双下肢缺血预处理经神经通路对大鼠脑局部缺血再灌注损伤的保护作用

目的 研究双下肢缺血预处理对大鼠脑局部缺血再灌注损伤的保护作用并探讨其中神经通路的介导作用。方法 SD雄性大鼠随机分为 5组 (n=10):假手术组；大脑中动脉阻塞 （MCAO）组、远端缺血预处理 （RIPC）+MCAO组、股神经及坐骨神经切断 （FS）+RIPC+MCAO组、FS+MCAO组。将大鼠大脑中动脉阻断90 min形成大脑局部缺血，再灌注24 h后进行神经行为学缺损评分，计算脑梗死容积， 行HE染色评价组织形态学改变，TUNEL染色及Caspase-3染色检测细胞凋亡数。结果 再灌注 24 h后RIPC+MCAO组脑梗死容积 （18.24%）明显小于MCAO组 (30.92%)，TUNEL及Caspase-3染色凋亡细胞数量 (20.81，5.78)亦较MCAO组 (45.23，12.94)少,而FS+RIPC+MCAO组的梗死面积 （28.77%）与凋亡细胞数 (53，11.83)与MCAO组的差异无统计学意义；RIPC+MCAO组的神经行为学缺损评分和HE染色结果好于MCAO组，但于RIPC之前切断神经则与MCAO组的差异无统计学意义。结论 双下肢缺血预处理可对脑局部缺血再灌注损伤产生保护作用，且这种作用是通过神经通路介导的。

Protective Effect of Ischemia Preconditioning of Lower Limbs on Brain Ischemia-reperfusion Injury via

【Abstract】 Objective To explore if ischemia preconditioning of lower limbs could protect the local ischemia reperfusion damage in rat brain and the role of neural pathways during the process. Methods Fifty male Sprague-Dawley rats were randomly assigned into five groups (n=10 for each group). Group Ⅰ was sham group. Group Ⅱ was the occlusion of middle cerebral artery (MCAO) for 90 min. Group Ⅲ was remote ischemic preconditioning (RIPC) 24 h before MCAO. Group Ⅳ was femoral nerve and sciatic nerve (FS) resected before RIPC and MCAO. Group Ⅴ was FS resected only before MCAO. All the rats in the later four groups were subjected to brain reperfusion after MCAO for 90 min. The brain samples were harvested 24 h after MCAO for the evaluation of neuroligical deficit score (NDS) and infarct volume, histomorphlogical study with HE staining, as well as the evaluation of neuron apoptosis with TUNEL staining and Caspase-3 staining. Results The infarct volume in group RIPC+MCAO （18.24%） was smaller than that in MCAO group (30.92%), and TUNEL and Caspase-3 staining also demonstrated significantly lesser apoptotic neurons (20.81, 5.78) in comparison with MCAO group (45.23, 12.94). However, the infarct volume (28.77%) and apoptotic neurons (53, 11.83) of FS+ RIPC +MCAO group did not show statistical difference when compared with those of MCAO group. The results of NDS and HE staining in RIPC+MCAO group were better than those in MCAO group, while they showed no statistical difference in the condition of nerve resected before RIPC+MCAO when compared with MCAO group. Conclusion The ischemia preconditioning of lower limbs may provide protection on ischemia-reperfusion injury in rats brain through neural pathways.