富淋[1] 陈秋雁[1] 缪绍维[1] 魏鼎泰[1] 

机构地区：[1]福建医科大学附属宁德市医院放射科,福州352100

出　　处：《功能与分子医学影像学（电子版）》2014年第4期17-22,共6页Functional and Molecular Medical Imaging(Electronic Edition)

基　　金：福建省医学创新基金(2009CX23)

摘　　要：目的探讨经肢体远端缺血预处理(LRP)后大鼠脑缺血模型的弥散加权成像(DWI)改变及其相关机制。方法 98只成年SD大鼠随机分为三组,LRP组、缺血对照组及假手术组。分别在恢复再灌后1 h、3 h、12 h及24 h行MRI检查采集T2WI/DWI图像;并结合神经学评分、TTC染色从行为学和形态学上进行辅助评价。Western blot检测和免疫荧光检测缺血组和LRP组各时间点,及假手术组AQP4、i NOS的表达情况,并通过共染进行定位。结果与另外两组比较LRP组行为学评分增加,大脑梗死面积减少,同时LRP组在DWI上出现的病灶亦较缺血对照组减小。连续性的DWI检测显示LRP组的病灶出现在恢复再灌后3 h,而缺血对照组多出现在1 h。Western blot表明AQP4和CGRP均在缺血后表达下降,而LRP组的AQP4表达水平则高于假手术组,并有随着时间的延长而上升的趋势。i NOS在缺血后的表达量较假手术组增多,而LRP组表达降低。AQP4主要表达在血管内皮细胞上及邻近血管周围的细胞膜上。结论 LRP减轻脑缺血引起的脑水肿很可能与上调AQP4的表达及抑制i NOS的表达相关。Objective To investigate the changes in DWI images ofrats that underwent limb remote ischemic preconditioning and investigate the possible mechanism. Method Adult SD male rats were subjected to limb remote ischemic preconditioning （LRP）, control ischemia and sham surgery, animals then underwent MR T2WI/DWI imaging 1 h, 3 h, 12 h, 24 h after restore reperfusion. After that neurological behavior evaluation and TTC staining were carried out. Western blot and immunofluorescence staining were used to investigate the expression of AQP4 and iNOS. Result Limb remote ischemic preconditioning improved the neurologic deficit score, Infarct size was reduced, the lesions on the DWI were also reduced compared to the control ischemia group. Such results were consistent with the result of MRI detection. Results of successional DWI detection showed the presence of lesion was prolonged by limb-preconditioning from 1 hour after in control ischemia to 3 hour. Western blot and immunostaining analysis showed that LRP accelerated protein expression of both AQP4 wich were decreased after stroke.In addition, LRP decreased iNOS expression after stoke. Conclusion Limb remote preconditioning performed in one limb may alleviate encephaledema leaded by ischemia by accelerating the expression of AQP4 and restricting the expression of iNOS.

关 键 词：肢体远端缺血预处理 脑卒中 水肿 水通道蛋白-4 诱导型一氧化氮合酶 DWI 

分 类 号：R743.3[医药卫生—神经病学与精神病学] R445.2[医药卫生—临床医学]