线栓法复制昆明小鼠局灶性脑缺血再灌注模型的稳定性研究

Stability of cerebral focal ischemia/reperfusion model induced by monofilament in Kunming mice

目的:探讨影响线栓法复制小鼠局灶性脑缺血再灌注模型稳定性的因素。方法:60只雄性昆明小鼠按体重分为3组:A组(18-21 g)、B组(22-28 g)和C组(30-35 g)。线栓栓塞法制备大脑中动脉缺血再灌注模型。模型评价指标包括:PRM2激光多普勒脑血流仪检测大脑中动脉供血区的血流,按Longa标准进行小鼠运动行为评分,TTC染色法测量小鼠脑梗死灶体积,ELISA法检测脑皮层丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性。结果:与C组相比,A、B两组模型成功率高(P<0.05),尤以B组模型成功率更高;A组死亡率显著高于B组和C组(P<0.05);A、B两组行为学评分显著高于C组(P<0.05),表现出明显的神经功能障碍;A、B两组小鼠脑梗死灶的体积显著高于C组(P<0.05),表现出明显的脑损伤,损伤侧脑皮层中MDA含量明显升高,SOD活性明显下降。结论:小鼠体重与线栓直径良好匹配、进线深度和24℃左右的室温是保证造模成功的3个重要因素。脑组织脂质过氧化反应可作为脑缺血再灌注损伤的有效指标。

AIM： To study the stability of mouse cerebral ischemia/reperfusion model induced by the method of monofilament.METHODS： Sixty male Kunming mice were divided into 3 groups according to the body weight： group A（18-21 g）,group B（22-28 g） and group C（30-35 g）.Ischemia/reperfusion（I/R） model was made by middle cerebral artery occlusion（MCAO） with nylon monofilament.To evaluate the mouse MCAO model,the method of PRM2 laser Doppler was used to detect the cerebral blood flow,the neurological deficit scores were determined by Longa standard and infarction volume was detected with TTC staining.The content of malondialdehyde（MDA） and activity of superoxide dismutase（SOD） were also measured by ELISA.RESULTS： The successful rates of model establishment in both group A and group B were higher than that in group C（P0.05）,especially the highest in group B.The mortality in group A was significantly higher than that in group B and group C（P0.05）.The behavior scores and cerebral infarct volume in group A and group B were significantly higher than those in group C（P0.05）.Obvious brain injury and neurological deficits were also observed in group A and group B with the higher content of MDA and the lower activity of SOD in the cerebral cortex of the injury side.CONCLUSION： There are three important factors to ensure the success and stability of MCAO mouse model induced by monofilament,i.e.the diameter of monofilament matching the body weight of the mice,the suitable length of monofilament within the blood vessel,as well as the maintaining of proper room temperature during experiment.The MDA content and SOD activity are also effective indexes for evaluating the cerebral I/R injury.