异氟烷对兔脑缺血再灌注损伤的保护作用及机制研究

Study on the protective effect and mechanism of isoflurane on cerebral ischemia-reperfusion injury in rabbits

目的:通过研究异氟烷(ISO)预处理对兔脑缺血再灌注损伤的保护作用及机制,为临床治疗脑缺血提供实验依据。方法:取健康雄性兔45只随机分为5组:假手术组(Sham组)、缺血再灌注组(模型组)、1%ISO预处理10 min组(A组)、1.5%ISO预处理10 min组(B组)及2%ISO预处理10 min组(C组),每组各9只。线栓法制备脑缺血再灌注损伤模型,缺血2 h再灌注24 h后对其进行以下实验:(1)神经功能损害评估Zeal Longa5及NSS评分;(2)氯化三苯基四氮唑(TTC)染色检测脑梗死体积;(3)免疫组织化学检测测定脑内NF-κBP56蛋白的表达;(4)流式细胞术检测细胞凋亡数;(5)脑中脑皮质组织超氧化物歧化酶(SOD)活性的变化。结果:模型组Longa5评分、脑梗死体积、脑内NF-κBP56含量均大于其它组(P<0.05),C组各项指标低于其它两组,差异有统计学意义(P<0.05);A、B、C组脑中SOD活性均略低于Sham组,其中C组与Sham组最为接近,模型组脑中SOD活性明显低于A、B、C组与Sham组。Sham组细胞凋亡比例低于A、B、C组及模型组(P<0.05)。结论:异氟烷对兔脑缺血再灌注损伤有明显的保护作用,且在本研究中高剂量ISO作用效果最佳。

Objective:To investigate the protective effect and mechanism of isoflurane(ISO)preconditioning on cerebral ischemia reperfusion injury in rabbits,and to provide experimental evidence for the clinical treatment of cerebral ischemia.Methods:45 healthy male rabbits were randomly divided into 5 groups,9 rabbits in each group.They were divided into Sham group,ischemia-reperfusion group(I/R),1%ISO preconditioning group(group A),1.5%ISO preconditioning group(group B),and 2%ISO preconditioning group(group C).Thread embolism method was used to established cerebral ischemia-reperfusion injury model,and the following experiments were performed after 2h of ischemia and 24h of reperfusion:(1)Zeal Longa5 and NSS scores for neurological impairment assessment.(2)Triphenyltetrazolium chloride(TTC)staining test Cerebral infarction volume.(3)Immunohistochemical detection was used to determine the expression of NF-κB P56 protein in the brain.(4)Flow cytometry was used to detect the number of apoptosis.(5)The change of SOD activity in the middle cerebral cortex of the brain.Results:The Longa5 score,cerebral infarction area,and NF-κBP56 content in the brain of the group I/R were higher than those in other groups(P<0.05).The indicators in the pretreatment group C were lower than those in the other two groups,and there were statistical differences between the groups(P<0.05).SOD activity in the three pretreatment groups was slightly lower than that in the Sham group,of which group C was the closest to that in the Sham group,and SOD activity in the group I/R was significantly lower than that in the ISO group and Sham group.The proportion of apoptosis in Sham group was lower than that in ISO group and lower than that in I/R group,with statistical difference(P<0.05).Conclusion:Isoflurane has a significant protective effect on cerebral ischemia-reperfusion injury in rabbits,and its efficacy increases with concentration in a certain concentration range.